- Solar Water Heating Systems 'A certificated course for plumbers' - July 1-3 2002 This unique course is being offered by Filsol Ltd, The Solar Design Company and the Centre for Alternative Technology. One day will cover the 'Shine 21' awareness-raising project developed in co-operation with the Association of Plumbing and Heating Contractors. The second day would cover roof mounting of solar ...www.cat.org.uk