The death of zero carbon

Since their somewhat surprising election win in May, the Tory government has been getting stuck into some of its bete noirs, or should that be bete verts. They have taken the axe to feed-in-tariffs, to solar farms and on-shore wind, to the Green Deal, to the 2016 zero carbon targets and to any uprating of Part L, the energy efficiency regulations.

Their all too brief explanation is that they consider green subsidies to be too great a burden on consumers and tax payers and that it is good for business and the economy if they are reduced or abandoned altogether. Whilst they are too smart to go on record as saying that climate change is not important, and they are making very supportive noises about the forthcoming Paris Climate Convention, their actions speak otherwise.

For whilst all these green subsidies have their faults, and their critics (I count myself as one), they are all about promoting change in the way we supply and use energy. They are not being improved or refined: they are, bit by bit, being dumped and they are not being replaced. Just about the only coherent energy policy being promoted by the Tories is that we should all get behind fracking.

There are lots of problems with fracking, not least that the people in the shires seem to have even less appetite for it that they do windfarms. Yet the Tories have pandered to the anti-windfarm brigade by withdrawing support for onshore windfarms (the most cost-effective renewable technology), whilst showing no such considerations for similar folk who oppose fracking.

This tells us that the current moves are clearly ideological. The subsidies required to kick start a clean energy revolution are peanuts compared to other areas of government spending and in withdrawing them the government is clearly saying these things don't matter. Their actions would do the Republican Tea Party or Tony Abbott's Australian Liberal government proud. Stick it to the Greens!

So how did we get here? How come the British Conservative response is so different to other European countries, notably Germany which also has a conservative-led administration but one which could hardly have a more different climate policy in place? And what of the Climate Change Act of 2008 which sets out the UK's carbon budgets? Will that soon be repealed?

I've longed nursed a suspicion that the Treasury is a hot bed of sceptics and that Osborne is happy to play along with them. His father-in-law, Lord Howell, is a noted fracking supporter and doesn't appear to like the push for renewables. What do they talk about at the dinner table? And with noted Tory supporters like Lord Lawson, Matt Ridley and the proprietors of the Telegraph, Mail and Times all champing at the bit to dismantle the green subsidies, it was perhaps inevitable that the plug would be pulled.

The Conservative manifesto makes interesting reading here.  It promised to "cut emissions as cost effectively as possible" and not to "support additional and distorting expensive power sector targets." I think "cost-effectively" used here is a smoke-screen for "get fracking" and the "power sector targets" are those set out in the Climate Change Act.

What still appears strange to me is that the whole issue of climate change has become so politicised and that the Right should have come down so strongly against action. There's nothing particularly left or right about environmental protection - it's surely something most civilised countries would wish for. No one is campaigning to re-introduce lead in petrol or asbestos, or for scrapping the Clean Air Act. Admittedly, environmental action is expensive, but then so are pensions and health care and education. What is a state for but to serve our best interests and can it really be in our best interests to do nothing about climate change, to leave it to chance?

The Right questions that the evidence that climate change is dangerous. Whilst this is possible, it is just as likely that the effects will be rather worse than mainstream science predicts. We simply don't know what we are doing to the climate and how it will behave as a result of our using it as a waste dump. But rather than address the issue, the Conservatives seem happy to do nothing at all, hoping that economic growth will sort matters out before too long — for which there is no evidence at all. British climate change policies have never been particularly coherent or logical, but at least we have had some. No longer. It seems we might just as well have elected UKIP as far as climate change policies are concerned.

Where have all our targets gone?

The Code for Sustainable Homes has come in for a lot of stick over the years. This blog hasn't spared the boot. But one thing the Code did achieve, when it was first introduced in 2007, was to make us aware of targets. The Code is split into six levels, each one being more demanding than the preceding one below. And, coupled with this, was a ratcheted timetable which suggested that we would all move up, level by level, until we reached Level 6 in 2016. Level 6 was the fabled state of Zero Carbon.

Now it was pretty clear from the start that Zero Carbon was never going to be much more than an aspirational target because it was so damned difficult to build. To get Level 6, a house had to supply all its own energy needs without recourse to fossil fuel. That meant it had to be loaded to the gunnels with PV on the roof and often this wasn't enough. There were many sites where it simply wouldn't have been possible to build a Level 6 house as it was originally envisaged. Only a politician could have dreamed this up.

So almost as soon as the Level 6 Zero Carbon target was conceived, moves started to water it down. First the definition changed to exclude certain forms of energy usage. Then allowable solutions were conceived to make it possible to offset some of the energy production. Then cunningly the actual definition of what zero carbon really meant was postponed indefinitely and eventually it became a mythical non-target, shunted into the long grass.

All along there has been this tension between energy saving and low-carbon energy production. They are quite different beasts and yet many of these eco-targets such as the Code conflated the two, so that you could save less energy if you produced more renewable power. Some saw this as a neat trade-off, others as a cop out.

And then along came Passivhaus which became fashionable in the UK after the Code was set up in 2007. Passivhaus is a target that concentrates solely on energy saving, and eschewed any additional green bling required to make a low energy house a zero carbon one. Most of the leading lights in this debate came to see the sense in separating energy consumption from energy production and the whole drive towards the Level 6, zero carbon target started to come off the rails.

It hasn't been helped by having a Tory party which has undergone a painful recasting of its green credentials and now seems to believe that energy targets and environmental regulations are not business-friendly or are, to turn a phrase, just expensive green crap.

So as we approach 2016, what has happened to our targets? If the Code is to be abandoned, and Passivhaus is still a long way from becoming mainstream, do we have any other environmental building targets to aim for? Well there are other candidates: Rory Bergin gives a good summary here of what he calls the rating tools. And there is good old Part L of the English building regulations which is neither a target nor a rating tool, but a standard which everyone has to adhere to. That's just been upgraded a little and is starting to look a bit more like a Passivhaus-verylite standard. But even Part L has become a political battleground now and it's not clear if it will ever be toughed-up again, or parked as another piece of green crap.

Scotland sings to a different hymnsheet. The Code has never been applied here and instead they have more measured reports, usually chaired by the esteemed Lynne Sullivan. She first did one in 2007 and it was a breath of fresh air compared to what was happening in England at the time. Recently, she has been called in to chair an update and it manages to cover all bases without committing to a target anytime soon.

But the issues don't go away. Should we be saddling new homes with renewable energy at all? Should we allow offsetting or allowable solutions? Shouldn't we be concentrating on building better homes instead? Should we be trying to close the performance gap between how a house is designed and how it is actually built? What about all the other environmental factors — water, drainage, ecology, materials? How much should these be targeted or legislated for? Should we have targets at all, or just basic ground rules also known as building regulations.

The short answer is that we don't know and the arguments go round and round the same circles with advocates of every avenue pushing home their own viewpoints. Against such a background, it becomes increasingly difficult to set targets as there is no longer any general agreement about what they should be.

In the meantime, Europe is coming up with a directive which requires each member state to have a  nearly zero-energy building standard in place by 2020. The working definition of this is that the nearly zero or very low amount of energy required should be covered "to a very significant extent" by energy from renewable resources. But it is up to member states to define what these terms mean.

In other words, it's not so very different from the Code for Sustainable Homes, only it's unlikely to set such a demanding target as zero carbon. The clue is in the title: nearly zero-energy. That can be as tough or as easy as you like.

Target culture is all very well as long as the target is far into the future or costs very little to achieve. But the demise of the Code — it's not yet decided but it now seems likely that it will disappear soon — shows that when the targets get too tough, it's our resolve that weakens. This mirrors the process which has gone on behind the scenes at the various climate summits that have tried to update Kyoto. Targets are fine as long as they only apply to others, or are far out into the future.

