On Carbon Offsetting

A couple of weeks ago I went to a gathering organised by Cambridge Energy. The subject of debate was Carbon Offsetting: fix or fig-leaf? And very interesting it all proved to be.

I am of the camp that thinks it's pretty much fig-leaf. The first person I bumped into there was Andy Brown, an old acquaintance of mine who now works at Cambridge Architectural Research. Andy is even more of a fig-leafer than I am. He runs something called Cambridge Carbon Footprint in his spare time; I am not completely clear what it does but one thing it doesn’t do is sell carbon offsets.

The speakers at the event were a mixed bunch. Fiona Harvey of the Financial Times gave a run down of some of the carbon offset scams she had uncovered recently. These included a company selling offsets which consisted of sequestering CO2 by pumping it down into oil wells, when the real purpose of this operation was to increase the gas pressure in the wells and thereby help to extract the last of the oil down there.

Then Michael Schlup told us about the Gold Standard, a sort of UN backed quality assurance scheme for carbon offsets. I wasn’t convinced but he made the interesting point that you can’t realistically offset within Europe because the total amount of CO2 released is already capped (at least in theory, by Kyoto): it therefore only works in territories where there is no capping. Hence so many carbon offsetting schemes being Third World projects.

Now many people are cynical about rock stars offsetting their world tours by planting mango forests in India, but are happy to accept the principle of offsetting home produced renewable energy in order to obtain zero carbon status for a housing project. But logically, it’s all offsetting. As is buying electricity from a green supplier. Unless you aim to live entirely off grid and entirely without recourse to fossil fuels, which most people think is virtually impossible in the Western world today, then you can only approach being carbon neutral by trading your excess renewable power or biomass sequestration project, or by getting someone else to do this for you.

So despite all the scams and the indulgences it attracts, the principle of offsetting is sound. But it still sticks in the craw: the idea that I can burn more carbon if you do something to absorb that carbon. There is, whether you like it or not, something rather unpleasant going on here. It has been expertly satirised by Andy Brown’s son, Alex Randall, who runs the Cheat Neutral website.

This debate is particularly relevant to the Code for Sustainable Homes because it seems happy to accept some forms of offsetting but not others. This is difficult territory.

• The CSH accepts that it’s not possible to have a house generate all its electricity all the time, so it is permissible to trade any surplus you generate on sunny or windy days with the National Grid. Like it or not, that’s an offset.

• But the CSH also recognises that is impractical for every Code Level 6 house to be expected to generate renewable power, so the offset is extended to include community power schemes, such as CHP and district heating. So we have moved a level further out: they now accept offsite offsetting.

• How far off site can this renewable power plant be situated? It seems churlish to impose a maximum distance, so they have to accept that it could be many miles away. But how far? How about out in the North Sea?

By now, you can see that we are straying into very difficult territory. The CSH zero carbon definition is adamant that it won’t allow schemes simply to sign up for a renewable electricity tariff, because anyone can do that anytime. Somehow they want to be able to ensure that the renewable power generated for the scheme is unique and is additional to any other source, but this is much easier said than done. How do you enforce an individual home owner, let alone an entire housing scheme, to finance, say, an off shore windfarm? Especially in a country where we are all free to switch power suppliers at the click of a mouse. The government’s definition of zero carbon hinges on this conundrum and I don’t think anyone is going to be able to come up with a compelling definition, because the rules they dream up will look arbitrary and nonsensical.

The problem is of course that once you accept one bit of the offsetting model as being legitimate, then logically it’s all legitimate. After all carbon molecules don’t much care what happens to them and as far as CO2 reduction is concerned, a carbon molecule sequestered in an Indian mango forest is just as good as one saved from being burned in a power station because you have PV on your roof.

I don’t have a lot of sympathy for the government here. After all, it was they who dreamed up this silly target of the zero carbon home, something that is impossible to exist without embracing the concept of carbon offsetting. They now want to pick and choose which offsetting bits they like and which they don’t. I will rather enjoy watching them wriggle on their own hook.

Damned difficult, this carbon offsetting.

Michelle Kaufmann

Check out this video link if you want to know more about California’s answer to Bill Dunster.

Energy saving advice

Dear Mr Brinkley. Thankyou for filling out our home energy check questionnaire: an important step towards using less energy to heat, light and power your home. Using the information you’ve provided, we’ve come up with a practical look at the energy you use and can save at home.

