We run the risk of adding unnecessary costs and bureaucracy to the drive to zero carbon buildings under the current legislative framework. Influential green figure and thinker Pooran Desai argues for an approach to green construction that simplifies short term goals and incorporates broader sustainable principles than just C02 used in heating and powering buildings.

We all know that we must exit this economic downturn in a way which enables us to create a very low carbon future. However, we have tied ourselves in knots with the Code for Sustainable Homes and Zero Carbon, creating confusion and adding unnecessary costs. Now is the time to untie them and create a set of standards and processes which will enable us to deliver both effectively and cost-effectively.

Hold back the Code

Up to Code Level 4 (approximately the old EcoHomes Excellent), the outcomes from an environmental persepective are basically sound though the metrics can be made more straightforward, robust. However, Code Levels 5 and 6 as they are currently written are of dubious environmental value. The industry now generally accepts that forcing ‘net zero carbon’ on-site electricity generation is not helpful. There are other problems. On higher density sites particularly where you can’t collect sufficient rainwater to flush toilets, it forces on-site grey water treatment, often energy and chemical intensive, when even the Centre for Alternative Technology states that conventional sewage treatment is more eco-friendly than on-site grey water recycling. The solutions needed to deliver Code 5 and 6 are not just expensive in capital terms, but may not be kept operational because of high maintenance costs. This means that many homes built to current Code Level 5 and 6 will be less eco-friendly than Code 4.

Then there is the unnecessarily vexed question of Zero Carbon.The line of thinking underpinning recommendations from the UK-GBC’s Zero Carbon Taskforce and the recent Zero Carbon consultation from CLG unfortunately will not result in a workable solution – they are not grounded in practical application. The complexities of defining ‘additionality’ and ‘allowable solutions’ will add bureaucracy, cost and delay, particularly unhelpful as we have an already tangled planning system. Our experience as developers now shows we are spending as much or sometimes more money on reports for planning authorities, Environment Agency, BRE, etc as we are on renewable energy technologies. A Carbon Fund on new housing similarly is not the most efficient way to Zero Carbon, not least because the time the adminstrators, lawyers and consultants have taken out there fees, not much will end up in renewable power generating capacity.

What should the solution be? The UK is committed to delivering an 80% reduction in carbon emissions by 2050 – it is now considered the minimum to avoid catastrophic climate change. How can we achieve this massive reduction? Our starting point must be creating sustainable lifestyles, in which green buildings are one component. Taking this perspective, we see that increasing space heating performance of homes from Code 4 to Code 5 will save say 750 kWh of energy per person per year which, if replacing gas, would amount to about 1% of a person’s carbon footprint, adding to build cost but only saving relatively small amounts on energy bills (arguably with global warming leading to warmer winters we might not even see this benefit).

Transport wins

However reducing car dependence by building places which are walkable and cyclable reduces financial costs and embodied carbon of construction by reducing parking and road infrastructure. Each car avoided saves a household over £2000 per year and perhaps 10% of a person’s carbon footprint. Not insignificantly, by increasing levels of exercise, it will also help tackle the epidemic we have of obesity and diabetes. We are not necessarily talking about car-free communities in all cases but creating places where it is easy for people to get rid of second and third cars in households. How we masterplan, remodel, manage the built environment long term and the lifestyles they determine – from transport to food and waste – will all be important parts of a zero carbon future. Transport is just one example showing how the largest and most cost-effective carbon savings will come from creating whole sustainable lifestyles. Every single building we construct – even small developments - can help contribute to a wider move to creating sustainable lifestyles.

Our experience as developers now shows we are spending as much money on reports for planning authorities, Environment Agency, BRE, etc as we are on renewable energy technologies

Understanding the overall costs and benefits must inform the standards we set for green buildings in order to deliver real overall carbon savings. Reaching Code 4 space heating standards will deliver homes which are super-efficient compared to existing housing stock (around 80% more efficient). When the industry has a reasonable chance of delivering Code 4 space heating performance for instance (which it doesn’t at the moment), we can then, if we choose, raise the minimum standards to get that last little bit of energy saving from the building fabric. But let us not be under any illusions of the size of the savings – it will be small. Get the basics right and tweak later.