On Grid Parity

Robert Wilson (@CountCarbon), in a comment on my last blog, raises the issue of grid parity, asking what it is in reality. It's a good question. In essence, the idea is very simple. It's when new forms of energy production cease to be expensive and cost the same as existing methods. The idea being when solar PV, or wind turbines, or whatever tickles your fancy, costs the same as gas or coal burning then, voila, everyone will switch to the renewables. They will have achieved grid parity - that means that the electricity they supply to the national grid costs the same.

But I don't think Robert was looking for the mundane answer. He's a bit of an expert in these matters — I think he will know full well what grid parity means in theory. What he is driving at is that the concept is a whole lot more complicated to understand than my simple explanation makes out. And it is. Take a look at my last blog post for starters — this post more or less carries on from there so it's not such a bad idea to read that one first in any event.

There I make the point that comparing fossil fuel burning with renewables (or nukes — I'm fond of nukes) is an apples and oranges scenario. Fossil fuel has to be paid for but the plant to burn it in is cheap to build. All the others are almost free to run but the capital costs of getting the kit up and running are high. So, given this, the concept of grid parity is immediately challenged because to get a true cost of the electricity produced you have to perform a series of calculations involving a number of assumptions.

For instance, how long will the low-carbon plant last? If it's 25 years, the cost of the power will be x; if it's 50 years, it will be half as much (or x/2). We don't really know how long this plant will last because we have only just started rolling it out in large quantities, so immediately we are in the world of guesswork.

Suppose we decide on a 25-year lifespan, so that we can then work out a cost per unit of energy. We then have to look at 25 years of fossil fuel burning to make a comparison. But what will the cost of fossil fuel be in 25 years, not to mention all points in between? We'll need to know that in order to make a grand total so that we can compare with our low-carbon plant costs. But who knows what will happen to fossil fuel prices over 25 years. More guesswork.

This is an exercise you can do and, indeed, it's been done already many times, notably using DECC's 2050 pathways calculator. This suggests that a low-carbon route is likely to be no more expensive than a fossil fuel, business-as-usual one. But it does all depend on the assumptions being made.

If this really is the case, and that DECC's calculator has got it right, then we have already achieved grid parity and we simply don't need any green subsidies to kick start the low-carbon energy drive. Apparently financial logic dictates that we should move towards low-carbon electricity right away because it's already as cheap and is likely to get cheaper over time (fracking notwithstanding).

But no one really believes this to be the case. Institutions are not falling over themselves to build offshore windfarms or new nuclear power stations, or anything else that vaguely fits the bill. They all want generous subsidies or guarantees to take away the risk that the assumptions made might be wrong.

In other words, there is an apparent lack of will here. It easy to carry on with the business-as-usual scenarios because they are perceived as being less risky, because there is less money at stake. The low-carbon plant would have to become a whole lot cheaper than it is now for the institutions to take the plunge and invest in expensive low-carbon plant without any subsidy involved.

Or to put it another way, grid parity is not enough. We need to get to something like half-the-grid price before new energy forms will start to take over off their own bat. Or maybe even less. Once again, we are speculating.

Even then it's not quite so simple, because we need to sort out the power storage issues before we get too far down this track. Before we can talk about one-for-one substitution, we have to have adequate methods in place to store energy from intermittent renewables, otherwise we will still be building new gas plants well past 2050. Power storage has to be built into the financial equation. Without it, each unit of renewable electricity is worth ever so slightly less than the one produced immediately before it. This isn't a problem with nukes but then again nukes have their own problems.

It's not as if the business-as-usual route is without risks. Even discounting the effects of climate change over the next 35 years, this route ties us into burning fossil fuels and who knows how easy these will be to obtain, especially if the emerging economies continue to expand on the back of fossil fuel derived energy. It may be that fracking and other technological breakthroughs will bring about an unexpected energy abundance. But equally it may not. There's really no more logic to the pro-frackers position than there is to the EnergieWende route, as espoused by the anti-nuclear, pro-renewable Germans. Except, of course, that the German route does at least address carbon emissions, something the frackers only pretend to do.

Which brings us back to the concept of grid parity. It's not really measurable, certainly not in terms of unit costs of electricity. Instead, think of it as a ravine that has to be jumped. As you travel along the side of it, the gap gets steadily narrower but at what point do you actually decide to jump? Wherever that is would be where grid parity is. We could hang out a signpost that says Welcome to Grid Parity. But we won't know where to place it until we get there. And there's no guarantee that we ever will.

More Expensive Than What?

We keep hearing that low-carbon energy is more expensive. It's a pretty consistent meme pedalled by the right-wing media on both sides of the Atlantic. The further right the media, the more ruinous the expense. The left wing media tells a very different story, insisting that low-carbon energy is an investment with a long term payback.

But there is a little point here that's often overlooked by both sides. Fossil fuel burning is all about building cheap power stations and then buying in the fuel at whatever the market price may be, whereas the low-carbon alternatives are all about upfront capital costs, followed by almost-free running costs. (I'm excluding biomass here - it's much more like a fossil fuel in this respect).

So immediately you have a problem in that you are comparing apples and oranges. There's no easy way to tell which energy source is more expensive because you don't know what the future holds. To do that, you would need to know the price of fossil fuels many years ahead - like 25 or 50 years ahead. Only then would you be able to calculate which method had been more expensive. In effect, would the cost of fossil fuel burning be greater or less than the cost of financing the building of the low-carbon plant.

Now problems like this are not unusual. Businesses face them all the time. Consider a timber frame company thinking about investing £1 million in a fancy cutting machine which could automate the production line and reduce manpower costs by £250k a year. Even after factoring in a finance charge for the machine, it seems to make financial sense to spend the money. The business will reduce its costs and thus be more competitive, which should bring in more work and the production people who would lose their jobs in the joinery shop may be found new roles in the expanded business.

But the decision is not without risks. For instance, the amount of business being done might collapse and the projected savings of £250k per annum might not materialise. On the other hand, without the cutting machine, the prices charged by the business might become uncompetitive and the business could go into decline. Only with hindsight can you tell whether the decision to invest in a cutting machine is a good one. The question facing the directors is "Is it worth spending the extra money on this machine?" not "Which option is the most expensive?"

It's not so very different with our energy choices. We are not in a position to answer the more expensive question - there is simply no way of knowing until the capital investments we make now have run their course. As it stands, the capital markets are too timid to take the plunge and invest without some guarantee that they will see a return. Their fear is that the future price of energy will still be set by the availability of fossil fuels (and not mitigated by a carbon tax) and that if the price of fossil fuels falls below their financing costs, then they will have to bear a loss on every unit of energy they sell. Whereas the price of fossil fuels can rise and fall in response to supply and demand, the cost of finance is fixed at the outset, and fixed for a very long time.

Hence all the subsidies which governments are using to kickstart low-carbon energy production. The subsidies are not there because low-carbon energy "is more expensive", but because investors don't want to take a punt on fossil fuel costs many years ahead. Hence the need to socialise the decision, or for governments to shoulder the risk.

The trap which the government has fallen into is taking the green subsidy money from utility providers. If low-carbon energy is seen as a social good — which it is — then the money to get it off the ground should come from general taxation, where it would be lost in the mire, along with spending on healthcare, education and my bete noir HS2. Instead we have it pegged to our utility bills and there it's bound to become more and more unpopular as the Mail and the Telegraph continue to highlight just how much of our bills is going on subsidies.

My RHI response (don't get too excited)

The Renewable Heat Incentive Consultation closes today. Thanks to Kate de Selincourt who alerted me to this. I spent 40 minutes replying to some of the many questions and thought I would share my responses with blog readers. If you want to put your five pence worth in, be quick. It's here: RHI Consultation


1. What are your views about the proposed approach of a universally available tariff scheme? Is a tariff scheme the most efficient way to drive down technology costs, increase innovation and value for money, together with developing a homegrown supply chain? Please include reasoning for your response.

No, I think a tariff scheme, especially a deemed tariff scheme is not the way to go here. It seems to be modelled on FITs which have themselves been copied from Germany. FITs have been successful because they have been generous, but an installation-based subsidy has the potential to be just as successful and would be easier to comprehend from the consumer's standpoint and to administer for government agencies.