About a month previously I had responded to a questionnaire that had arrived, unsolicited, by mail from the Energy Savings Trust. It asked me lots of questions about my house and suggested that if I send it back to them they will supply me with a mini energy audit. Only I don’t think they called it that.

I was interested to know what they would say because our house is arguably an interesting case. Built in 1992, it was certainly someway in advance of building regulations at the time. In particular, it incorporated underfloor insulation (not mandatory until 2002) and low-e double glazing (back when low-e was cutting edge). The walls had a little extra insulation and the oil-fired boiler heating system was reasonably well designed and included zone control, as well as thermostatic and time switching. It’s a well-built house and it probably rated as a Best Practice for 1992 sort of house, but certainly not an eco house.

The question that I was interested to see answered was what the EST would suggest that I did to upgrade the house. In fact, they have only made one suggestion. That is that we upgrade the boiler to a condensing boiler for a saving of £85 a year. Or, in terms of CO2, 0.6 tonnes.

Funnily enough, we did consider installing a condensing boiler when we built the house. Back then, there was only one oil-fired condenser on the market, made by Geminox, a French manufacturer. Our green-tinged plumber, Norman Cox, was keen for us to fit one, but in the end I took the decision that it wasn’t worth paying the extra £1,000 or so required to fit — cash was tight back in 1992 and I had heard one or two stories about the early Geminoxes which didn’t inspire confidence.

We ended up with a Boulter Camray (now part of the Worcester Bosch group) which has been chugging away these past 15 years. It gets an annual service (cost around £60 plus parts) and it occasionally breaks down. The last time this happened, I enquired from Shelford Heating about replacing the boiler with a condenser but was told that not only would we have to bear the cost of a new boiler, but that the oil tank would have to move because the position we placed it in in 1992 (right next to the house wall) is now regarded as a fire hazard (Part J of the building regs having been “upgraded”). Not only would that double the expense but there is no obvious place in the steeply sloping garden to place a new oil tank. It would in fact represent a major piece of civil engineering. So a replacement boiler would probably end up costing us around £8,000. Hmm. Should have fitted the Geminox 15 years ago, shouldn’t I.

Anyway, I am slowly but surely getting around to the point of this post. The Energy Saving Trust gave us a C rating, based on what I told them. This is sort of similar to the rating we would be getting from an energy performance certificate. I have no quibbles with that: it was what I expected. But the point is that they only made the one suggestion for improvement, which was to replace the old boiler with something more efficient. The saving was actually pretty minimal. Either with or without a condensing boiler, our not very old house still uses a fuck of a lot of oil. Around 2500lts each year (that’s just over a tank full). That converts to just over 25,000kWh, which converts to 7 tonnes CO2 per annum. The Energy Savings Trust estimation is pretty accurate on the size of our oil bill (just about £1,000 with oil at 36p/lt) but grossly underestimates our CO2 footprint: they suggest just 4.1 tonnes of CO2 per annum. I reckon it is over 7 tonnes. Why should that be? Do they use different conversion factors to me? I’m on 0.265kg CO2/kWh, which is the “industry standard.”

So my poser for the day is what should happen to houses like ours? If it was built to Passivhaus standards, or Code Level 4, and was still heated using an oil-fired boiler, it would be burning about a third or even a quarter of this quantity of oil, releasing maybe just 1.5 tonnes of CO2 a year to get space heating and hot water. So, although our house is probably more energy efficient than 90% of the UK housing stock, it still performs miserably in terms of what could be done. But there appears to be no upgrade path apart from fitting a condensing boiler, which really only makes a marginal difference.

I don’t have an answer to this, but it does highlight the enormity of the problem. What exactly do you do to a house that already has cavities full of insulation and has 200mm of the stuff in the loft, but still eats energy like it’s going out of fashion?

My hot tip for property investors

Here’s an interesting little graph, which I gleaned from the Oct 07 edition of Housebuilder magazine. It shows the extraordinary transformation in the supply of new homes in Britain over the past decade. In 1998, nearly half of all new homes were detached. Today, the figure is just 20%. In contrast, flats have gone from around 18% of the total to just under 50%. Effectively, the positions of detached houses and flats have swapped over, whilst terraced houses and semis have stayed much as they were, at least in terms of proportions of overall mix.

Now there are well-known reasons for this turnaround. 1998 marked the start of the brownfield land building campaign and the move towards densification. Or put another way, it marked the beginning of the end of developers being able to buy green fields and plonk estates of detached houses on them at very low densities.

