We’ve already shared our findings from our visit to a wind farm at Brechfa forest, and now it’s time to talk about the second of our energy sources, the sun.
We had the map location pinned, but the hedges had sprouted high in spring. Behind bright green leaves, sloping back down a hill, in a field surrounded by sheep was one of Pure Planet’s solar generation sites — Blatchworthy Farm, near Tiverton, in Devon.
It was a relief to find it — eventually — its photo-voltaic panels glinting in the sunshine. Impressive. It’s so quiet and discreet you might miss it.
Blatchworthy Farm is operated by one of our energy suppliers, Lightsource BP. And when you put all its farms together, Lightsource BP generates enough sunshine energy to power one million homes in Britain. They kindly arranged for Pure Planet to visit one of the farms, so we could see what goes on, and get a sense of where our energy comes from.
It was also great to have one of Pure Planet’s Members from our Community join us too: Lenny came up from Cornwall to ask questions, and learn more about how his energy is created.
Left to right: Wanda and Liza from Lightsource BP headquarters, me, Lenny from Pure Planet’s Community, and Jordan and Paul from the Lightsource BP operations team.
Paul and Jordan — two of the Lightsource BP operational team — hosted us, taking us around the site to show us just how they keep their solar panels and the farms operating in all conditions (they look after a dozen or so sites around the South West).
This 10 acre site is approximately 400 metres wide on a north facing slope, with all the cells angled precisely south, towards the sun.
The silicon based cells in the panels convert sunlight into direct current. Each cell array has an inverter which flips this into alternating current to feed into the grid, via a transformer.
A Pyranometer measures the sunlight from which the team can calculate how well the farm is performing. The data provides detailed, localised weather information. It’s much more accurate than they can get from the Met Office.
To ensure consistent performance, data is shared with the team’s pickup truck cab, which provides all the information needed on the farm’s activities; what needs watching and where.
Rows of flat cells facing the sun, boxes of inverters mounted behind the cells. The Pyranometer measuring sunlight.
The cells in the panels have a 25–30 year life span, and sit there, silent under the sky.
Amid this rural tranquillity, generation is all monitored remotely. There are sensors on the panels and inverters. To check on the panels’ efficiency and effectiveness thermal cameras are used to check for hot or cold spots.
DC/AC Inverters lined up. I didn’t ask their favourite rock band.
The sites are secured remotely with CCTV and speakers. As well as ourselves, surprise visitors can include small mammals using gates in the fences, deer ignoring the gates and fences and, at other sites, chickens and even sheep have been known to leap out from behind a panel to catch the unwary in their tracks. Lightsource BP puts a lot of effort into the biodiversity of the sites, to work with local wildlife, from farm animals to birds and bees.
The weather does a good job of washing the cells irregularly. Proper glass cleaning happens three times a year, with a giant tractor mounted hose brush — no squeegee. The grass is kept low to avoid anything covering the cells.
The farm is to have all its panels available to the grid during daylight — but if one fails or falls below par, it has to be fixed within 4 hours. It keeps Jordan and Paul on call and on their toes. What happens when it rains? “We get wet,” they smile.
All the electricity is fed into the grid for distribution — not as some imagine, directly to someone’s home. Once on the grid the power is distributed to whoever needs it at that moment: businesses; schools; hospitals; and, of course, nearby homes in Tiverton.
Pure Planet Members in and around Tiverton benefit from the energy being generated from the sun’s rays on the other side of the hills.
But what happens when the sun isn’t shining? That’s where the grid comes in: it is taking electricity generated from all over the country (and even imports from abroad) to distribute as needed, in the instant it is needed. That electricity is generated from a variety of sources — not only solar. Wind, gas-fired, nuclear, and increasingly rarely, coal generators also put power onto our grid.
Remember electricity is generation-agnostic. It doesn’t care how it was made. Electrons are electrons — they are never green or brown.
But when you buy green electricity from a renewable supplier such as Pure Planet, you get power to your home around the clock (whether it’s sunny or windy or not) and the amount of electricity you use over a 12 month period is matched with green energy generated throughout that year and put on to the grid on your behalf. We verify this renewable generation — as does every green electricity supplier — through REGOs — Renewable Energy Guarantees of Origin certificates. Its great to have seen the origin in person.