AT Home with Sarah Beeny - December 2011 - (Page 222)
10 things you may
not know about solar panels
We’ve all seen them, but do we know much about these eco-friendly energy makers?
Solar cell technology started way back in the 1800s by the French physicist Antoine–César Becquerel. While experimenting with a solid electrode that was dipped in electrolyte solution, he was able to see a photovoltaic (PV) effect. He even saw a voltage develop when the sunlight fell on the electrode. The earliest solar cells and panels that were created were extremely inefﬁcient and the energy conversion received from the sun stood under 1%. In 1954, three American researchers, Gerald Pearson, Calvin S. Fuller and Daryl Chapin were able to develop a new solar panel that had the efﬁciency level of 6% when it came into contact with direct sunlight.
Photovoltaic (PV) cells are made from layers of semiconducting material, usually silicon. When light shines on the cell it creates an electric eld across the layers. The stronger the sunshine, the more electricity is produced. Groups of cells are put together in panels or modules that can be mounted on your roof. The power of a PV cell is measured in kilowatt peak (kWp). That’s the rate at which it generates energy at peak performance in full direct sunlight during the summer. PV cells come in a variety of shapes and sizes. Most PV systems are made up of panels that t on top of an existing roof, but you can also choose to t solar tiles.
‘Energy e ciency should be top of the priority list for all home improvement work which is carried out these days.’
The country that has the most solar panels in the world is gloomy-skied Germany. A global leader in electricity generated through solar panels, it produces almost half of the world’s total solar electricity. Fifteen of the 20 biggest solar panel plants in the world are in Germany, in line with the decision by the German HOT CASH: government to phase out SOLAR PANELS all of its nuclear power PAY FOR plants by 2020. Germany’s THEMSELVES photovoltaic solar BY REDUCING electricity now forms BILLS almost 10-15% of the total electricity production in this country at peak times. Prices of PV systems have decreased more than 50% in the last ﬁve years. The German government aims to have 66GW of installed solar PV capability by 2030.
Solar electricity systems, also known as solar photovoltaics (PV), capture the sun’s energy using photovoltaic cells. These cells don’t actually need direct sunlight to work – they can still generate some electricity on a cloudy day. The cells convert the sunlight into electricity, which can be used to run appliances. An average system is 2.9 kWp and will cost around £11,700 (including VAT at 5%). Most domestic PV systems cost around £3,500 to £4,500 per kWp installed, but shop around because costs do vary between installers. Panels built into a roof may look neater, but they cost more than those that sit on top.
Solar PV doesn’t need much maintenance once they are ﬁtted, apart from keeping the panels clean and making sure trees don’t overshadow them. The panels should last 25 years, but the inverter is likely to need replacing during this period, at a cost of around £1,000. >
222 | DECEMBER 2011
WORDS: GEORGINA MARIC | PHOTOGRAPHS: GETTY IMAGES
Table of Contents for the Digital Edition of AT Home with Sarah Beeny - December 2011
HELLO FROM SARAH
MAKE IT A DATE
PASTE IT UP
TO LET OR NOT TO LET?
KEYS TO THE DOOR
QUEEN OF THE CASTLE
TRICKS OF THE TRADE
BEST OF THE BRIGHTS
STORE IN STYLE
SHAKE IT UP!
NIGHT ON THE TILES
THE TEMPERATURE’S RISING
BURN BABY BURN
KEEP IT IN
DON’T BLAME THE TOOLS
AT Home with Sarah Beeny - December 2011