2. Do you think that there would be advantages in phasing or piloting roll out of the scheme? On what basis do you think it might make sense to phase or pilot the scheme?

Not really. FITS have been around long enough for us to know what is likely to happen. RHI has already been delayed. "Phasing" sounds like a polite way of adding further delay.

3. Do you think that there may be alternative or additional approaches to incentivising renewable heat deployment that we should pursue? What approaches do you think might add most value?

Yes. If there is to be any subsidy, it should be towards the installation costs. As with almost all non-fossil fuelled power sources, the running costs are generally much lower. It's the capital costs which are the barrier to uptake. Consequently, it makes little sense to incentivise the running costs, which is what the RHI is planning to do. The entry barriers remain just as large as ever, and only the rich or well connected will be able to take advantage of the RHI. This makes it regressive.

10. Do you agree with the proposed eligible technologies set out above? Are there others that should be considered for inclusion?

No, I don't. I am critical of the inclusion of biomass for reasons already made known to DECC. It is quite wrong-headed of us to be subsidising the burning of carbon-intensive fuels, and biomass is carbon-intensive. The inclusion of biomass in the RHI seems to be all about meeting 2020 EU targets for renewable usage, but that doesn't stop it being bad science.

If we must subsidise here, let's encourage the use of timber and other biomass materials in construction, where the carbon will be locked up for the critical years ahead when we have to reduce CO2 emissions.

11. Do you agree that an approved suppliers scheme is the best option for domestic biomass heat installations to demonstrate their use of sustainable fuel? Please provide reasoning with your response.

Hard to answer as I don't agree that biomass is a sustainable fuel. I guess some sort of auditing on the supply side is preferable to none at all, but I fear if biomass really takes off as a fuel source, that it will be sourced from further and further afield and that the auditing is likely to be compromised.

12. Do you agree that as part of the approved biomass supplier list we should assume a level of boiler efficiency?

Yes, if biomass is to be burnt, then at least control the boiler efficiencies. Insist on condensing biomass boilers at the very least.

23. What is the risk of switchback after the period over which tariff payments are made? Do you think this applies solely to biomass?

If you provide a mechanism for people to harvest a subsidy for their fuel bills, then of course there is a risk they will find another way of providing heating after the subsidy is withdrawn. That is yet another reason why capital cost subsidy is preferable.

39. Do you agree that deeming, as opposed to metering, is the most appropriate approach on which to base the calculation of RHI payments? If not, why not?

I can see why deeming is the preferred method, but I don't like it. It seems to highlight yet another problem with subsidising running costs, and not installation costs.

At last: a Passiv Wood Stove

In the rarified world of Passivhaus design there has been a small problem gnawing away at many enthusiasts, especially the selfbuilders. Wood stoves. They may not need them, but they want them. Focal point fires. Comfort. Neolithic TV. Call it what you will, but fires have a certain pull. And a pellet boiler just won't do.

There are — or have been — a couple of problems. One is that you need so little heat in a Passivhaus that the smallest wood stove is still too big. It's hard to make a wood stove that doesn't emit at least 4kW of heat, because that's what a log gives off when it's burning well and it seems a bit pointless to start burning kindling. That's not too big an issue — after all, as Passivhaus devotees keep saying, you can always open a window to make the room a bit cooler if you get too hot. Or you can start using the stove to heat hot water — but maybe not, as here things start to get a little bit more complex.

The next issue is the fresh air supply. Opening that same window is not really an acceptable failsafe option. And you can't fall back on the traditional, permanently open, ventilation grill — not when you've gone to so much trouble to make the place so airtight in the first place. In a draughty old pile, it's not really a problem because there is plenty of fresh air coming at you from all corners, but in a Passivhaus that's not the case. The supply air problem is usually addressed via an air duct piped directly into the stove. It's still not ideal, as it creates a cold bridge with the outside and another potential air leakage path — remember, all penetrations are bad news. But it's sort of on the right lines. It makes the stove room-sealed.

But another niggly little issue concerns spillage, the term given to the cloud of smoke emitted from the stove every time you open the door to re-load. In a draughty old pile, it quickly gets lost in the background, but in a Passivhaus the smoke will hang around until it's drawn away into the MVHR system, where it will end up clogging up the filter.

Well, as it happens, Chesney's, the wood stove manufacturers based in London, have just come up with a spillage-free stove design. Nigel True, their stove wizard, (pictured)

has been beavering away in his Whitstable workshop and has hit on a spillage-free design. "Until now, the best solution on the market has been a stove with a hinged door with an automatic closer," he told me. "We've come up with a design which diverts the air intake when the door opens so that the supply flow is redirected from an opening under the door into the stove, and away up the flue. It doesn't smoke at all"

The idea for a Passiv stove came about when they were contacted by CenterParcs with a view to supplying stoves in all their Passivhaus-standard chalets at their yet-to-be constructed Woburn site. The contract itself came to nothing, as CenterParcs later lowered their spec on cost grounds, but Chesney's carried on with the project and have now launched the resultant stove commercially. Its been through rigorous testing at Gastec in Cheltenham (the place where all UK good wood stoves get tested for smoke emissions) and has emerged with distinction. Both carbon monoxide and carbon dioxide emissions were rated as "negligible" even when subjected to worse case scenarios — i.e. forgetting to close the door.

At present, the new design has been fitted into a fairly basic 4.6kW Milan stove. It's being marketed under the name of Milan Passiv and the retail cost will be around £1150 plus VAT, which is around 25% more than the regular Milan stove. This puts it down at the lower end of what people pay for new wood burners.

As it happens, Passivhaus stove enthusiasts may have another promising development on the horizon. Poujoulat, the French chimney and flue manufacturers, are about to launch a triple-walled stainless steel flue which will work in conjunction with Chesneys new stove range. The advantage of a triple-walled flue is that the external cavity becomes the the stove intake air supply, in a the way a balanced flue works on a gas boiler. Not only does the intake air get pre-heated as it's drawn down the flue (thus increasing combustion efficiency), but the extra vent hole for supply air is eliminated. Instead of two penetrations, you have one: music to the ears of Passivhaus builders.

As of now, I don't think this product is yet on the market, but according to James Parkin, their UK technical manager, it's coming soon and anyone interested should contact him at j.parkin@poujoulat.co.uk

Coming to Terms with the N word

N is for nuclear.

Press that button and it changes everything. You enter a possible age of abundance and everything you have previously held dear becomes vaguely pointless. I suddenly feel myself turning a very pale green indeed, a milky eau-de-nil at best. And I wonder whether the main gist of what I have been writing about for the past twenty years has any relevance anymore.

It all comes down to risk. Is radiation more or less dangerous than carbon dioxide? It's all about dosage. Neither seems to be remotely harmful at low levels. At high levels, both are deadly. So it comes down to the lesser of two evils and, for me, the evidence is that it is better to risk radiation poisoning. And Fukushima has simply reinforced that view: it was nasty but and as yet no one has died. If that's the worst that can happen, then it's an acceptable risk, especially when set against the alternative.

I realise I am treading in the footsteps of many other dissident thinkers (Brand, Monbiot, Lynas are the obvious ones, and there are many more) and I'm certainly not feeling remotely original in all this. But as yet, no one seems to have really thought through the consequences of embracing a nuclear future. Because if you can live with one new nuke, you can live with 20, and maybe even 200.

And at that level, you can produce potentially all the energy we in the UK could ever dream of consuming and still leave enough to heat every house, office, school, hospital and swimming pool in the country all year long with the windows wide open. And surplus electricity could be used to manufacture fuels to power our cars and planes. And all of it without adding any CO2 to the atmosphere. And no messing about with carbon capture and storage, geo engineering, forests of wind turbines or seas of PV.

