British cleantech firms partner on ‘carbon negative’ building projects

Louise Bateman

4th March 2010

Two British clean technology firms have joined forces to deliver commercially viable, large-scale ‘carbon-negative’ buildings.

ModCell has devised a renewable, carbon capturing building system that can reduce heat costs by 85 per cent and is behind the ‘BaleHaus @ Bath’ sustainable home project. The company has teamed up with PassivEnergy, which is behind an energy management system that uses sensors to control heating, hot water and electrical equipment, further reducing energy usage.

The two companies, which finalised the agreement on a recent investment mission to the US, aim to work together on homes, commercial developments and public sector schemes and today announced their first project together, a primary school in Cheshire. The project is part of the Government’s Building Schools for the Future (BSF) programme.

According to a spokesperson for PassivEnergy, the company will install its energy management system in the existing school buildings at Kingsmead Primary School as part of a retrofit, while the ModCell carbon negative building system will be used in a new early years community centre being built on the school site.

ModCell system uses straw bales and hemp

The ModCell system uses straw bales and hemp – natural carbon negative materials that can be sourced locally – in prefabricated walls, creating super-insulated low energy buildings. The materials are carbon negative because they capture CO2 and release oxygen during their growth and then lock the carbon into the fabric of the building they are used to construct. The effect, according to ModCell director Craig White, is a commercially viable construction that reduces carbon emissions by 60 per cent and heating costs by 85 per cent.

The PassivEnergy system works using sensors and actuators that connect to a building’s heating, hot water and electrical appliances and manages them via an online account. An ‘Adaptive Occupancy Control’ function allows the system to further optimise energy use, which ‘learns’ how a building’s energy is being used and automatically adjusts and controls energy consumption accordingly.

ModCell and PassivEnergy will partner on 'BaleOffice'

“The combination of our two companies’ technologies makes for an extremely compelling proposition,” said White, who told GreenWise the partners would combine their two technologies on all future ModCell projects, including a housing development of 20 homes in Leeds and a ‘BaleOffice’ development in Chippenham, Wiltshire.

The Kingsmead Primary school project is scheduled for completion in September 2010 and, according to White, the partners are aiming to win further BSF contracts, both retrofit and new builds.

“BSF provides an enormous market opportunity for ModCell and PassivSystems,” he explained.

Colin Calder, ceo of PassivSystems, added: “Adding PassivEnergy to the ModCell® Renewable Schools’ super efficient building system will make these first schools a blueprint for any further schools intent on lowering carbon emissions.”

ModCell’s BaleHaus @ Bath, which was funded by the Technology Strategy Board, was a test-bed for the performance of sustainable building materials in mainstream construction. The house can be built in two and half days using the ModCell building system and its high-energy efficiency credentials means it can compete with standard Code Level 4 for Sustainable Homes builds, acoording to White.