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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Baroness Wilcox, the amendment’s sponsor, has now withdrawn it, but only on the condition that the Government meet specific terms in their own amendment, which they’re expected put forward on 5 November.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):
If you haven’t checked out Michael Willoughby’s biomass blog, Woodfuel Magazine, you should. It’s an RSS feed well worth subscribing to. Keep it up, Michael!
Over recent weeks it’s become clearer which way the wind is blowing on private wire. Although BERR and OFGEM have set themselves an end-of-year deadline for finalising changes to the licensing regime, it’s possible to get a feel for which way they’re headed. Here are some of the key bits:
On a project at Fontenergy we’re looking at some small scale gasifiers that claim to have overcome the traditional problems associated with wood gasification. While doing some research I came across this manual from the Federal Emergency Management Agency in the US, with detailed instructions of how to convert your car, truck, or tractor to run on wood gas in the event of extended petroleum shortages. The practice of using wood gas in internal combustion engines was very common in Europe during the Second World War (apparently 95% of mobile farm machinery in Denmark ran on wood gas - I love Denmark) and this guide is aimed at preserving that knowledge.
I’m taking a sickie, grabbing the tool box and heading for the garage.
Love them or hate them, liquid biofuels are increasingly being put forward as a renewable fuel for CHP. Currently they’re eligible for ROCs and so appear to be considered renewable by BERR and OFGEM.
But when I spoke to the SAP team at BRE, not only did they confirm that liquid biofuels aren’t considered under SAP, they also said that “because of mounting doubts over the extent of emissions from biofuels”, you have to use the emissions factor for oil when carrying out your SAP calcs. Did they expect the treatment of biofuels to change for the 2010 review of SAP? Adamantly, they did not.
Then I called the BREEAM helpline. They told me that liquid biofuels also aren’t considered under the Code for Sustainable Homes. So no help in scoring points under ENE1 or ENE7.
So liquid biofuel CHP is eligible for ROCs but will do little for your Part L and Code requirements. Without achieving these requirements, the case for biofuel CHP for new buildings is severely undermined. Obviously this situation could change. With CLG on the lookout for ways to meet the 2016 zero carbon homes target, there might be considerable pressure applied in favour of making biofuel renewable under SAP. But for now the official line is that biofuels are not a solution for carbon reduction in new build.
A Poyry report out today finds that by installing new CHP at just nine industrial sites around the country we could meet the electricity demand of 2/3 of the UK households and reduce gas imports by half. CHP is cleaner, cheaper, and more efficient than nuclear with no toxic legacy. It’s also much much faster to deploy. So shall we?
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.
If you build to Passivhaus standard, there’s no point in putting in a wet heating system. In fact, the key to the economics of Passivhaus design is that a conventional heating system is rendered redundant: you’re supposed to use the resulting savings to help fund the efficiency measures. Instead of a boiler and radiators you might only need a small electric heating coil in your mechanical ventilation system.
Level 6 of the Code for Sustainable Homes is modelled on the Passivhaus standard. As a result, until the Code changes, you’re likely to see more and more developers trying to move towards electric heating systems. You might argue that given the quantities of electricity we’re talking about (15 kWh/m2.yr), even if you source the electricity from the grid, it’s no carbon catastrophe. Unless you consider the bigger picture.
Making new buildings zero carbon is an excellent requirement, but by focusing our efforts (and a hell of a lot of money) on ratcheting down the heat demand from new buildings, we throw away the huge opportunity of using new developments to slash emissions from existing stock. Read the rest of this entry »
My first day back in London and I’ve spent the morning schmoozing at a publication launch just off the Mall. Five minutes out of my cattle stall and I’m already moving and shaking. It was an event to publicise the TCPA’s new document, Community Energy: Urban Planning for a Low Carbon Future, and it attracted quite a crowd including MPs Nick Hurd and Keith Hill.
During the presentations and panel discussion, most people in the room seemed to feel that local authorities have the pivotal role to play in the creation of low carbon distributed energy networks. I totally agree, but I think we were missing part of the picture.
I’ve been spending some quality time with spreadsheets and have an update on the way building regs for housing treats CHP. It’s not as simple as I thought here, although the result is similar. The incorrect method I wrote about a few weeks back is still in use, but it’s different from what’s happening in SAP 2005. Here’s a breakdown:
Today Lord Turner’s panel met for the first time to discuss a concrete strategy for fufilling the UK’s commitment to reducing emissions by 60% by 2050 (and to consider upping the target to 80%). With around a third of UK emissions coming from housing, this sector will inevitably play a key role in their strategy. You might think we could rely on the Code for Sustainable Homes to get us there - after all, if all homes from 2016 are Code level 6 then there will be no net emissions from new housing. But unfortunately new homes are only a small part of the problem.
The graph below illustrates the predicted emissions from the housing sector by age of housing stock for the period 2002 to 2050. It shows that the overwhelming proportion of emissions will continue to come from houses built before 2002. The dotted lines represent the emissions from all housing required to achieve a 60% and 80% reduction in emissions vs 1990 levels. Emissions from each band decreases over time due to demolition.
Figure 1. Carbon emissions from housing sector by age of housing stock, 2002 - 2050
Communal wind turbines are currently of no use when trying to achieve Zero Carbon status for Stamp Duty Exemption. Here’s why… Read the rest of this entry »
Greenpeace has created their version of a model town, stitching together examples from all over the UK. It’s a very cool combination of flash pages with lots of case studies, animations, and videos. Worth a wander.
[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:
The Draft Statutory Instrument (DSI) for Stamp Duty Exemption for Zero Carbon Homes, announced at the last budget, will undermine the majority of attempts to deliver the greenest of housing. The DSI doesn’t appear to be available online, but the link is to a copy we acquired from the Treasury after badgering them.
The DSI is to be laid before Parliament at the end of next week for Committee approval by the end of the month. It is at best a misguided piece of well-meaning legislation that will do more harm than good, or at worst a genuine attempt by central Government to limit the loss of stamp duty receipts from too many zero carbon homes.
The Green Building Council published a response in July to the Draft Statutory Instrument (which comes into force on October 1) for stamp duty exemption as proposed by our now Prime Minister in the last budget. I wish I had read it more carefully at the time…
Colleagues and I have been trying to disentangle the most cost-effective routes to achieving Code Level 6 of the Code for Sustainable Homes for a number of far-sighted and sincere clients who want to deliver the most efficient housing possible, and not just for those that can afford it.
Anyway, the budget announcement stated that zero-carbon homes would be exempt from stamp duty, which in reality is nothing more than a political gesture as the costs involved outweigh the stamp duty savings. Originally, the Code was written to allow for accredited offsite renewables which could demonstrate clear additionality, to be acceptable in achieving true zero carbon status. This was a bold step that, despite the uncertain mechanics of administration had the potential to allow developers the choice of investing in off-site renewables. Imagine being able to deliver say 30-50% CO2 reductions for the cost of a planning requirements of 10%? Or even a 100% reduction for an acceptable extra over to secure a particularly plum site. Too good to be true perhaps?
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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