We could have a Jetson's lifestyle for a cost of around £600 per household per annum for the next 40 years. That would be enough to construct 5 nukes a year at around £4 billion per unit, which is what this overbudget one in Finland is costing. It would also create around half a million jobs. Compare that to the Green Deal! And if £600 sounds like a lot, remember that the power itself is very cheap to produce as about 98% of the cost of a new reactor is down to safety features, so £600 would end up being your annual fuel bill which is a lot less than you pay now (I bet). This is a technology that we have now at a cost we can afford.

You see, it changes everything.

And you can begin to see that darker greens than me will not like this option. Not because nuclear power is an unacceptable risk — funnily enough, no one says that about nuclear medicine which is the backbone of every cancer department in the world — but because it renders the whole world of sustainability and low carbon living pointless. In fact it plays into the hands of those right-wing tossers who have been throwing abuse at us for years for being closet socialists. You know, the ones who celebrated "Climategate." Maybe they have a point? Maybe we've all been posturing in a self-important way?

We may even be able to readily solve the CO2 problem without nuclear. I saw an interesting talk this afternoon from MIT Professor Dan Nocera about artificial photosynthesis which, he reckons, is much the most efficient way to store energy — beats batteries and pumped storage by an order of magnitude. He reckons that it may soon be commercially viable on a very small scale and that it could be powered by domestic solar cells, solving the old conundrum about not having energy when the sun isn't shining. Tata Steel have already licenced the research with a view to rolling it out in India.

OK, it's much greener, in the trad sense, than nuclear power, but the issue is that if it solves the problem easily, then we could still be facing an age of low carbon energy abundance. That's unsettling. Very.

Half FIT

One morning two weeks ago, I was awoken by some banging coming from a neighbour's roof. Draw back curtains and, lo and behold, across the street, some guys are up on the roof, seating some PV panels. Now this is a street running North-South, which means the panels are facing due east, so the amount of power they will create will be well down on their designed output.

To me, this was a sure fire sign that the Feed-in-Tariffs (FITS) had gone too far. Harvesting sunlight to make electricity in this manner is never really going to make much sense in a northerly latitude like ours, and doing it inefficiently like this really offends me. No way would anyone ever conceive of erecting east-facing PV if it wasn't for the promise of a big fat subsidy cheque. I've never liked these subsidies (having bleated about them on this blog often enough) and I don't have a huge amount of sympathy for these businesses which have apparently been "caught out" by this week's announcement that the subsidy is to be approximately halved forthwith (actually from December 12th).

Building a business plan on the whims of government renewable subsidies has never been a clever idea, especially in the UK which has a lamentable history in this area. We had Clear Skies, launched in 2003: they cocked that up. We had the Low Carbon Buildings Programme, launched in 2006: they cocked that up. Now the FITs, launched way back in April 2010, show every sign of being cocked-up too. Roll on the Renewable Heat Incentive!

Unintended consequences No 12: PV for water heating

One of the more bizarre aspects of the Feed-in-Tariff is that electricity producing photovoltaics are being used to power immersion heaters for hot water tanks. The "correct" technology for this task is the solar thermal panel, as these are much more efficient in converting sunlight into hot water. They are cheaper to install and they do it directly - or more directly than PV will ever do.

• 1m2 of solar thermal panel will produce around 500kWh of hot water per annum. Installation cost around £1500.

• 1m2 of solar PV will produce around 100kWh of electricity per annum. Installation cost around £700.

• Put another way, hot water powered by solar thermal is around half the price of hot water powered by PV.

Yet such is the distorting effect of the feed-in-tarrifs that people are now thinking of using PV for domestic hot water heating because they can't think of anything else to do with the surplus electricity produced on sunny days. Around 90% of the tariff is available just for producing electricity, and its easy to end up with a system that is oversized for purpose when the weather is right. On hot sunny days, you just don't need much in the way of electricity, so heating a hot water tank makes sense. And if you install more than 15m2 of PV on your roof, then you should be producing enough power to heat your domestic hot water, at least on a par with 3m2 of solar thermal.

So perversely, the way the feed-in-tariff is set up, one of the losers is set to be the solar thermal industry.



It makes senseBut only in terms of the strange Alice-in-Wonderland economics of feed-in-tariffs

Polysolar

Cambridge is known throughout Europe as Start-Up Alley. All these whacky, sometimes nerdy boys coming through with their PHDs in things mere mortals can barely comprehend are encouraged to commercialise their research and to form companies with Greek-sounding names to market their work. Mostly this sort of thing goes on in the quiet of a science park, of which there are a number dotted around the town, but every now and then you come face to face with one and this Saturday, Hamish Stuart of Polysolar was displaying his invention at the French Fair on Parker's Piece, close to the main shopping streets.

Now, if I got it correctly, Polysolar is a new type of photovoltaic panel which is formed by etching the power-generating circuits into a sheet of glass, and then sandwiching it between two more sheets. Compared with the crystalline PV panels which dominate the industry, its dead simple and therefore potentially very cheap. It produces less power than conventional PV but it has the potential to be used as a roofing material or as a facade. Building Integrated PV, or BIPV. There's a new acronym for you.

They have already completed several installations in Taiwan and China, but they now have sorted MCS accreditation and are ready to hit the UK, as it's all eligible for the feed-in tariff.

And I only went there to get a baguette for breakfast.

What if we face an energy glut?

Something I have blogged about before but seems all the more pressing since taking part in the 2050 Pathway debate, and playing with Prof David Mackay's 2050 calculator. Far from having to batten everything down to prepare for a world of extremely expensive low-carbon energy and possibly limited supplies, what if we end up with a glut of the stuff?

Press the nuclear option Button 4 on the calculator and it's immediately apparent that we are producing far more energy than we need without insulating a single house or fitting a single heat pump anywhere. OK, it's electrical energy and there are dozens of applications (mostly transport) which would struggle to cope with electricity as a fuel right now, but if we could gradually shift most of this across to electricity by 2050, we'd be home and dry. Well, not quite. I can't somehow see electric planes taking off, but just about everything else can be run on either electricity or fuel cells. Which require bucket loads of hydrogen, which is energy intensive to split from various compounds, but in a world of energy gluts, we have no problem using excess electricity to manufacture hydrogen.

But nuclear power? It's not sexy, is it? It's very expensive to build nuclear plants (but is it any more expensive than any of the other options?). And there are problems with nuclear proliferation and nuclear waste. And with uranium supplies. I know all that. But are these problems insurmountable? How about using thorium as a fuel instead? There's lot's of it and it's difficult to use it for nuclear weapons.

What's clear to me now is that it's going to be extremely difficult to reduce carbon emissions without using nuclear, even if it's only a partial solution. It involves getting lots of newish technologies to interact with one another and also involves managing intermittent supplies. Technically, it's all possible but it's not without huge risks too.

The problem of signing up to the nuclear Button 4 option is (for a housing blog) that it makes an awful lot of the demand-reduction stuff (which is my meat and drink) redundant. No more worrying about insulation and airtightness, nor about heat pumps or biomass or district heating. We could just plug electric boilers in everywhere and be done with.

It all seems extremely inelegant. But maybe it is the future? In a world where we are all mentally preparing to live the Good Life, the Jetsons will triumph after all.

More on the biomass debate

My last post resulted in the following email:

Mark,

I came across your blog this morning. I’ve seen a few discussions lately about the “greenness” of wood burning and I have a question of sorts you might be able to shed a little light on.

If I developed a mechanical widget that pulled CO2 out of the atmosphere and reacted it with some black magic producing useable energy and returning the CO2 a brief instant later to the atmosphere at the same rate it was removed a brief instant earlier, no doubt I’d qualify for all sorts of subsidies, praises and accolades.

So why is it, when I do the same thing over a slightly longer period of time, it’s suddenly as bad or worse than sending equivalent tonnages of carbon that’s been sequestered for a few tens or hundreds of million years into the atmosphere? On that time scale, burning even 100 year old wood is a very short carbon cycle.