Nevertheless, I am still struck by this graph. The turnaround really is quite dramatic. And it does make you wonder whether this emphasis on building flats is sustainable (in the economic sense). It would seem that, all other things being equal (i.e. pre 1998), housebuilders would be knocking out masses more detached houses than they are, but the constraints of the planning policies have more or less put a stop to this. Presumably the underlying demand for detached homes is as large as ever: given the choice, most people would probably rather bring up a family in a detached house with a garden rather than a flat. And most young flat dwellers would probably envisage themselves moving into a detached house if and when they start families. That looks as though it’s going to become an increasingly difficult aspiration to meet. So if this new housing mix remains in place — or even becomes more pronounced over the coming years — then expect to see the relative value of detached houses increase, and flats to decrease.

How’s that for a bit of financial forecasting? Revisit this blog in 2017 and see if my prediction works out.

Can a bathroom makeover be eco-friendly?

I was recently asked to write an article on “How to Give Your Bathroom an Eco-Makeover”. My first reaction was to blanche. How can anything as superficial as a “makeover” be eco-friendly? The eco-cause, green building, sustainability, these are important issues that cannot be taken so lightly as to be associated with a quick lick of organic paint and some recycled batik cushions.

But then I paused and thought a moment. I have for a long time believed in the maxim that change is a process, not an event. I also believe that we have to change the way we build houses and live in them. If for no other reason than that there is no good reason to go on the way we are. Maybe its is a generation thing (maybe I am just mean), but I abhor waste and the way we build houses is massively wasteful. They waste materials, many of which are from finite resources, they waste energy, again mostly from a finite resource, and most importantly they waste money. And they produce waste, and lots of it.

The Government is forcing the change with the Ecohomes standard, The Code for Sustainable Homes and significant stiffening of the Building Regulations. Mark Brinkley has written at length in this blog about the anomalies in these new codes and how they are more or less ineffective. Most of which I agree with. But he makes my point for me. These new standards are making the necessary change an event – zero carbon by 2016 – without winning the hearts and minds necessary to make it happen. They certainly haven’t won Mark Brinkley’s heart or mind, and as I travel around speaking on sustainability I find he is not alone.

I am about to make a presentation to a group of building control officers on the Ecohomes standard. The reason? Their boss had caught another of my presentations and had not realised what the standard entailed or how building control officers would be involved. Again, the change has been dumped on them without any attempt to justify its aims or to win them over to the cause – or, it seems, even to provide them with basic training as to what the standards contain. What will happen is that the building control officers, upon whom the self-builder or developer will depend, will be poorly informed and resentful. As a consequence they will, at best, be unhelpful and maybe even obstructive.

I have experience of other quality management systems and what happens is that people do as little as possible to comply and spend all their time, and money, finding ways around each particular requirement. That already happens with Building Regs and always has. It is a fence we have to jump over and obviously we clear it by as little as possible. Very rarely, almost never, do you find any attempt to voluntarily exceed the standard. The same is set to apply to the Code and Ecohomes, although the opportunity still exists to “sell” the idea as something more than a minimum standard that we are dragged, kicking and screaming, to. We could be encouraged to take it on with enthusiasm; as a means of building better homes, less wasteful homes, homes that will last 100 years.

To take an example, I have a client who is converting a cob barn to what will be a lovely home. The problem he has is that building control has no knowledge of the thermal performance of a cob wall (for the uninitiated, cob is a mixture of clay and straw formed into walls 500mm to 700mm thick and rendered with lime. It is a building method some 400 years old that is still fairly common in the South West of England). Cob is know to provide a relatively constant internal temperature and consequently needs little energy to heat – the cob providing good thermal mass. What my client has to do is pay Plymouth University to test the cob walls and arrive at a U-value to convince building control that this 200 year old building is good to go. Not only that, but everyone, wanting to use cob has to do the same thing. You would think that building control would learn that cob over 500mm thick complies, but no. BRE has not tested it so it does not appear in the tables, and therefore has to be tested afresh every time.

The Code is about building sustainable homes and here is a family trying to do exactly that and being stymied at every turn.

There are anomalies in the standards, bits that are unworkable and requirements that appear to make no sense. But there is also a lot that is good in them. Measuring the amount of energy and water we use has to be a good start. Raising the standard of noise insulation and encouraging the use of brownfield sites also have to be good ideas, as does encouraging the use of materials from sustainable sources. But of course this great Government of ours is deaf to the pleas that the anomalies need to be addressed. Thereby condemning the Code to be no more than another pile of bureaucratic paperwork that has to be complied with.

