Structural changes

There are many technical challenges and opportunities ahead as sustainability in the built environment becomes a major economic force in relation to both building construction and energy supply. Climate change, the depletion of fossil fuel energy sources and the security of future energy supplies are becoming a major concern for all countries. Materials and water are also becoming short in supply. All these issues are a clear indication that we are living in unsustainable ways.

China is developing at a rapid pace and its rate of building construction is unprecedented, generally with little attention given to the impact that the construction and operation of these building will have on the environment, both locally and from a global perspective. The construction and operation of buildings now accounts for roughly 50 percent of the world's energy, timber and water consumption, producing mountains of waste and eating into agricultural land.

The energy demand to heat, cool and light buildings in China is now at a level where it is constraining economic development. The environments created in and around buildings are also suffering from pollution and heat gains. However, buildings need not consume so much energy and can produce better environments for people.

Projects carried out by the Welsh School of Architecture in collaboration with Chinese universities in Xi'an, Tianjin and Shanghai have demonstrated that considerable energy savings can be made relatively easily though the application of simple design solutions for insulation, solar control, air leakage and better management of heating and air conditioning systems. Further improvements can be achieved through the application of innovative environmental design methods, looking to the UK and Europe for examples. It is time for China to seriously reconsider its approach to the built environment and in particular, how it can integrate sustainability into its "fast track" developments.

Since the energy crises of the 1970s, Europe has been developing buildings that are increasingly more sustainable. These included the control of solar heat and shading design to make use of the sun's heat in winter and to minimize cooling needs in summer, the use of daylight and natural ventilation, and the use of thermal mass to provide thermal stability.

These themes continue to be developed through a new generation of sustainable buildings with innovative ways of heating and cooling using ground thermal storage for "free" heating and cooling, chilled surface cooling and "smart'" environmentally responsive facades.

The UK government has set a target for all new houses to be "zero carbon" by 2016, and in some regions of the UK, for example Wales, the regional government has set a target for all new buildings to be zero carbon by 2011. This implies that in the near future there will be even more of a focus on low-energy design, as well as the use of renewable energy systems to provide the balance of energy needs from non-fossil fuel sources. These renewable energy systems can be building integrated, they can be community based or centralized grid-based systems, using, for example, solar thermal, photovoltaic electricity, wind and biomass.

China is improving its building regulations, but only a relatively small - estimated at 5 percent - of new buildings are actually constructed to meet the current building regulations. Housing in China is now said to use roughly three times the energy compared to European housing. So the challenge for China is not only to continue to improve its building regulations but also to dramatically increase the rate of compliance.

It is vital that this mandatory top-down approach to improving sustainability is combined with a bottom-up approach as mainstream awareness grows and individuals and organizations are encouraged to take on more responsibility for the environment. In the future, the value of buildings is likely to be affected by their sustainability credentials.

An example of this is the introduction of building rating systems, where buildings have to declare their sustainability credentials. Buildings with low sustainability ratings are likely to prove an investment risk in future and this strengthens the economic drivers for sustainability.

Up to now, we have been largely concerned with reducing the operating energy of buildings. Modern methods of construction (MCC) are now being developed where much of the construction process is carried out off-site, which should result in more efficient use of resources and better quality control. The integration of MMC and sustainability is particularly applicable to China's fast-track construction programs.

China is a country in need of sustainable solutions and with the political will to engage with them. China need not go through the same slow and stuttered learning curve that the West has gone through and it can benefit from examples of best practice. The Welsh School of Architecture at Cardiff University is working in partnership with a number of Chinese universities in the field of sustainable built environments, learning from each other.

China can reduce its building energy demand by its targeted 50 to 65 percent using existing building techniques and available skills, if they are enabled. As its experience and skilled base grows, it can progress to further reductions with more innovative solutions for design and using renewable energy systems. The political will to carry this out must be translated into everyday practice, and this is where the problems lie, and not just in China, but in the construction industry worldwide.

We should emphasize that sustainability is not just about negative factors such as, low energy, zero carbon, reduced waste and less is more. Although these form a part of our future design solutions, the main aim is to create healthy, comfortable, productive places to live and work. Future sustainable lifestyles will create their own vibrant local and global economies that foster supporting social structures and cultural trends. A sustainable future lifestyle should not be perceived as a gloomy, constrained existence but rather it offers us bright and exciting challenges and new opportunities to improve the way we live and work. Most importantly, this future should begin today.

Professor Phillip Jones is chair of Architectural Science and Head of School at the Welsh School of Architecture, Cardiff University in United Kingdom. He can be reached at JonesP@cardiff.ac.uk

(China Daily 01/28/2008 page4)