Cancun: practical examples for EE in buildings
Cancun, 06.12.2010 - REEEP International Secretariat
Buildings are responsible for 40% of final energy use in most countries. The current building stock will be with us for generations to come, and at the same time, by 2050 the world population is projected to grow by 2.7 billion with a related demand for new built space. Clearly, energy-efficient building design, construction and retrofits are all vital in meeting the climate change challenge.
Against this background, the REEEP-EEC organised side event to the COP16 proceedings in Cancun ‘Energy-efficient buildings: the no-brainer for mitigating climate change’ brought together key architects and developers to offer concrete ideas for taking action.
Peter Boelsterli, the head of the architecture faculty at the Berne University of Applied Sciences in Switzerland, runs a REEEP-sponsored training programme targeting architects and building professionals in China. That country accounts for half of the world’s new building and its startling rate of growth presents challenging conditions for consideration of energy efficiency. Architects there are expected to design significantly greater square footage than their counterparts in Europe or America so quality is at risk.
He spoke of the need for China to learn from mistakes made in Europe in our move to greater energy efficiency, as well as guarding the important local knowledge gathered over a thousand years to create climate adapted buildings, which could so easily be lost in the rush to redevelop. Most importantly, he stressed the need for an integrated approach considering technical, social and economic factors, and ‘mutual learning’ through interaction between all actors – business, public sector, universities and NGOs.
Robert Allender, the Managing Director of Energy Resources Management, a Hong Kong-based energy efficiency consultancy, urged participants to think not of ‘saving energy’ but rather ‘not wasting energy’. He gave examples of Asian approaches including Korea’s aim to become the first country in the world with a universal smart grid, which is is projected to save 40m tons of CO2 per year in efficiency gains. A roadmap has been developed with roll-out planned by 2030. He also talked about how data is being used to drive emissions reduction in India and Singapore, with the latter having a Green Mark system for buildings that he regards as the best in the world. It is not a check-box system, but directly performance related, with decreasing targets for energy use per square metre to achieve a silver, gold, gold-plus or platinum standard.
Giving a host country perspective on low-energy building, Ing. Fernando Mayagoitia Witrón, Leader of the Innovating Project and Sustainable Development in Urbi, described a pilot project for net zero buildings in Cancun. His company has built a block of 15 apartments as part of a larger master-planned residential scheme for low income families. It achieves its overall net zero rating through 55% savings due to energy efficiency measures and the remaining 45% contributed though renewable energy - a grid connected solar PV farm next to the building.
The energy efficiency savings come mainly from design features that mean the building doesn’t need air conditioning, but still maintains an internal temperature of less than 30 degrees Celsius during the hottest months. This includes both the hi-tech – deployment of nanotechnology in a modified graphite roof covering that reduces the amount of the sun’s heat penetrating the building – and the natural – carefully considered tree planting to provide shade where it is most needed. Although the cost of the block was 29% greater than a similarly-sized basic building, it was still less than USD 19,000 per apartment. Ing. Mayagoitia expects that premium to reduce if these buildings are rolled out on a larger scale and, crucially, the net zero version is expected to save 30 tons of CO2 per year.