Marianne Suhr: Going solar

My neighbours, Alex and Martine, are undertaking a massive renovation project on their unlisted Georgian house. They are adding photovoltaic cells to produce electricity to the rear roof slopes and solar thermal panels for heating water.

Solar photovoltaic panels (PV) use energy from the sun to create electricity. PV requires only daylight – not direct sunlight – to generate electricity. The PV cell consists of one or two layers of a semi conducting material, usually silicon. When light shines on the cell it creates an electric field across the layers, causing electricity to flow. PV arrays now come in a variety of shapes and colours, ranging from grey solar tiles that look like roof tiles, to panels and transparent cells that you can use on conservatories and glass to provide shading as well as electricity. Alex and Martine are fitting these to the south-facing slope of their roof to catch as much light as possible.

Solar thermal panels use energy from the sun to heat water, working alongside a conventional boiler. It is claimed that these panels can provide almost all of your hot water during the summer months and about 50% year round. For domestic hot water there are three main components: solar panels, a heat transfer system, and a hot water cylinder. Solar panels – or collectors – are fitted to your roof to collect heat from the sun’s radiation. The heat transfer system uses the collected heat to warm up water. A hot water cylinder stores the hot water that is heated during the day and supplies it for use later. These are a great way of heating a swimming pool.

Making plans

• If you’re installing a renewable energy system, make sure it comes under the Microgeneration Certification Scheme (MCS), and only use MCS-approved installers (microgenerationcertification.org).
• Check whether your system will qualify for the Feed in Tariff Scheme which started in April 2010. Through this scheme the government will actually pay you for generating renewable power. They will also pay a bonus for any surplus energy that is sold back to the national grid. See the Renewable Energy Association’s website for further information (r-e-a.net).
• If your house is listed, you will have to apply for listed building consent to carry out these alterations. Permission will depend on how prominent the additions will be and how much impact they will have on the historic fabric of the building.

Find out more about how to 'future-proof' your home...
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WORDS & PHOTOGRAPHS MARIANNE SUHR
Featured in the June 2010 issue of Period Living