Burning a 100 year old chunk of wood is simply putting back the carbon that was in the atmosphere 100 years ago, not increasing the total on a geological time scale and doing so prevents adding some amount of fossil carbon to the total in circulation.

We can’t, but if we could live entirely off burning wood, growing new wood at the same rate we consumed old wood and not release another atom of fossil carbon into the atmosphere, the natural sequestration of carbon would ensure that atmospheric carbon levels would decline very quickly, wouldn’t it?

So why all the fuss over burning wood?

Just curious.

Thanks,

Rick Gresham
Portland, OR

The nice thing about this letter is that you can immediately see the good points of the pro-biomass burning argument. Burning biomass is just fine because it doesn't add a whit to atmospheric CO2. Surely it can be at least part of the solution? You might just as well draw energy from the destruction of wood as let it rot naturally? All good points.

But the counter points are just a little stronger.

• The finite globe. There isn't and never will be anything like enough biomass available to burn to keep 6-10 billion people warm and happy. It will be a struggle to keep everyone fed. So why encourage burning it? It's not the solution.

• OK, you can't eat trees. But it's a two stage process. The first bit - the growing of it - is good news for atmospheric CO2; the second bit - the burning - is bad news. On balance they cancel each other out, but how much better it would be if we could encourage the first bit and delay the second bit. If the gap between growing and burning could be extended from 100 years to 200 years, then we are giving the atmosphere an extra 100 year breathing space at a time it could surely do with it. Therefore, it follows that if we should subsidise anything, it should be the use of biomass as a building material, thus extending the capacity of biomass to lock up carbon for longer than would happen naturally.

• There is a British-centric argument going on here which may not translate in woody Oregon. We have a proposal on the table to introduce a subsidy for burning biomass, the first of its kind in the world, to be known as the Renewable Heat Incentive. It's controversial, as you can imagine. So the argument here isn't just whether it's good or bad to burn biomass, but whether it's a good idea to give money to people to get them burning it.

• Rick's widget would be something new. It would be a miracle. It would change everything. In contrast, timber and biomass resources are things we are already blessed with. They do act like this miraculous widget, but only if everything that is burned is subsequently replaced. In other words, only if the resource is sustainably managed. That bit is critical. In fact, it's key. If we subsidise the burning of biomass, we risk upsetting this balance. People will hunt out biomass to burn without any guarantee that what they harvest will be replaced. And the more the craze for biomass grows, the bigger this pressure will become.

• We are not talking about a few wood burning stoves here. They are not the problem. It's the industrialisation of the process which threatens everything. If you start switching coal-burning power plants over to biomass (and it's already happening), then this supposedly huge untapped resource is very rapidly going to be coming under pressure. The more pressure on the resource, the less likelihood it will be managed sustainably. Just ask the fishermen.

Renewable Heat Incentive: the chaos continues

I have already blogged extensively about the Renwable Heat Incentive (the RHI), and the problematic nature of this proposed subsidy for heat pumps, biomass boilers and hot water solar panels. It was launched back in February 2010 as a “consultation document” but, in truth, it was rather more than this because it gave details not only of the projected subsidies available but also of a timetable. It stated that it would come into effect in April 2011 and that anyone installing renewable heat equipment after July 2009 would qualify for the incentive. That sounds like a a detailed proposal to me. The document called for responses by April. That deadline has long since passed and there has been no word since then about what will happen next.

A change of government in May hasn’t helped, particularly as spending cuts now seem to be the order of the day. Potential customers are all delaying orders until the position of the RHI becomes clear. Manufacturers and installers are now having to lay off staff because the market has dried up because of the confusion. All that is needed is some guidance from central government to relieve the situation.

So yesterday, Chris Huhne, the Energy Secretary, gets up in parliament and delivers his first annual energy statement. Everyone connected to this small industry is holding their breath for news of the RHI. And this is what he says. “In the heating sector, I can confirm our strong commitment to action on renewable heat. The Government is considering responses to the Renewable Heat Incentive consultation and will set out detailed options following the Spending Review.”

Groans all round. That could mean anything. It certainly doesn’t sound like anything soonish. My guess is that we now won’t see any response to the RHI Consultation until sometime in 2011. By which time this small industry will be a whole lot smaller.

What I learned at the BBA

Yesterday, I made good a promise to visit the BBA where I was the guest of Alan Thomas, the Sales & Communications Director, a stalwart of 25 years standing and, for many, the public face of the BBA.

The BBA is the largest and most important of our Third Party Accreditation bodies. It began life in 1966 (as the Agrément Board), a time when a lot of new (mostly plastic) materials were appearing in the construction industry and there was a perceived need to establish which of them were fit for purpose. It changed name to the British Board of Agrément in 1982 and today employs around 140 people, based at the same site near Watford that plays host to the BRE.

What did I learn?

• Relations between the BRE and the BBA have never been as close as was originally envisaged when they came to share the same site. They got distinctly frosty a few years back when the BRE bought WIMLAS, Wimpey’s accreditation body, and began offering a rival service. But recently, the BRE have chosen to pull out of this market and to concentrate on other things, so perhaps a thaw can take place.

• One of the things that Alan was keen to talk about was the Microgeneration Certification Scheme (MCS) which underpins the Feed-in-Tariffs and the Renewable Heat Incentive. It’s being run by Gemserv and, by all accounts, it’s becoming a bit of a rubber-stamping exercise, as there is so much kit out there that it is simply impossible to test it all thoroughly.

Hence the BBA sees a gap in the market for manufacturers and installers wanting to differentiate their products from the rest, by offering the additional security of BBA approval. The BBA have a team of inspectors out there who take the trouble to visit the Chinese factories where much of the PV is coming from and their aim is to sort the wheat from the chaff. Alan said to me: “We’ve been testing some of the PV systems coming into the UK and finding that there are issues: for instance, flashings that won’t last five years. We found one that can actually catch fire.”

• As well as microgeneration kit, they are currently testing dozens of new insulation materials. The BBA are one of only two places in the UK with a guarded hot box (the other is the National Physical Laboratory) and they are able to test the U value claims of various materials using it. Here is Alan Thomas pictured outside one of the BBA hot boxes. But U values are but one aspect of the tests. For instance, sheep’s wool has to be tested to see if it’s insect repellent and whether it reacts with metal fasteners which it might come into contact with.

• There seems to be a marked reluctance for window manufacturers to use the hot box testing to evaluate thermal performance. Most windows coming onto the market today in the UK publish performance U values which are therefore untested. Contrast this with Germany and Austria where testing is far more common. “There are 8 hot boxes in Vienna alone,” I was told. Sounds like a great opening line for a new Katie Melua song.

• Harmonised European testing remains as far away as ever. I must admit I quickly got lost in the alphabet-soup of CE markings, EOTA and ETA and BS EN nos. In theory, we should be getting pan-European standards, but in practice it seems that the member states have a long way to go to agree on this and it only applies to a very few areas so far.

• Which brings us onto another issue, Technical Barriers to Trade. Or to put it another way, is all this testing and certification there to protect consumers, or to create expensive obstacles for foreign competitors? This came to the fore recently when the revision to Part G of the building regs was held up for several months because a number of cylinder makers felt that the safety requirements being introduced were in excess of anything called for elsewhere in the EC, and the government was challenged in the European courts over this. Our govt won the day and now we have some very restrictive safety requirements for our cylinders (look at G3).

To be fair to the BBA, it’s an argument that they can’t win, as every safety inspection ever made could be said to be a “restraint of trade” by someone or other. All they can do is to carry on testing as well as they can, and hope that both manufacturers and consumers value their acumen.

• I asked Alan if the BBA had ever been successfully sued. His brow furrowed a little and he sucked his teeth and thought about it, and then replied thus: “It’s not a question I’ve been asked before but I think I can honestly say that we haven’t.” I must admit to being rather impressed at this point. He added that they didn’t exactly want to crow about it because to do so would be to invite some litigious sole to take them on, but even so it does rather suggest that they may be quite good at what they claim to be doing.

