Built to be green
As E&T discovers, there has been excellent progress in sustainable buildings, but much more is still required.
In Copenhagen in December 2009, representatives from approximately 180 of the world's countries will come together at the United Nations 'Conference of the Parties - COP15' to work out a new international agreement to tackle climate change. The current international agreement, the Kyoto Protocol, will expire in 2012; Copenhagen, in effect, will create its successor.
The built environment is responsible for more than a third of global emissions and so to achieve any carbon targets set it is vital that buildings are green and efficient. Energy efficient itself is self explanatory. The built environment currently consumes a high proportion of energy in western societies - typically around 40 per cent for residential and commercial buildings combined - and produces a correspondingly high proportion of carbon into the atmosphere.
We have to reduce this dramatically over the coming years, possibly by up to 80 per cent. Reducing the amount of energy used and switching to sustainable energy provision are both critical to achieving this.
"Much of the Climate Change Conference in Copenhagen will be focusing on energy and carbon, but it's essential that we don't lose focus on the fact that the design and performance of green buildings - and to an even greater extent sustainable buildings - have to be optimised in terms of many other variables as well," Alan Kell, managing director, Intelligent & Green Systems and co-chair, UK-China Energy Efficiency & Green Buildings Working Group, explains. "For example, the efficient use of water is critical in many parts of the world - especially in large cities and urban conurbations - and the selection and use of sustainable building materials is crucial."
Planning, location and design are clearly important issues for buildings, but ultimately no more so than the engineering and management systems that are essential to optimise the buildings' lifetime performance. This is why engaging the engineering and technology perspective is so important - green buildings cannot just be designed 'creatively', sufficient emphasis must be placed upon the engineering and technology systems.
"This has never been more true than today, as the performance demands on building increase so dramatically," Kell says. "Fortunately, as we move from traditional M&E [Mechanical and Electrical] solutions to more powerful M&E&I systems (through the integration of ICT components), we have solutions available to achieve the required step-change enhancement in performance.
"With their profound ingenuity, engineers have the knowledge, commitment and skills to achieve this improvement in building design, construction and performance but they must ensure that they are engaged and involved early - and with sufficient authority - in the building process."
By international standards buildings in the UK are well designed and constructed, not least due to the professional engineering standards and training provided by institutions such as the IET. "Having said that, however, our buildings do not currently perform to the standards needed to address the critical demand of climate change," Kell adds.
"Government policies, building regulations and standards are changing rapidly to address these needs, providing tremendous challenges and professional opportunities for leading engineers, especially British engineers who are renowned throughout the world for their professionalism, commitment and skills."
Every country in the world is facing a major challenge to improve the design and performance of new buildings, and even more so to improve the energy and sustainability performance of the existing building stock. Kell is adamant that Britain is well positioned to achieve this. "The quality and performance of the best of our new buildings is as good as anything elsewhere in the world," he says.
"Ensuring that this 'best practice' becomes the norm is challenging, but achievable. Engineering solutions to improving the performance of existing buildings are also available, but implementing them in a timely manner will require concerted political, financial and social commitment."
By its very definition, technology is always changing and improving but we just can't afford to wait for new solutions that are just over the horizon. And in practice we don't need to - we already have sufficient engineering and technological solutions to achieve our aims, as has been demonstrated in numerous demonstration and pilot projects. According to Kell, what we now need is to main-stream these solutions as rapidly as possible, under the professional leadership of the engineering community.
"Short-term market subsidies and special support may be required to accelerate the adoption of these new solutions, as they often are during times of rapid transitions, but as global volumes increase the cost of the new engineering solutions will fall rapidly, and the economic imperative will join the environmental as a powerful and irresistible force for change," he says.
At present the options for heating a building are traditional gas or oil fired boilers, onsite renewable technologies such as ground or air source heat pumps, biomass boilers, or by connection to communal or district heat networks. But there is an alternative in the form of building networks, as Michael King, a consultant with the Combined Heating and Power Association (CHPA), explains. "It is my argument that only through the use of heat networks is it possible to deliver low and zero carbon heat to towns and cities at scale.
"Most onsite renewable technologies have difficulty in meeting all of a building's demands for heating, particularly in meeting peak loads," he continues. "They generally have to run as hybrids in parallel with gas or oil boilers. This doubles up on the cost as well as creating difficulty in meeting increasing stringent demands for low and zero carbon under the Code for Sustainable Homes.
"By contrast, heat networks can balance out peak loads of any one individual building by aggregating its demand load with other buildings occupied by different consumer types with different demand profiles. Additionally, it can use a wide variety of energy sources - CHP, biomass, waste heat from industry and power generation, advanced energy-from-waste technologies - to reduce the carbon intensity of heat. Most of these technologies can only be implemented at a scale beyond the individual building."
Most renewable heating technologies are proven technologies. However, it must be recognised that the deployment of any low and zero carbon energy technology is spatially determined. That is the applicability of any technology is determined by the availability of fuel stocks, building density, consumer diversity, presence of anchor loads and energy distribution and transport infrastructure.
Funding is available for sustainable heating projects through a variety of resources, some well established, others in their early days. Capital support programmes such as the Carbon Emissions Reduction Target and Community Energy Saving Programme as well as revenue support programmes such as the Feed-in Tariff, Renewable Obligation Certificates, the Renewable Heat Incentive and the EU Emissions Trading Scheme.
"Alongside these 'carrot' mechanisms there are sticks such as the Carbon Reduction Commitment," adds King. "However, most low and zero carbon technologies have a heavier upfront capital cost. So it remains to be seen how effective these mechanisms are in stimulating uptake."
To learn more about this topic you can attend The IET conference - Green and energy efficient buildings: preparing for the challenges of Copenhagen - that takes place at Savoy Place, London on 2 December.