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About the SEC |
| Climate change, carbon emissions and sustainable technology have become major factors in building design and specification. Government targets to reduce industrial carbon emissions by 20% before the year 2020 has led to new thinking in the installation of energy-efficient building systems. |
| The heating, cooling and electrical demand of a building is responsible for 90% of its environmental impact in terms of carbon emissions, so no matter what energy source is utilized to power, heat and cool them, it makes sense to do it as efficiently as possible. The main challenge here is not developing new technologies – there are plenty to choose from already – but getting manufacturers, architects and governments to respond is the task ahead. |
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| Mike Lamb, the Managing Director of Warmafloor, one of the UK’s major manufacturers of heating and cooling piping systems, has taken up the challenge. Mike has been in the business more than 20 years and his company’s growth has led to the requirement to build a new larger head office, factory and training centre. In Mike’s words, “This presented us with an opportunity to demonstrate what could be achieved with existing know-how and technologies, not only to meet government targets for 20% reduction in carbon emissions, but to exceed them by a significant margin.” He believed a reduction of at least 60% was not out of the question! |
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| Starting from a ‘greenfield’ site and utilizing existing conventional technology, Mike was able to plan every detail of environmental compatibility and energy efficiency from square one. His experience told him that commercial and public buildings in the UK call for cooling rather than heating for 80% of the time. He recognized that his perfect starting point for building temperature control was ground water at 11 to 12°C. The initial installation was therefore to bury 4 kilometres of 50mm diameter polyethylene pipes under the car parking area in circulation loops. |
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The ground-sourced water at a constant temperature between 11 and 12°C could then be connected via heat pumps to supply 20 mm polybutylene heating and cooling pipes encased in concrete floor slabs. This construction provides a stable thermal mass at the heart of the building. With the base load efficiently provided, additional planning and design was focused on providing top-up heating or cooling required by changes in the building's occupancy loads or variance in weather conditions. A 15 mm diameter polybutylene piping system clipped to the back of aluminium ceiling panels would – like the floor construction – provides an ‘as required’ additional heating or cooling source, with energy supplied by the ground water heat pump. |
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| To add to the controllability of the system, it was decided to install a third heating / cooling component for meeting rooms which have south-facing windows, and hence have a high solar gain. Into the corners of these rooms, linear fan-powered fresh air convector units were installed where the air is heated or cooled by an air handling unit which draws its energy from the ground water circuit. |
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| The three ground water-fed piping systems (floor circuits, ceiling circuits, and air handling unit) were integrated to work independently or in unison to provide the optimum comfort in any part of the building. The heat pump system is sized to meet 100% of the demand for most of the year, with a small high efficiency gas powered condensing boiler installed to kick in for thermal top-up on the very coldest days. |
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| A further essential element of heating / cooling efficiency is the building’s insulation capacity. To optimize this on a cost performance basis, the walls and roof cladding for the building specified a polyurethane resin (PUR) insulation barrier to achieve a high insulation value. Decorative over-cladding to enhance the external appearance of the building was also included in the design. |
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| Having dealt with temperature control in the building, what could be achieved in terms of low energy hot and cold water supply? The installation of commercially sized solar hot water heaters were specified to provide the baseload for hot water demand within the core of the building, serving the toilets and showers. Should there be a shortfall from the solar panel supply, a direct acting electrical unit was also specified. |
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| An additional environmental consideration was the efficient use of mains water supply, and hence the new Warmafloor building was designed to utilize the potential of rainwater harvesting. The entire roof area was designed to maximize the collection of rainwater to feed a single 12,000 litre storage tank sited below ground. This water could then be utilized for WC flushing, company vehicle washing and other ‘grey’ water applications. |
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| As a contribution to carbon offsetting, more than 200 shrubs and trees were planted around the site with an irrigation system installed to be fed from the harvested rainwater. Silver birch trees have been planted outside south-facing offices so as to provide solar shading in the summer, yet allow maximum natural daylight in the winter months. |
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Glazing for the site was specified as Pilkington ‘K’ glass and on the southerly facing windows, solar film was applied, which has a solar reflectance of 52%, but an interior visible light reflectance of 58%. |
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| High efficiency light fittings have been installed where possible, with movement sensors in toilets and certain other rooms ensuring that lights automatically switch off when not needed. Three reflecting tubes were also specified to bounce maximum natural day light through the roof to the first floor training area, and to reduce the demand for electrical lighting still further. |
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| The installation of a wind turbine on the roof of the building to offset mains electricity usage has been considered but temporarily shelved. The preferred technology in this respect is still not commercially /economically available. In the foreseeable future, Mike feels that photo-voltaic solar systems will become a feasible option, which have significant benefits over wind power, so for the time being, Mike is adopting a 'wait-and-see' policy. |
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| The Warmafloor building, totaling 27,000 m3 of internal volume on a site of 3,350 m2 was completed at the end of 2006. The initial conclusions from the first 9 months of operation indicate that, compared with conventional energy services, the installed sustainable technologies will reduce energy consumption by at least 60%. Mike claims that this will show a saving of 8kg of CO2 per m3 per year – some 15,000 kg per year for the complete building. Warmafloor is working with the Building Services Research and Information Association (BSRIA) to monitor energy and environmental efficiency of the building over a period of time. |
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| Mike Lamb believed in, and invested in, an integrated sustainable building energy solution to reduce energy demand and save money in his own building. In the first few months Mike realised that visiting building services specifiers and architects were excited that such a common sense approach actually works! By popular demand he has converted a part of the warehouse area into the Sustainable Energy Centre to showcase how a number of proven, affordable, energy-efficient solutions can be integrated to provide an attractive, modern, sustainable work place. It should be possible for all buildings to be this sustainable, Warmafloor is simply showing the way. As more specifiers adopt the solutions showcased in the Sustainable Energy Centre, Mike may end up having a significant impact on the many of the county's future buildings. |
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