• And the BBA is not short of customers. They currently certify something like 1300 products and charge anywhere from £10k to £50k for approvals, which take anywhere from 3 months to 15 months to research and test. A BBA Certificate provides a route to market for manufacturers which might otherwise prove difficult: a building inspector or an insurance company will happily play ball with a BBA-approved product or system, whereas they may baulk at allowing something new and untested. Which is exactly what the idea was in the first place, back in 1966 when it all started.

• What’s just as interesting is that many companies succeed with new products without getting BBA approval (or any other 3rd party accreditation). There is no compulsion to get innovative products certified so it becomes a purely commercial decision for them. They have to weigh up whether the widely recognised acceptability of a BBA certificate is worth the time and expense. Some very well known names do: others don’t. Subject for further investigation, methinks.

• I asked at what point do products become so accepted that they no longer require certification. There is no hard and fast answer to this but Alan pointed out that, back in the 60s, timber frame was seen as so new that many manufacturers sought accreditation. Today, it’s become generally accepted. We discussed whether the same might happen with SIPS: Alan thought it might, but not yet, as the systems available all appear to be subtly different. He also suggested that many SIPS manufacturers were investigating whether to switch away from OSB to using Magnesium Oxide boards instead.

• The multifoil debate still bubbles away in the background. There is no doubt that TRADA’s approval of Actis, back in 1997 (was it really that long ago?) remains controversial and damaging to the whole certification business because it involved a very public falling out over how products should be assessed. The BBA has sided with the hot-box theorists (aka the BR 443 establishment viewpoint) and won’t approve multifoils for use on their own – though it accepts an increasing number to be used in conjunction with more conventional insulation products, and there was plenty of evidence of multifoils going through the testing processes at their labs.

• You can search for current BBA certificates here.

On the Renewable Heat Incentive

If ever an idea was half-baked, it's the Renewable Heat Incentive. On Feb 26, I was at a briefing in London, given by the civil servants who have designed the scheme, and the more I heard, the more worried I became. "It's a world first in policy terms" we were told, "we are truly in uncharted territory and we need your help." Hmmm. The nice gent from the Country Landowners Association was beside himself with thanks to the men from the ministry. Need I say more?

The most revealing conversation that I had took place during the lunchbreak when the man from British Gas talked to me about the funding of this scheme. It's big. By 2020, if it goes ahead as designed, it will add something like 35% to everyone's gas bills, as it seems that's where the levy to pay for it all will be drawn from. It's designed to pay for as many as 1.7 million subsidised renewable heat installations by then, at which point it's going to be paying out over £2 billion a year.

Make no bones about it, this is a carbon tax, but one being introduced by stealth, as it will creep into our fuel bills without it ever appearing as an additional item. I don't have any objections to a carbon tax — quite the opposite — but I would like the money raised to be used wisely, and the RHI really doesn't tick that particular box.

Why not?

Put very simply, it's subsidising the wrong people to put in the wrong kit.

As it stands there are a number of iniquities in the RHI, which I think will prove to be irreconcilable with logic or fairness.

• Arbitrary barriers between competing technologies. The technologies supported are biomass, heat pumps and solar thermal. Anything to do with fossil fuel is unacceptable. This however hides a very inconvenient fact that electricity is itself mostly derived from fossil fuels, and that unless your heat pump is set up really well, there is every chance that you will end up burning more fossil fuel (indirectly) if you switch from oil or gas to an electric heat pump. And the biomass offering is inconsistent. It seems some forms of biomass burning will receive a subsidy whilst others will not. Most clearly shown over the distinction between wood stoves, wood stove-boilers and pellet boilers. And whether or not they can (or should) have back-up boiler systems in place. As it stands, it looks like pellet boilers are IN but wood stove-boilers are OUT. It's not as if pellet boilers are fundamentally better than wood stoves with backboilers: many people can incorporate wood stoves in the homes, but have nowhere to put a pellet boiler (which needs utility space, and lots of it - QED you have to be wealthy to have a pellet boiler - it's not just a question of cost, it's also having the space).

• Deeming. Unlike the equipment being installed under the Feed-in-Tariffs (the output of which can all be metered), you can't meter the output from home heating appliances. So you calculate what it might be (using SAP, a home energy estimator). But deeming is really nothing different to a capital grant spread out over a number of payments. The crucial link between performance and reward, which is a key feature of Feed-in-Tariffs is broken. Therefore mediocrity is rewarded the same as excellence.

• The supported technologies are rewarded on a financial basis. The more expensive an installation, the more money gets thrown at it. Whether or not it actually saves any carbon, or even saves any money to the end user, is not part of the calculation. So if it's IN, its paid for at full market rate plus a calculated return of 12% (though only 6% for solar panels - a distinction I remain puzzled by). If it's OUT, then no money is available.

• Thus it stops dead any innovation in technologies that lie outside the grant-aided scheme. It also stops innovation involving a more complex interaction of techniques - cf heat recovery ventilation that incorporates an air source heat pump.

• It's not at all clear why biomass should receive a subsidy. Is it truly a renewable fuel? It pumps just as much CO2 into the atmosphere as gas. It's only renewable in the sense that we can grow more of it, which we can't with gas. If biomass is to receive a subsidy, it should be for delaying the point in the cycle where it gets burned, not for burning it. Plus biomass boilers are only ever going to be available to a very small minority of people (who just happen to have large houses!).

• Switching from fossil fuel to electricity for home heating. Again, it's none too clear that this is a wise move. Until the grid becomes much greener, the net result of the RHI may well be to push up carbon emissions. With large question marks hanging over the future of electricity production in this country, and whether we will have an infrastructure that can cope with the current demand in a few years time, why are we loading yet further demand onto the system?

• Which leaves solar thermal. The one technology here which is truly renewable. But it only gets a subsidy worth half as much as heat pumps and biomass, despite it being much cheaper to install, and despite it being open to a far wider section of the population. A strange decision if ever!

• It all points to a failure on the part of central government to introduce a clear and structured carbon tax on fossil fuel consumption, which is the logical way to approach this problem. OK, I know the reason for this: it is said to be politically impossible, and no other country has tried to do it either, and now the electorate don't believe in global warming in any event. All good points. But if you don't address it, then you end up with half-baked incentives like this, which are dressed up to look progressive but end up being very expensive to administer and yet they don't begin to tackle the problem facing us.

Whither the Wood Burning Stove?

On Wednesday this week I travelled down to Exeter to meet Stovax, making good a promise I made to them six weeks ago. I really new sweet FA about Stovax, other than they made wood burning stoves, and I quite expected a couple of beardies wielding hammers and tongs. How wrong I was. It's now a substantial concern. The business started in 1981 when Guy Brook and his friend Miles Jennings began firstly importing and distributing stoves and then making Victorian fireplaces and surrounds. It's been been expanding ever since, some of it by starting up new companies to produce fireplace products, some by acquisition of related businesses. Stovax Holdings now employs 450 people and has become the largest stove maker in the UK. The business includes several brands: Stovax, Yeoman, Gazco (makes gas fires - does well), Redfyre (ranges) and there is another, now separate, holding company which contains a tiles business called Original Style. "In fact everything to do with fires except hearths," explained Greg Taylor, the technical director.

Greg, it turned out, is in the middle of a selfbuild and he had spent much of the past few months buried in the Housebuilder's Bible. He brought along his copy and it was marked up with post-it notes. My first thought was that I was being ambushed, and that I would be forced to work in the foundry for the next six months until I saw the error of my ways. But of course he was sweetness and light, and actually very helpful as well. I learned a lot from him during our lengthy interview.

Like what exactly?

