Figures released by the Department of Energy and Climate Change (DECC) suggest that approximately 40% of the UK’s non-transport energy consumption is a direct result of large space heating, with much of this attributed to offices, factories and warehouse facilities.
With increased pressure on businesses to become more proficient both financially and environmentally, many companies are looking towards highly efficient, holistic heating solutions which can be combined with established renewable technologies as part of their sustainable building strategy.
Solar air heating is one such technology which has become more prominent over the last 30 years, thanks to its effective integration into both new and existing buildings, delivering significant reductions in heating costs and energy usage.
The SolarWall® technology was the world’s first Transpired Solar Collector when it was developed back in the 1980’s by Canadian company Conserval Engineering Inc. and has revolutionised the solar air heating industry.
The SolarWall® Transpired Solar Collector is an open-loop, active, ambient air-heating solar collector, which harnesses the sun’s energy to heat fresh, outdoor air for buildings. With no moving parts, the SolarWall® collector provides a truly renewable heat source and with solar collection efficiencies as high as 80% the system offers one of the fastest return on investments of any solar technology currently available, delivering proven payback periods as low as three years.
Installed as an additional skin to a buildings southerly elevation(s), SolarWall® consists of a pre-coated steel or aluminium collector with thousands of carefully engineered perforations spread across its surface.
As sunlight strikes the surface of the SolarWall® (in the form of visible and non-visible solar radiation) the energy is absorbed, heating its external surface. In turn, by means of conduction, the fine layer of air which lines the outside face of the collector is heated, creating a film of warm air known as the thermal boundary layer.
This heated boundary layer is carefully drawn through the perforations within the surface of the collector into a uniquely designed air cavity that is created between the SolarWall® collector and the buildings original elevation, before the heat can escape by convection, or is lost to external wind.
From the air cavity, the fresh, solar heated air can then be introduced directly into the building as make-up / ventilation air for industrial applications, or ducted into a centralised HVAC unit for commercial and residential applications, where it can be used as a pre-heater to the building’s main heating system.
The SolarWall® Transpired Solar Collector is utilised in over 35 countries across 6 continents and has a proven track record of delivering significant savings in energy consumption and carbon emissions in applications ranging from standard space and ventilation air heating to make up air heating and process drying.
Global Independent Testing
During its development, the SolarWall® Transpired Solar Collector was extensively tested and refined at the Exova (formerly Bodycote) National Solar Test Facility, Ontario, Canada and is one of only a few solar air heating technologies currently available which has been tested to a recognised test standard, Canadian Standards Association (CSA F378) – 1987, updated September 2011;
F378.1 – Glazed and unglazed liquid heating solar collectors
F378.2 – Air heating solar collectors
In 1994 the technology was recognised as one of the 100 most important technological innovations in the U.S., and was rated in the top 2% of energy inventions by the U.S. Department of Energy’s prestigious R&D 100 award.
As well as testing throughout the U.S. and Canada, the performance of the SolarWall® Transpired Solar Collector has also undergone independent monitoring here in the UK by BSRIA, delivering proven reductions of up to 50% in a buildings heating requirement. The system has also been independently thermally modelled by Battle McCarthy Consulting Engineers & Landscape Architects, highlighting that the technology can provide up to 20% of a buildings total energy requirement, in line with stringent targets set by many local authorities.
The RETScreen® International Solar Air Heating Software package, developed by Natural Resources Canada (NRCan) has become the standard global modelling software for calculating the system performance of the SolarWall® technology.
Empirical data obtained from independent testing at the National Solar Test Facility, along with several active field trials, enabled NRCan to develop the RETScreen® Solar Air Heating software package of which v3.1 is specific to the SolarWall® technology. This software package contains all of the SolarWall® performance data pre-loaded and is combined with a NASA weather database, allowing a comprehensive assessment of SolarWall® performance anywhere in the world.
SBEM (Simplified Building Energy Model)
The Simplified Building Energy Model (SBEM) software, developed by BRE, (on behalf of the Department for Communities and Local Government (DCLG) – responsible for the Building Regulations), now has the capability to analyse the performance of the SolarWall® Transpired Solar Collector, allowing funders, designers and building owners to witness firsthand the significant benefits that the SolarWall® system delivers.
Developed in order to accommodate the changes to Part L of the Building Regulations in 2010, the most recent version of the SBEM software is capable of directly analysing the improvement in building energy performance and subsequent EPC rating than can be achieved by incorporating the technology into the building design helping to enhance the asset value, yield and running costs of the building. The technology also has the potential to lower carbon tax as the requirements to reduce CO2 emissions increases.
What Jaguar Land Rover say about SolarWall®
More than 80 construction industry VIPs attended a special ‘SolarWall® in Action’ event at the Jaguar Land Rover Training Academy in Gaydon, Warwickshire. Guests at the event, (which included representatives from The Welsh Assembly, Costain, Kier, B&Q, ASDA and Focus DIY) were able to see first hand how SolarWall®, has helped the refurbished building to save more than 80,000 kWh per year with an associated reduction in CO2 emissions of 19 tonnes. The SolarWall® Transpired Solar Collector Continue Reading »