Delivering low carbon buildings in practice

Two recent articles in Building caused quite a stir when they reported the Carbon Trust’s research into the new wave of low carbon buildings. Five years were spent following more than 30 major projects from design through to construction and in use. This revealed an inconvenient truth - low carbon buildings simply aren’t performing as promised.

In a little under 10 years, all new buildings will supposedly be “zero-carbon”. But our analysis has highlighted the glaring gap between design and actual energy consumption. Even many of the “flagship” projects featured in the Low Carbon Buildings Programme have struggled to better “good practice” benchmarks for carbon emissions defined 20 years ago. Astonishingly, some of these buildings are using as much as five times more energy than their designers originally estimated.

There’s no lack of commitment or enthusiasm to deliver low carbon buildings, so why isn’t this being achieved in practice?

All too often, designers focus on regulatory compliance rather than delivering a building with low running costs. Complexity is often the enemy of good performance. One high-profile public building with four different renewable and backup heating systems was so difficult to control that the gas boilers seemed to be running instead of the heat pumps for most of the year.

On top of this, contractors tend to hand over the keys and walk away, rather than stay involved during an extended handover.

The consequences of all this can be costly. In one case, poor commissioning of a building’s systems added £10/m2 to the client’s energy bill in the first year.
The government needs to reaffirm its commitment to decarbonising the UK’s buildings and we need to change the way our buildings are designed, delivered and operated. Here’s how.

All too often, designers focus on regulatory compliance rather than delivering a building with low running costs

First, we need to understand how our buildings are really performing to create a true market in low carbon buildings. The Carbon Trust supports the UK Green Building Council and others in calling for the roll-out of display energy certificates (DECs) across the UK’s non-domestic buildings to reveal the best and worst performers.

With DECs as a common language, clients could confidently specify the energy performance they want - and hold designers to account for achieving it. As DECs are prominently displayed, occupiers of gas-guzzling buildings would face a risk to their reputation. Investors could finally quantify the elusive link between sustainability and value - and so mobilise the capital needed to de-carbonise new and existing buildings. And only with real data could the government use taxation as an effective lever to cut carbon by penalising the worst offenders.

Second, this fiercely competitive industry needs forums in which to share and learn tough lessons. Carbon Buzz is one new initiative that pools data and compares design and actual energy consumption. It’s already providing valuable insights, but it needs to be at a much greater scale to have real impact.

But most important, we need new ways of working that align the interests of landlords, tenants, designers and investors in the actual energy performance of their buildings. One potential model is a unique partnership between the Carbon Trust, investors Threadneedle and developer Stanhope. Low Carbon Workplace requires occupiers to commit to eco-friendly operation, and provides them with ongoing support to help them to achieve certification and recognition to the new low carbon workplace standard.Two years ago our report - Building the Future, Today - showed how by 2050 we could cut the carbon from the UK’s non-domestic buildings by 80%. There are success stories, but if we are ever to realise the potential benefits of more efficient buildings, we will need to see changes throughout the sector.

Richard Guy is senior strategy and operations manager at the Carbon Trust

This article was originally published under the headline ‘Reaching new lows’