• The difference between a wood-only burning stove and a multifuel stove. Wood burns best when laid on a bed of ash with air being injected at it from above. In contrast, coal burns best in a grate with air coming from underneath. Wood will still burn in such a grate but not as well. So a multifuel is basically a coal grate, whilst the wood grates are rather different and would be hopeless for coal. Stovax have seen sales of wood-only stoves rise steadily over the years and now they sell pretty much 50/50 (wood v multifuel).

• Solid fuel stoves can get to around 80% efficiency, but anything beyond this is technically difficult because heat is needed to keep the flue operating well.

• Virtually no one burns straight coal anymore but there are any number of clean or smokeless coals. Anthracite is a naturally occurring coal that burns very clean, but it isn't widely used these days. Instead we usually use manufactured smokeless coal pellets, known as Ancit.

• The Clean Air Act is the legislation behind a number of Smoke Control Areas where it is not permitted to burn wood or coal. You can burn smokeless fuels such as ancit, but if you want to burn wood, you need to get a stove that meets the technically demanding PD 6434 standard, which DEFRA test for in Cheltenham. These "cleanburn" stoves are then passed for use in Smoke Control Areas. It's not an easy test to pass, the cost is around £8,700, and Stovax are currently putting a lot of their stoves through this test. The more efficient a stove is the less smoke there is. "Smoke is unburned fuel" I have noted down: QED the more efficient the stove is, the more of the wood it burns and the cleaner the resulting smoke is.

• One of the keys to getting the best out of a cleanburn stove is to burn dry wood, Greg recommended getting a moisture meter and making sure that you don't burn logs with a moisture content no greater than 20%, preferably 15%. He said in order to get a true reading, split the log open and apply the meter to the middle.

• We are not about to run out of wood as a fuel. There are currently around 285,000 domestic wood stoves installed into the UK, burning around one million tonnes of timber in total each year (that's nearly 4 tonnes each stove, which seems a lot). The Forestry Commission reckons we are have the potential to burn ten times as much timber before we run into capacity constraints. They have in place a "Woodfuel Strategy for England" which should release and additional 2 million tonnes each year by 2020. Which means we are going to have to buy an awful lot of woodstoves in the next ten years if we are going to consume all this extra timber. OK, I know a lot will end up being burned commercially, but still the domestic sector will have a significant role to play.

• Stovax spent three years trying to sell pellet boilers, but the interest was minimal. They have now abandoned the technology (for the time being) and are concentrating on wood-fueled boilers, like....

• The Stockton HB. These are designed to heat hot water for the cylinder and for a number of radiators, but they are still very much focal-point room fires, unlike the utilitarian pellet boilers which ideally need to be sited in a basement. I got shown the labs where they were testing a Stockton 14. At full pelt, it burns 6kg of dry wood an hour but this belts out 14kW to heat hot water for rads and 8kW out of the fire itself and into the room.

• Greg Taylor (pictured here with the Stovax Studio 2 in the test lab) was keen to emphasise "link up." Link up? It involves adding a woodburning boiler stove to an existing central heating boiler system. The system, through gravity and series of valves, is set up so that the gas or oil boiler switches off when the stove is lit and vice versa. “Link up” allows homeowners to maintain the convenience of a conventionally fuelled boiler whilst also dramatically reducing fossil fuel bills through the use of solid fuel as an extra source of heat and hot water.

“When you get up in the morning or come home from work in the evening, the conventionally fuelled boiler can have warmed your home and given you plenty of hot water. As soon as you have the stove lit, the boiler can switch off until it’s needed again. Add solar panels and your conventional gas or oil boiler will be used even less.”

• There was a sub-text going on here which we didn't really have time to explore, but which struck me afterwards. There is a subtle difference here between a boiler and a stove. You don't really want a boiler in your living room, something I know from personal observation, having stayed in a house with what claimed to be a "pellet-stove" in pride of place next to the TV. It was noisy, ugly and just plain mechanical. So anything which ranks as a "biomass boiler" is only ever going to be of interest to a rich minority who have utility rooms and/or basements, whereas a wood-burning boiler-stove appeals to a much larger grouping. What Stovax are aiming at doing is building kit which looks like a stove and yet acts like a boiler.

• Which brings us back to the Renewable Heat Incentive which is proposing to exclude wood burning stoves but to include pellet boilers at a deemed tariff of 9p per kWh for 15 years. The worked example (on page 50) suggests that this subsidy would be worth over £1,000 a year, £15,000 in total. The logic behind excluding wood stoves is explained on page 31: These present difficulties as it is extremely difficult to monitor how much they are used (they are usually a secondary source of heat, the use of which will be optional), and to what extent they are used with renewable fuel rather than, for instance, coal. Now this second objection could be addressed by making the Stockton and its ilk wood-only rather than multifuel, but the first objection is much harder to address, especially if Greg's linking theory is put into place. Whereas the consumer seems to be saying "we want stoves, not boilers" the subsidies are going to go to the boilers. But, as we have already established, pellet boilers are really only ever going to be of interest to people with relatively large houses.

• In fact exactly the same thing can be said about ground source heat pumps which generally require large gardens. The RHI would seem to be a very generous subsidy for already wealthy people. Next week, I am booked into the government's Renewable Heat Incentive workshop, and I expect some heated exchanges on this very topic. But I digress. the subject of this ramble is wood burning stoves, and this leads us onto...

AIRTIGHTNESS
• We discussed airtight houses and how wood-burning stoves might cope. In theory, it is possible to create room-sealed wood-burning appliances (just as balanced-flue gas-fires and gas-boilers are). In practice, it hasn't happened yet, although Stovax sells optional kits for many of their stoves to take external combustion air directly to the appliance. Current UK regulations (Part J) require that there must be an additional supply of air from inside the house for any stove over 5kW but as houses become tighter this regulation will need to change for new houses. Wood burning stoves do not yet have an agreed technology to make them fully room-sealed. There are some room-sealed prototypes being made in Germany but nothing yet in commercial production. So the future of wood-burning appliances in near-Passive House standard homes is as yet uncertain, but at the moment, if you aspire to build a Passive House, you can't have a stove in your living room.

• We touched on the issue of ventilation and just how complicated it is becoming. Apparently, wood stoves tend to work fine when the house is under positive pressure, but react badly to negative pressure. This makes sense, doesn't it? So designers of ventilation systems need to be aware if a wood-stove is planned.

I hope this is a helpful guide to where things stand re: woodburning stoves. It's not a topic I have any great expertise in, and I welcome feedback from anyone with something useful to add.

More on Feed-in Tariffs

Yesterday I had the pleasure of reading through the two documents that the Department of Energy and Climate Change put on their website on Monday (Feb 1st). The first was the government's response to the Feed-in Tariffs consultation, which sets the rates for the tariffs for electricity generating technologies, principally PV, wind, hydro and micro-CHP. These feed-in tariffs are due to come into effect this April, but will apply to anyone who has fitted one of these technologies since July 2009, when the decision to switch to feed-in tariffs was made. There are no major changes to be found in the finished document, though the rates have been adjusted a little.

Feed-in Tariffs
What these feed-in tariffs essentially do is strip away the initial capital subsidies which have existed up till now and replace them with annual payments based on how much electricity you have produced. The amount depends on the technology. PV is very expensive to install and therefore gets a high rate of return, as much as 41.3p per kWh for 25 years for small retrofit installations. MicroCHP is much cheaper and therefore attracts a smaller subsidy — 10p per kWh for just ten years. The payments will be index linked. The amount you get paid will depend on what your meter says you have produced. You don't have to export all or any of this electricity to the grid, but if you do, you will get an additional 3p per kWh for your pains.

You'll have to sign a contract to say that you will keep the plant in good repair, and if you sell up and move house, the new owner collects the Feed-in Tariff. The rates paid are guaranteed for the duration of the contract, so in some respects this is a bit like buying index-linked gilts. How does it compare as an investment?

