Reading and renewable energy are being combined in the U.K.: The British Library in London has commissioned the largest solar heat project in the country.

The 950 solar collectors will be installed across 712.5 m² of roof space by solar technology company Naked Energy. The project is expected to reduce the building’s carbon dioxide emissions by 55 tons annually and to deliver 216 MWh of energy per year. The company’s Virtu collectors merge solar photovoltaic and thermal (PVT) photovoltaic technology to generate both electricity and heat from a single unit.

Source: Naked Energy

Photovoltaic cells on the fins of the PVT tubes convert 20% of the sunlight to DC electricity. Each set of five PVT tubes is equipped with a micro-inverter, which converts the DC electricity to AC electricity, to be used throughout the building. Most of the remaining 80% of the sun’s energy is converted to heat and stored in a 15 m³ tank which serves as a thermal battery, generating solar heat during the day for use later in the evening or on the following morning.

The Virtu collectors save up to four times the amount of carbon as standard solar photovoltaic panels, representing an advance in decarbonizing heat in various end uses. The hybrid solar units capture the sun’s heat energy up to 75° C and heat water up to 120° C. The technology will supply sanitary hot water and space heating for the British Library to the benefit of staff and visitors.

The installation will also be used to help to maintain the precise temperature and humidity conditions needed to preserve the national collection cared for by the British Library, which exceeds 170 million items.