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A quick thought on feed in tariffs.
If a value is agreed for micro power generating renewables, what will the impact be on the solar thermal industry? Would this amount to an anti-competetive subsidy for one type of technology over another? And if so, what are the wider implications?
I can see a scenario in super low energy dwellings where the feed-in tariff for PV might result in an electric heating and DHW solution, but without solar thermal as it may have a poorer pay back. This could result in solutions biased towards oversized PV in situations where solar thermal provides a more common sense fit.
Any thoughts?
At a meeting last week, the message from BERR’s side of the table was that the consultation on Zero Carbon (originally planned for summer, then autumn) is now unlikely to come out until 2009. That’s going to give industry at most 6 years to tool up to delivering zero carbon. Given that ministers are long past the point of no return on this, it’s extraordinary that by delaying this consultation they’re making things even harder for themselves and for developers.
This is the second time that I have written this post, as I had not saved the first version and then browser magic lost it… I haven’t posted for a long time and wanted to avoid a negative post for my return, but unfortunately events have determined this otherwise.
Last week I undertook BREEAM for Offices training to plug some holes in my various accreditations, but was woefully underwhelmed by the quality of the BRE Training. Read the rest of this entry »
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.
The UKGBC is launching plans for a Code for Sustainable Buildings to “address the confusion arising from the myriad of different green building standards.” Although they’ve used the name, this isn’t the same Code for Sustainable Buildings that we were promised a few years back and that was eventually pared down into the Code for Sustainable Homes. This is an “open-source” UKGBC-managed standard which could then be used in other standards.
Reading between the lines, the UKGBC have just pre-empted a situation in which BREEAM is adopted wholesale as the basis of a future Code for non-residential buildings (a situation like we saw with EcoHomes and the CfSH). It looks to me like they’re looking to usurp BRE’s place as guardian’s of the public interest when it comes to building performance and I suspect the use of the words “open-source” is a stinging reference to BRE’s increasingly mercenary approach. So take that BRE - you’ve just been King-slapped.
Or am I just looking for drama on an otherwise dull Tuesday?
Developers are taking a hard look at their pipelines in an effort to find savings and many projects are grinding to a halt. Redrow, Taylor Wimpey, Bovis, Barratts, Persimmon - each laying off thousands from their workforce. There’s no doubt that the credit crunch is taking a deep bite out of the construction sector. In addition, oil and energy prices are exacerbating the situation, rising continuously for the foreseeable future.
All this comes at a time when the UK is looking to new build projects to help it meet a significant proportion of its carbon and renewable energy targets, some of which are legally binding and carry fiscal penalties for failure.
I’m now an accredited Code for Sustainable Homes assessor. Is that a good thing? I’m not sure.
For a while, I have suspected that the thermal efficiency requirements for Code 6 would almost certainly require MVHR. But I was always dimly aware that I hadn’t actually done the numbers and so couldn’t be sure. Now I am: no MVHR means no Code 6.
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 »
The housing minister, Caroline Flint has ‘confirmed’ the proposals for mandatory Code for Sustainable Homes assessments for all new dwellings from May 1 2008. Read the rest of this entry »
There seems to be much confusion regarding the forthcoming status of the Code for Sustainable Homes. There are many references to Government making a Code assessment mandatory from April this year.
But is this truly the case?
[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 »
I’ll keep this short to ensure that it does get posted, but I suspect that I could rant on this till closing time on Friday night. For a recent renewable energy assessment for a client I finally took the time to review the potential for air source heat pumps to deliver carbon reductions and I don’t like what I found. Read the rest of this entry »
I posted extensively last year about the no off-site renewables issues enforced by the Treasury. There is little to report on this as yet, except that as a direct result of the blogging and discussions with Paul King by myself and Julian Brooks we were invited to join the Green Building Council Task Force to review the issues and report to Government.
Can’t say anything about progress, but it’s exciting stuff and we are pleased to be involved.
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.
Back in the UK for project meetings, I arrived at my inlaws’ house in Dorking yesterday evening and within minutes my father-in-law was spreading the Telegraph on the table, pointing to the article about how long efficiency measures take to pay back. Phil at the Sustainability Blog has already commented on the RICS claims and I agree with him.
And here’s first hand proof of the damage their histrionics have done: as I explained to my father-in-law that the RICS study was making unreasonable assumptions (e.g. simple payback calculations) his eyes glazed over. Why? Because the soundbite had already done its job. Nevermind the VAT debate or discussion of EPCs, he’s now more convinced than ever that there’s no point in pursuing any of this eco-treehugging-mumbo-jumbo as it’s obviously frivolous and expensive.
Thanks RICS.
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.
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