If, like me, you believe that changing the way we build and power our houses is a good idea – because it is a good idea to leave something for our children’s children to build with – then embrace the Code. Work round the anomalies, step over the unworkable bits and move on. In essence it provides the basis for a new way of thinking about how to build, and in time, maybe, it will evolve into a useful document.

Have thought all these thoughts, I returned to the article with a fresh view. Change is a process and it has to start somewhere. A small change that is successful is more likely to lead to more change than a big change that fails. So giving your bathroom an eco-makeover is actually a great idea. It enables the homeowner to address all the key issues – energy, water and materials – in microcosm. The project is likely to be successful as it is doable, affordable and the changes wrought will be effective. It is to be hoped that the success will lead to further projects, more success and a realisation that the eco-cause is not exclusively for people with beards and open-toed sandals.

Drilling Down into the Code: Part 3

The Code for Sustainable Homes is a hotch potch. Whilst zero carbon and, to a much lesser extent, water use reduction have been discussed at length, if you were to build the most energy and water efficient house possible, you’d still only score 44% of the maximum available eco points. That would get you to Code Level 1. Code Level 6, the top level, requires a score of 90%.

So how would you go about garnering the other percentage points required to lever your house up from Code Level 1 to Level 6?

The answer is that you have to accumulate credits (of varying value) by undertaking all manner of other actions. Some are relatively easy:
• Provision for cycle storage — score 2.5%
• Provision of a home office — score 1.25%
• Provision of recycling bins and a compost bin — 4.75%
• Use EU approved insulation — 0.6%

Others are more taxing and potentially a lot more costly
• Build to Lifetime Homes standards — 4.75%
• Build to Secured by Design standards — 2.25%
• Improve on Part E sound regulations — 4.75%
• Use A+ rated materials from the Green Guide for Specification — 4.5%
• Build into the basement or the loftspace — 2.65%

You can only afford to lose 10% of the credits available if you want to qualify for Code Level 6. As there are likely to be some areas where your site cannot score at all, the likelihood is that designers will be forced to incorporate practically every feature mentioned in the Code. The elbow room for trade-off is remarkably limited.

This is where the Code gets into sticky ground. A lot of these features — there are 34 tests applied in all — are concerned with good design and best practice, but not necessarily to do with sustainability. For instance, having your builder signed up for the Considerate Contractors Scheme (worth 2.25%) is all very well but doesn’t really make much difference to climate change. So why is it being included in the Code?

And the requirement for A or A+ rated materials is effectively going to blacklist an awful lot of C rated materials. I am not sure the PVCu manufacturers have yet twigged this, but the Code has it in for them.

How should we manage water use in the home?

The more I learn about the Code for Sustainable Homes, the more uncomfortable I get. I mentioned that I had been in on an interesting seminar last week, on the water use guidelines set out in the Code, and this week I investigated a little further, armed with an Excel spreadsheet.

Water use is one of two mandatory aspects of the Code (the other being energy use). Mandatory, in this instance, means that you have to meet certain targets as regards notional water use in order for the house to gain a particular Code Level. It’s no good building a zero carbon house if it fails to meet the water use standards as well.

The target water usage levels that the Code demands go like this:
• Levels 1 and 2: theoretical 120 litres/person/day
• Levels 3 and 4: theoretical 105 litres/person/day
• Levels 5 and 6: theoretical 80 litres/person/day

Now I guess many people have read the code and noticed these figures and probably thought very little more about them. I certainly hadn’t until I sat in on this seminar last week. Until then, they were just numbers jumping at me off the page: they didn’t relate to anything or any actions. But my eyes have been opened and what I am now seeing is a little disturbing.

The point is that it doesn’t matter how much water you actually use, the Code judges everything by Mr and Mrs Average, Joe and Joanna public, and according to water company statistics, they use about 130lts per day each. They break it down thus:

• They each flush the loo 4.8 times a day (c 20lts)
• They wash their hands or brush their teeth for 40 seconds a day (10lts)
• They use about 25 lts at the kitchen sink each day
• Their washing machines account for 16lts per day each (49 lts per cycle, and J&J each use it once every three days)
• Their dishwasher uses another 4lts per day each
• And then there’s showering and bathing. It gets complex here because Jo likes showers and Joanna likes baths, but overall it evens out and tends to account for 50lts per day each
• I make that 125lts a day each. Give or take 5 lts, that’s it.
• This might have been better with a pie chart, but it wouldn’t have been so much fun.