BedZED mark two

BedZED has been an inspiration for a lot of what has become called the Zero Carbon homes agenda. However, it is now time to look for direction from a new generation of projects. The BedZED project aimed to generate net zero emissions from on-site generation, but that proved very expensive and ultimately the biomass CHP was not successful technically (with hindsight, even if it had been it is unlikely we could have run it cost-effectively because of its small size). Therefore learning the lessons of BedZED, since 2003, BioRegional have been using Zero Carbon to refer to buildings run on a combination of on- and off-site renewables using fossil fuels only as back-up.

This simple starting point (followed by very hard work on delivery) provides the basis for ‘One Brighton’ being built by BioRegional Quintain in joint venture with Crest Nicholson, with first residents moving in summer 2009. One Brighton builds on the lessons, analysis and extensive monitoring of BedZED. The 172 apartments are being constructed to the original BioRegional Zero Carbon definition by way of a biomass boiler, gas back-up heating, bulk purchase of guaranteed green electricity and support for off-site large scale wind turbines (though the last point should not necessarily be the responsibility of the developer – BioRegional Quintain just choose to do it). We appreciate that buying green electricity, even from the most responsible suppliers such as Good Energy, does not necessarily meet an ‘additionality’ criterion but sends an important market signal. Additionality though is probably a flawed concept as we shall see later. Scoring ‘Excellent’ under BRE EcoHomes, One Brighton, would, with a little tweaking, achieve a respectable, but not headline-grabbing, Level 4 under the Code for Sustainable for Homes.

Our Zero Carbon strategy must be informed by real-life experience– if we are not to continue being led on a merry dance

One Brighton
The One Brighton scheme being developed by BioRegional Quintain

So why I am saying this is the new benchmark? Because it is being constructed within conventional cost parameters, is Zero Carbon and creates a whole sustainable ‘One Planet’ lifestyle from which major carbon savings will arise. This aspect of creating a sustainable lifestyle is critical to achieving the 80% cuts in carbon emissions which we, as a nation, are committed to meeting in the UK by 2050.

The solution to Zero Carbon lies in a recognition that electricity is best considered a pooled resource and that creating a low carbon electricity supply should be led by national energy policy rather than trying too hard to turn buildings, directly or indirectly, into power generators. We need a green grid which we must accelerate through a coherent national renewable energy policy, with the right financial and regulatory measures which can include fixed prices for green electricity production and Renewable Obligation Certificates and fixed prices for green electricity production (there will also be a need for coherent strategy to balance the grid and for ‘smart grid’ initiatives to reduce peak loads). We should also have incentives for renewable heat. However, in all cases, we should aim to create a level playing field for on- or off-site solutions, not artificially drive one solution over the other. Let a practical, economically efficient balance of on- and off-site solutions emerge. Complicating delivery of new homes through ‘Allowable Solutions’ such as insulating buildings in the surrounding areas are an unnecessary complication.

Retrofit direction

We need a separate national policy for things like retrofit and not mix this up with delivering new homes. We already have schemes like CERT and Warmfront which can be boosted through communal central government funds and augmented with approaches such as say removing VAT off energy efficiency products (and perhaps increasing VAT on energy intensive products). Burdening new homes with the complexities and costs of ‘Allowable Solutions’ or indeed ‘Carbon Funds’ will push many development sites deeper into non-viability - particularly brownfield sites which are the most eco-friendly to develop.

As well as keeping it sustainable, there is great value in keeping Zero Carbon simple in order to ensure cost-effective delivery (particular given the ‘downstream’ complexities of the planning system), allow simple cost-effective verification (unless we really do want to spend more on consultants than installing green technologies!) and engage everyone in the process from designers and planners through to construction workers.

Our Zero Carbon strategy must be informed by real-life experience– if we are not to continue being led on a merry dance. We have a responsibility to get it right, as well as a great opportunity here. Let’s not squander it.