There is a worked example on page 33 showing how it might work with a small PV unit retrofitted onto a detached house. It assumes production of 2,000kWh per annum from the PV array on a house consuming 4,500kWh per annum. The income comes in via three different methods
1. The 2,000kWh produced by the PV attracts 41.3p/kWh or £826 per annum
2. It is assumed that half this amount is exported to the grid, which attracts an additional 3p/kWh or £30 per annum
3. The other half is consumed in the house which saves having to buy 1,000kWh at 13p/kWh from the electricity supplier, a saving of £130.
Combine these and the total income is £986 per annum. The question is, how much would this all cost to install? You'd probably need at 3kW system in order to generate 2,000kWh/annum - depends of course on your location and orientation. That's around 24m2, and the cost would be around £20,000 to install. So that's a return of around 5% for your investment (i.e. £1,000 a year for a £20,000 investment). With index linked gilts currently yielding just over 2%, that leaves three/fifths of the payment/savings to cover writing off the capital cost of the installation. That's £600 a year for 25 years = £15,000. That's not incredibly attractive, but it should be relatively safe. In theory, these contracts should be as safe as gilts (which are said to be the safest of all investments because they are government guaranteed), but in practice a future government might renege on the contract if it became politically expedient. An in addition, there would be added costs not factored into the equation. Servicing for one, insurance for another. With PV costing rather more than lead, there must be a risk that the arrays would get stolen, or may get damaged by hail or vandalism. There is also the issue of whether or not installing renewable technologies in the home really will add to the capital value of the house when you come to sell.

So the feed-in tariffs are an improvement on the lacklustre capital subsidies that have existed in the UK up till now, but they are still not the sort of eye watering investment opportunity that will get the City Boys throwing up PV on their roofs to make a quick buck. In reality, this is still only going to appeal to enthusiasts.

Having said that, I met one in Switzerland last week who had bought 800m2 of PV and installed it himself on the roof of a cattle shed belonging to a nearby farmer. 800m2! That'll be nearly a million quid's worth. And all because of their feed-in tariff.

Renewable Heat Incentive
The second document is the consultation for the Renewable Heat Incentive, which is similar to the feed-in tariff but for heat producing technologies, principally solar thermal, heat pumps and biomass boilers. It once again comes with a table of tariffs:
• Solar thermal to get 18p/kWh for 20 years
• Air source heat pumps to get 7.5p/kWh for 18 years
• Ground source heat pumps to get 7p/kWh for 23 years
• Solid biomass to get 9p/kWh for 15 years

There are some major differences between these subsidies and the Feed-in Tariffs. Firstly, the output of the units will be assumed rather than metered. Their word for it is deemed. This to me immediately presents a major problem, because it will be assumed that the installations will be working as designed. A lot of cheap and inadequate systems may end up being installed in order to harvest the subsidy. And, in particular, heat pumps may get installed into poorly insulated homes where they will not really be up to the job in hand.

More on this soon, but if this incentive scheme comes into effect (on the projected date of April 2011) it will effectively sound the death knell for conventional oil fired boilers which are already struggling to compete with heat pumps. This scheme will grant you around £1,000 a year for installing a heat pump. There is one ray of hope for the oil fired boiler makers and that is called FAME, which stands for fatty acid methyl ester. It's a biofuel produced from vegetable oil which can be blended with heating oil for use in domestic boilers. The paper suggests that an oil boiler could be converted to burn FAME and therefore obtain a subsidy, but details here are sketchy.

The Green Bling Tariffs

The Department of Energy and Climate Change has now published the final version of the Feed-in-Tariffs which are due to come into effect in April. The document is here. It has also published consultation, including indicative pricing, on the second leg of this subsidy, the Renewable Heat Incentive, which covers heat pumps, solar thermal and biomass.

I have yet to work out the full implications, but I suspect that the Renewable Heat Incentive will tilt the balance firmly in favour of heat pumps for anyone considering how to heat a house.

Windfarms: a small proposal

Interesting conversation last night with Anna Stanford, head of communications at RES, who I met at the Inbuilt birthday party last night. RES are behind the Wadlow windfarm development, which is local to me and which had been stalled in interminable planning negotiations.

I asked her why RES didn’t offer some sort of financial inducement to the locals in order to get them onside. She said it was not possible because it would be regarded as bribery: the planning system expressly forbids it — or at least I think that was the gist of what she was saying. Technically, it would be feasible, for a 13 unit windfarm, such as the Wadlow one, would produce far more power than the surrounding parishes would ever need, and the financial model would still stack up because wind energy, albeit in its subsidised form, is very profitable and it would still be profitable if, say, 10% of the profit, or the power drawn from one of the turbines, was used to pay the electricity bills of homes within a mile or so.

There are various models you could work on to make it fair: for instance if you were within 1000m, you would get all your electricity paid for up to a certain amount, and if you were within 2000m you would get 50%. And so on. That way the community wouldn’t just have a windfarm dumped on them, which is what the system demands at present, but rather it could sell its wind energy potential on the open market.

The reason this can’t be done essentially boils down to a problem with definitions of ownership. No one can own wind energy — it’s a common good. But surely if organisations like RES are able to obtain rights to harvest some of this energy, they should pay compensation to anyone that they might inconvenience along the way.

All things being equal, most parishes would probably rather not pay host to a windfarm built on an industrial scale, so why shouldn’t the ones that do receive some benefit?

Meanwhile, here is an image of part of a wind farm I came across in Lanjaron in Spain two weeks ago. It’s located on the edge of the Sierra Nevada, easily visible on the road between Granada and the Med. Anyone who says a windfarm is an eyesore ought to go view this one: it is simply stunning. The road into Lanjaron weaves its way around numerous hairpins and it zigzags around several of the giant turbines. At one point you appear to be travelling through the blades themselves: they seem unbelievably close and powerful. For a brief moment, you can almost dream that the future may be benign afterall.

Wolseley's Sustainable Building Centre

Tim Pollard is Wolseley’s Mr Sustainability. Here he is pictured yesterday outside his pride and joy, the £3m Sustainable Building Center, which opened in April this year at Wolseley’s UK HQ in Leamington Spa. He used to be head of marketing at Wolseley, owners of Plumb Center, Builder Center, Encon Insulation and Bathstore.com. But somewhere along the line, he got the green bug and saw a need to start promoting sustainability as a concept from within the Wolseley empire. Or, put another way, rather than just stocking what plumbers were asking for, offering them a choice of products they may not even have known existed, in the hope that they will one day (soon) cotton onto them.

Due in large part to Pollard’s campaigning from within, Wolseley have invested heavily in sustainable building materials and show no sign of back tracking from this, despite the rotten trading conditions which have forced them to lay off thousands of staff. The deal with the board seems to be this: Pollard has identified 7,000 product lines (out of a total of 500,000), which can classed as sustainable. The relative sales of these product lines will be the yardstick by which the success of the SBC will be judged. The early indications are that the sustainable product lines are increasing their market share month on month.

Just by adding Wolseley’s market presence, many otherwise marginal products become mainstream. Take wood pellets as a good example. Many people have shrunk away from installing expensive wood pellet boilers because of fears about continuity of supply. However, Wolseley have partnered with Jeld Wen to come up with a solution. Jeld Wen have lots of wood waste: Wolseley have the delivery capacity, so Jeld Wen have set up a wood pellet plant in Lowestoft and Wolseley now offer to deliver the output nationwide.

The Sustainable Building Centre is all about education. It’s not a trade counter and it’s not even open to the public as an exhibition hall — it’s appointment only. Yet they have already taken 270 bookings for visits by various groups so it’s working at virtually full capacity. Inside you will see displays of everything from renewable and low carbon technologies, SUDS, green roofs, natural paints and floorcovers, LED lighting and low-flow shower heads. In fact, just about anything you could think of with the notable exception of micro-wind turbines, a particular bete noir of Tim Pollard.

They plan to hold a number of selfbuild weekends and if you want to visit it might be an idea to check the website for more details, or make an enquiry at your local Wolseley Center.