The standards set out in the Code would seem to indicate implicitly that this amount of water usage (i.e. 130lts per person per day) is unsustainable — i.e. wicked and to be strongly discouraged. The challenge set out in the Code is not to change the washing or bathing habits of Joe and Joanna, but rather to engineer in solutions which enable them to live exactly as they do now whilst consuming much less piped water.

Welcome to the world of water-efficient appliances. Low flush toilets help matters, and that without any apparent pain. If you can specify aerated taps on the kitchen sink and a water-efficient washing machine you can rapidly reduce that notional figure of 130 lts per person per day down to just over 100 lts per day. So far so good. Just as with energy efficiency measures, the first steps are easy and cost effective. So you can get to Code Level 4 without too much hassle.

It’s that 80 litres a day at Level 5 and 6 which is the problem. You see there just don’t exist any water efficient products that can get Joe and Joanna’s usage down to such a low notional figure. That’s where my spreadsheet came in: I was tinkering with all the very low water usage appliances out there and I still couldn’t get below 102 lts per person per day. This includes:

• dual flush toilets that work on 4.5 lts full and 3 lts half flush
• showers that use just 7 lts per minute
• aerated kitchen taps using 2.5 lts per minute
• washing machines using 35 lts per cycle rather than 49 lts

So how do you go that extra mile, or in this case 22 lts, and get the notional consumption down to Code Level 5 and 6 requirements? The answer the Code is steering us towards is, of course, recycling, either via rainwater harvesting or grey water systems. But even by taking this big leap, you are not guaranteed a result. This is because Joe and Joanna, even with the most water efficient appliances installed in their home, are still using more than 80 lts a day before so much as a loo is flushed. Grey water systems, which reuse bath, shower and basin water for toilet flushing purposes, aren’t going to get you under the 80lts per person per day figure on their own. Rainwater harvesting systems can be set up to run washing machines as well as flush toilets and so in theory could get your notional usage figure down below 80lts per person per day, but only if they operate at near 100% efficiency which is unlikely over the course of a year — in prolonged periods without rain, the storage tanks empty and the systems switch over to tap water.

The conclusion has to be that this 80lts per person per day figure is really at the limits of what is technically possible at the moment. It may well be that you have to fit both a grey water and a rainwater recycling system to meet the target. Grey water systems seem to cost anywhere between £1500 and £2000, rainwater rather more. That’s not a problem if you are building exemplar homes for demonstration purposes but remember we are aiming this at every new home built after 2016. That is a phenomenal challenge and a phenomenal expense to be borne.

There are some further strange anomalies in how the guidance has been put together. If you specify a bidet, you take an instant 5lt per person per day penalty; if you specify a water softener, you take a 12.5lt per person per day penalty. It’s hard to see how anyone will be able to fit these into a new home and still make Code Level 6. On the other hand, if you specify a swimming pool or an outdoor whirlpool bath, there is no penalty at all!

Rather than tinkering about with how we distribute water around the home, wouldn’t it be a lot easier and a lot less hassle just to charge the correct price for tap water in the first place? All new homes in England have metered supplies now in any event, so we already have a perfectly responsive mechanism in place for restricting water usage. As has been pointed out elsewhere, there are many parts of the country where water shortage is not and is never likely to be an issue. Shouldn’t the water restriction measures in the Code reflect this?

Underlying this is a debate very similar to the one raging over renewable energy. The government seems to be keen to promote onsite renewable energy (also via the Code) despite all the evidence being that it is much cheaper and more efficient to green the National Grid. With water, there is no national water grid but coincidentally, there is an article in this week’s Building by David Lush arguing that there should be. The main argument used against building a national water distribution system is cost and Lush quotes an Environment Agency consultation paper suggesting that it would cost between £9billion and £15billion. That may sound like a lot, but £2,500 spent on water reduction measures in every house after 2016 would cost £625million a year and would end up surpassing the cost of building a national water grid after 20 years. Neither option is exactly cheap. It may be that we should do both: I am not against recycling grey water or rainwater, but I do worry about the Code’s insistence that we must keep putting more and more stuff into our homes in order to make them sustainable. Stuff not only costs, but it breaks down, it needs servicing. Its all very well enthusiasts fitting stuff, but 250,000 homes a year? Has anyone seriously thought through the implications?