A giant floating solar farm on the outskirts of London will be the largest facility of its kind in Europe, its developers have claimed.
Currently being installed on Thames Water’s Queen Elizabeth II reservoir near Walton-On-Thames the project is the result of a collaboration between Thames Water, and specialist solar developers Ennoviga Solar and Lightsource Renewable Energy, which is funding the initiative.
The array is made up 23,000 photovoltaic panels which are being mounted on a pontoon consisting of 61,000 floats and 177 anchors. The 57,500 square metre structure will cover around a tenth of the surface of the reservoir (an area equivalent to 8 football pitches).
According to Thames Water, when up and running the facility will have a total installed peak capacity of 6.3 megawatts and is expected to generate 5.8 million kilowatt hours in its first year. This electricity will be used to help power the nearby water treatment works.
The project is part of a wider effort by the utility firm to reduce its reliance on the grid. Last year, it generated 12.5 per cent of its electricity requirements from renewables.
As large solar installations have grown in popularity, developers are increasingly eyeing up the potential of siting them on reservoirs.
Last year, United Utilities installed a 45,500 square metre facility on the surface of Godley reservoir in Hyde, Greater Manchester. Whilst the UK’s first floating solar farm, an 800 panel pilot array, was installed on the surface of a reservoir in Wargrave, Berkshire back in 2014.
Meanwhile, engineers at Japanese firm Kyocera are in the process of building a plant that will dwarf even Thames Water’s latest project: a 180,000 square metre facility in Japan’s Chiba Prefecture that’s set for completion in 2018.
Presumably these will also cut down the water loss by solar radiation from the reservoirs as well.
What effect does the array have on the water? Very little light getting through.
As the solar cells age, are there any chemicals leaching out of them into the water? How do the panels affect water temps? Do the panels need cleaning underneath from algae attachment? What’s the cost per installed MW?
The water will be significantly cooler as most of the solar energy is removed: very nice for the Londoners G&Ts, take more energy to heat it up though.
The plant cost Is not given, but my most recent costings indicate £ 3m/MWe, i.e. £ 19.2m.
If this right the 5800 MWh per year at a generous £ 100/MWh generate £580,000 / year: i.e. a payback of over 40 years – far beyond the likely life of the plant. This means enormous subsidies are being applied and added to the water bills of Londoners: at least they can afford them!
Pumped water storage would seem a better investment for UK plc.
JB’s last comment is unfair – whist the capital does have some residents with large incomes, the majority of those living in London are far from well-off, and suffer high housing and living costs.
Yes, London has much to offer if you enjoy city life; but it’s an expensive place to live.
To Graham,
Sorry, was not meant as a deep social comment and was certainly unfair: more a reflection of the frustration of us northerners with the wealth distribution between north and south.
Jack
Do you have knowledge that of Thames Water are paying or have you made and educated assessment based on current prices. If so with Thames Waters buying power, I’m fairly certain that they could negotiate a large discount on the cost of the installation, so the price might be over pessimistic?
John, figures were based on 2015 iea (USA) figures for generating costs, similar to recent EU assessments: Link is below. Thames Water ought to let us know their budget in my opinion.
http://www.eia.gov/forecasts/aeo/electricity_generation.cfm
thank you for those figures
pumped storage could help london as the seas rise. tidal lagoons being trialled in south wales need to be designed to link with others 25 m high from North Devon. these can then be linked via sliding gates supported by giant caissons and access road/rail above built high enough to allow container ships through below (in the medium term) and to allow raising of the lagoons. Aren’t there are 7 metres of sea rise coming our way from Greenland and eventually 70 m from Antarctica..
Then a semi-saline lagoon created inshore from London’s offshore airport Hub with similar access links could get emptied with the surplus wind-power from turbines accessed from the roads and exchage of wildlife / flushing of silt allowed from the occasional operating of lower level gates.
Good engineers must surely be thinking of finance simplifications for contributions to these larger projects to add to standard funding mechanisms to cope with 22nd C needs.. such as credit creation charge that could moderate inflation regionally and DIRECT investments to real value and quality of life free from fear..
In the picture the solar cells only appear to be about 10-15cm above the water level. I wonder if this is not enough to cope with any swell whipped up on a windy day. Also I wonder about what the effect of the covering so much of the lakes surface will do to the eco-systems underwater. It is unlikely the lake become stagnant due to the fairly rapid water replacement. However much plant life will die, therefore the whole eco-system of the reservoir could crash. But I do understand the reasons for going this direction, much due to the cost of land near our cities. This fact especially applying to Japan, where the density of living space is much greater that the UK
Hi John
If this reservoir is steep sided and deep, the only plant life will be in the margins. This is because the sunlight only penetrates water to a shallow depth. If the level falls periodically by two to three metres the plants die. Also as long as the surface is not covered completely the wind will aerate the water to stop stagnation. Providing the panels are placed on the correct type of reservoir there should be little or no impact on the ecosystem.
The initial scheme was on the Big Brother Corp news today. It looked very impressive and well engineered and of course ticked all Big Brother’s green boxes.
However, to be really impressed I would like to see the real costs and benefits of the scheme………..pigs might fly………..
Scheme will have cost c6 million gbp. pay back is roughly 15 years factoring in inflation and expected interest rate over 12-15 year period. People forget the civils element is extremely minor and normally reflects c10%-20% of solar schemes.
John, thanks for the info, is the £6m an actual cost?
if so it means that the cost / MW installed is £1m/MWe which is far lower than any published figures for PV generation. The IEA indicative price is £3m / MWe. At £1m/MWe solar-generation could probably afford the battery back-up needed to cover the unreliability aspects.
Looks like good news for PV.
Expected Life of 25+ years for the PV panels. How about the life of the floats under water on one side and exposure to rain, wind and dust on the top? Is the float material corrosion proof to survive for 25 years? How about periodic maintenance and breakdown maintenance if any?