Manufacturers would like the green dream to become a reality — but are disturbed that attitudes and concerns with capital cost are preventing that happening.
Zero-carbon buildings are achievable; however, a lot of current thinking has to change before they become more than the green dream of environmental organisations — that is the view of Paul Wenden, the current president of FETA (the Federation of Environmental Trade Associations).
He explains that although current building-services products will significantly help designers achieve zero-carbon emissions, the design culture of the buildings themselves has to adapt if we are to get anywhere near zero emissions. One obvious bit of new thinking would be to reduce air leakages, possibly by up to 50%, which is being considered and implemented in some overseas markets.
The effect of air pressure and differences on moisture movement is understood by design and construction professionals, but sometimes they are compromised in the physical construction itself. Sealing air leaks in the shells of buildings reduces energy costs, allows for improved environmental control, and minimises the amount of outdoor air needed to maintain a slight positive indoor air pressure.
But that is only part of the bigger picture, HEVAC members are already innovative — creating products that are ground breaking, meeting customer demands and generally developing greener solutions for customers. If only these products were being used more widely, the dream of zero-rated buildings might take a leap forward.
‘As energy prices continue to increase,’ says Geoff Lockwood from EBM Papst. ‘end users will look to recoup costs in the longer term with energy-saving products, but these generally cost more money. Our fans will meet the current regulations, and even future legislation, but in some ways we do not need more legislation to control carbon emissions, we need legislation to change people’s minds.’
This is a view that Gerry Stapley of Eaton-Williams agrees with; ‘Buildings are never going to be zero rated until the Government enforces some energy-saving standards, and these have to become law before anything will change. With competitive tendering and PFI projects driving prices lower and lower, contractors and designers are always looking for the cheaper alternative. This short-term saving often overrides purchasing decisions on energy efficient products that are currently available; unless contractors see an immediate return on investment it makes it difficult to look at the future.’
One example Gerry Stapley highlights is heat recovery. Products with a counter-flow heat exchanger between the inbound and outbound air flow provide fresh air and improved climate control, while also saving energy by reducing the heating (or cooling) requirements. Installing heat exchangers provides obvious long-term energy-saving advantages in many buildings. However, while they are often on the original specifications of a new-build project, by the time the successful bidder looks to save money, short-term cost savings take priority, and heat exchangers often end up being the target.
Another failing for the green dream is that it is only through research and development that new products will emerge. However, as income has plunged, R&D funding has taken a pounding. Many manufacturers have no choice but to slash their budgets and daily operating costs. This means that longer-term experimentation and discovery (something the Government is asking for us to do) is now in danger.
Anther way to help to reduce a building’s carbon footprint is, where appropriate, to do away with mechanical ventilation and use natural ventilation. This approach allows buildings to breathe properly and reduce their overall moisture content, making the space easier to heat and cool. Tesco proved that zero carbon buildings can be built. Some argue that this was solely because the client was the driving force for the project, creating a great deal of positive publicity.
Tesco opened its first zero-carbon supermarket in Ramsey, Cambridgeshire. The new store aims to be a carbon zero business by 2050. It uses renewable sources for heating and rainwater for flushing toilets and for the car wash. The supermarket has been designed to be energy efficient. It is constructed from sustainable timber, with skylights to allow in natural light but not heat. Vents control a natural airflow to reduce energy requirements.
Paul Wenden concludes that it is now possible to build a zero-carbon building, but that without some fundamental changes in thinking, particularly from building owners, the green ideal will remain where it has floundered for many years — a dream in the minds of environmentalists.