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There have been further amendments to the Energy Bill in the Lords in connection with feed-in-tariffs. The one year implementation deadline is back in. Excellent news as the detail of how FiTs are implemented will almost inevitably be bogged down in long discussions between government and power suppliers - a one year limit should focus minds.
Also, the 50kW limit on capacity of gas CHP has been lifted. This means Read the rest of this entry »
Last night, Lord Hunt came back with his amendments to the Energy Bill and, as promised, here’s an update. For electricity feed in tariff, he’s proposed:
- Feed in tariff for renewable generation up to a maximum of 3MW (excellent).
- Qualifying technology: biomass, biofuels (oh dear), fuel cells, photovoltaics, water (including waves and tides), wind, solar power, geothermal sources, combined heat and power systems with an electrical capacity of 50 kilowatts or less.
- No timetable for implementation (as far as I could see - is it buried in there somewhere? What will the Baroness say?)
On a heat incentive:
Away from the fanfare around Ed Miliband’s announcement that a feed in tariff (FiT) is on the way, the Lords have been debating an amendment to the Energy Bill that has the support of Conservatives, Lib Dems, and even some Labour peers.
What’s in the amendment? It says the Secretary of State has one year from the passing of the bill to bring in a feed in tariff. And the qualifying technologies, their maximum capacity, and their level of support are left to the Secretary of State to decide with no specified cap.
Despite wide support, it was clear that the Government wouldn’t officially get behind the bill as it wasn’t their idea. In fact, as recently as June the Government were firmly against a feed in tariff.
Baroness Wilcox, the amendment’s sponsor, has now withdrawn it, but only on the condition that the Government meet specific terms in their own amendment, which they’re expected put forward on 5 November. However, if the Government doesn’t fulfill her demands, she will reintroduce her original amendment. Here are her terms in a nutshell (my comments in italics):
Yesterday BERR and OFGEM released proposals for changing the way the electricity regulations work with regard to distributed energy generation. This is particularly important because it’s BERR’s first public reaction to the Citiworks ruling by the European Court of Justice two weeks ago.
[update March 20: I've looked further into how SAP treats CHP and written it up here. So while the method described below is being used elsewhere in the industry, the criticism doesn't apply to SAP.]
I’ve written on this topic before but maybe I didn’t succeed in making clear just how far off the mark the standard method is when estimating carbon emissions from CHP. Why does it matter? Here are some reasons:
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Right now, big developers and the Housing Corp are assuming CHP can get them to level 4 under the Code for Sustainable Homes and this may not be true.
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These emissions figures can determine whether or not a scheme gets planning permission or passes building regs.
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The nascent micro-CHP industry (expected to be worth £2billion per year across Europe) is using this flawed method to back up its sustainability claims. Changing from a commonsense approach to the much more forgiving “standard” approach explains why the first Carbon Trust interim report on the micro-CHP field trails was so bleak and the second was so rosy.
There’s a good chance that, if I’m right and the standard approach is flawed, when the CLG and BRE realise their mistake, the rules will change, leaving public and private sector developers and the micro-CHP industry with a very costly mess to clean up. Read the rest of this entry »
Much later than planned, but here it is. In summary, micro-CHP saves 5% to 10% of carbon in large inefficient houses but only if you use a flawed methodology and give yourself extra-extra credit for displacing grid electricity. A few of the key findings:
- The trial has demonstrated that the carbon and cost savings from Micro-CHP are generally better for buildings where they can operate for long and consistent heating periods.
- In small commercial applications, the field trial has shown that Micro-CHP systems can provide typical carbon savings of 15% to 20% when installed as the lead boiler in appropriate environments.
- The domestic Micro-CHP systems monitored in the trial have the potential to provide typical carbon savings of 5% to 10% for older, larger houses with high and consistent heat demands (over 20,000kWh/yr).
So since the last report, the Carbon Trust has toed the industry line that the 0.568 figure should be used.
There’s some very interesting output from the boiler field trials in the report as well. In particular, the boilers they’re monitoring are generally performing 4% to 5% below their SEDBUK rating.
Phil Clark and Fulcrum have put together a fantastic list of upcoming proposed policy changes relevant to construction. Though I couldn’t find the attached doc he talks about: Fulcrum’s housing chart - where is it? Phil’s promised to keep the list updated as more information is released.
That’s just saved me a pile of research this morning, Phil. Thanks.
[Update March 20 - while it's true that SAP gives misleadingly high emissions savings for CHP, I got the methodology wrong. See an updated post here. Points 3 and 4 below are still valid.]
The SAP results for dwellings using CHP are badly skewed. This may cause large developers to formulate strategies for meeting the Code for Sustainable Homes which fall well short of the targets.
Doing some research this week, I read the Housing Corporation’s report on the estimated costs of meeting various levels of the Code for Sustainable Homes. It’s an interesting document, but at a certain point I was confused by their claim that you can meet the carbon reductions required by code level 4 (i.e. a 44% reduction in DER relative to TER) just by using gas CHP. In fact, when I looked closer I found that in some cases, they were claiming an emissions reduction of over 50% - an extremely high figure. Something closer to 10 and 15% is much more reasonable, unless you want to get Orchardesque.
The source of these wild claims is the Government’s Standard Assessment Procedure for dwellings - SAP 2005. As hinted at in the CHP debate running in the BSJ over the summer, SAP does some funny things when it comes to CHP. Have a closer look at the SAP worksheets and you find that SAP:
Over the summer there was a debate between some big names in engineering over whether combined heat, cooling, and power (CHCP) using absorption chillers actually saves carbon. The theory goes that because engine size is usually dictated by the base summer heat load, the additional heat load from the chillers allows you to upsize your engine and generate more low-carbon electricity throughout the year.
However on a current project, we’re looking at the feasibility of installing a district heating and cooling network, including installation costs. And one thing is clear: regardless of whether CHCP saves carbon, the capital cost of cooling is unaffordable.
I’m doing financial comparisons of energy systems on one of our projects. It’s a pretty standard part of our work but this morning the precision of the figures appearing in my spreadsheet strikes me as particularly specious because it doesn’t tell the whole story. Sure, clients need a comparator and you can’t preface every report with a thesis on complexities of the energy market (not that I’m capable) but just the same these results are making me uneasy and here’s a short list of reasons why:
In Building yesterday, a study by London South Bank University says a quarter of schemes in London are exceeding the 10% target. The article states:
In total the study, undertaken by London South Bank University, looked at 113 detailed energy statements for schemes that had been given planning approval.
Erm, but none of those scheme has been built yet. And currently there’s no mechanism for enforcing adherence to the commitment by developers - unless it’s written into a Section 106. This enforcement mechanism is a tricky issue that hasn’t been resolved as far as I know. The study also finds that:
…the most effective technologies at cutting carbon are CHP and CCHP, particularly where biomass fuel is used.
Fantastic, and I’m looking forward to seeing more biomass in London. We’ve specced it on a number of jobs, the first of which is up and running. But I can say that using biomass heating (never mind biomass CCHP) brings its own logistical tangles. It’s one thing to tot it up on a spreadsheet and another entirely to bring to fruition.
Without succumbing to the pessimism that seems de rigeur when blogging about the government’s or the GLA’s green policies, I’d just like to add a note of caution. The schemes have been granted planning permission but are by no means home and dry. A follow up survey is needed to see what’s actually built.
What’s going on?
There’s been a fierce debate among energy bods this summer over the environmental effectiveness of combined heat and power (CHP) and CHP with cooling (CCHP) – a debate closely tied to assumptions about the carbon emissions associated with grid electricity in the UK.
What happened?
As noted in this blog in May, Arup associate director James Thonger opened up with a broadside aimed at the GLA policy of requiring CHP and CCHP on new developments. In particular he refuted LCCA claims that gas CHP saves 54% of carbon relative to grid electricity. The LCCA is headed up by Allan Jones, former green god of Woking and now darling of the London Mayor, who didn’t take the criticism lightly.
Just heard from the folks at the Carbon Trust who are doing the micro-CHP field trials. The release date for the next interim report has been pushed back to the end of August with the methodology to follow some time after. Advise not holding breath.
There was an article in the Guardian last Saturday (thanks to Tessa for spotting it) by Alex James, the bassist from Blur, about having an architect come to his home to give green advice. It’s a scheme run by the RIBA where architects provide green advice in exchange for a donation to charity. At first glance this sounds positive. Certainly it’s a great channel to spread information on energy efficiency.
But things get a little weird when the article states that thick rubble walls keep the house warm in winter - which they don’t. Then architect George Stowell suggests that Alex installs a biomass CHP unit to generate his own electricity on site from wood chips. But there aren’t any commercially available biomass CHP units on a single house scale (or even twenty times that big). He may have meant biomass heating, but it’s a hell of a mistake to make, recommending something that doesn’t exist.
It might be better to send a services engineer. CIBSE should consider something similar to the RIBA programme.
Via Tom N, a great article in BSJ on whether CHP (and CHP + cooling) actually has as much potential to reduce carbon emissions as the industry (and Ken Livingstone) would have you believe.
In general, I agree with James Thonger’s conclusions. However… Read the rest of this entry »
According to online energy auction house BuyEnergyOnline, during April 2007 UK gas wholesale prices rose by just 1% while electricity prices increased 13%, making the widest spark gap since deregulation. Read the rest of this entry »
The people in charge of the micro-CHP field trial at the Carbon Trust say their next interim report will be delayed until early June with the calculation methodology to follow soon after. So we’ll have to wait a little longer for the verdict on micro-CHP. Interestingly, the MicroGen units are still in the trial so maybe it will become clearer why BG Microgen closed down.
I saw on zerochampion that GTC Europe have got together with Cambridge Consultants to produce a single-house micro CHP unit. The key difference between this unit and the Mircogen or Whispergen is that it’s based on a Rankine cycle engine rather than a Stirling engine.
It’s got a similar electric-to-heat output ratio as the Whispergen and Microgen (1 kWe/9 kWt) but they claim that it operates at high efficiency at part load. They also say 2000 units will be available for sale by the end of this year at around €5000 each. It’ll be impressive if they hit the release target as the unit seems to have come out of nowhere. Read the rest of this entry »
It was announced this month that BG Microgen are closing their doors. Microgen is one of two major players in the much hyped and still nascent domestic-scale CHP market. Why would a company backed by British Gas, with over £50m already invested, and poised to take a significant share of a huge market (so we’re told) close their doors just like that? Read the rest of this entry »
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