Frequently Asked Questions (FAQs)
How long does it take to build a solar (photovoltaic (PV) panel) farm?
The construction and installation period is usually around 16 weeks (or 4 months) from start to finish. After construction, access for operations and maintenance activities are usually limited to 4 or 5 times per year.
How many HGV lorry deliveries will there be to build the 5MW Penny Hill solar farm?
There will be around 70 deliveries (on normal sized HGVs) need to get all components associated with the solar farm on site – including all the solar panels themselves, fixings and cables.
What does a solar farm look like in the landscape?
Placing solar farms on flat south-facing land or gentle slopes also helps to minimise it appearance in the landscape. Likewise, while existing natural screening is sought, any shadows cast need to be avoided in the design of the panel layout, otherwise the site would fail to yield the optimum electricity generation for the national grid. A landscape and visual impact assessment is commissioned for all solar farm planning applications and accompanies the planning application.
How big is a solar farm?
Banks Renewables’ Penny Hill 5MWp Solar Farm will be approximately 6 hectares (c14 acres) or around 5 football pitches in size. A 5MW solar farm provides enough clean, green, electricity to power approximately 1,320 homes (that is enough to provide power for Ulley with its population of around 200 and around 80 homes about 17 times over per year!)
How big are the solar panels?
Solar panels are typically around 1m by 1.6m in size and are mounted between around 1m and 2.75m above the ground (the maximum height of the solar panels is around 3m – depending on the angle/frame design), providing clearance for plants and other habitats to remain.
Do solar farms cause any changes to the land?
No widespread levelling of the ground in advance of the installation work is required. There is practically no loss of soil coverage (less than 0.1 per cent) as a result of the solar farm as enough sunlight and rain can get through/between the panels to maintain the plant life. Correct and diligent management during the operational period can improve the soil quality through a significant increase in topsoil content, which can become depleted as a result of regular intensive cultivation.
How are the panels fixed to the ground?
In general, solar cells are attached to an aluminium frame, comprising two posts that are in turn bolted to galvanised steel posts that are pile driven into the ground. This arrangement avoids the need for a concrete base platform and reduces the removal costs at the end of the system life, as well as the carbon footprint of the mounting system. The depth of the steel posts is determined by engineering calculations taking wind conditions and ground conditions into account but is typically around 1m to 1.5m. Sometimes there is a need to install a small concrete foundation for an inverter and switch gear housings in order to ensure that these are installed on a level and stable footing. However, in each location, sensitive solar farm developers, like Banks Renewables, seek to minimise any levelling and concrete usage associated with these units.
Can farming continue on the land?
The solar farm does not mean an end to agricultural use of the site. Small livestock such as sheep can continue to graze around the solar panels for the lifetime of the solar farm (see picture above). Panels are mounted between 1m and 2.65m above the ground (maximum height 2.8m – depending on the angle / frame design), providing clearance for plants and other habitats to remain.
Do solar farms affect aircraft?
In Germany, Russia and the USA (where the solar industry is more established), several solar farms have been installed in close proximity to airports. In the UK there is a solar farm at Caddington which is near London Luton airport. There have been no reports of disturbances either from environmental tests or from open-space solar farm usage. In fact, pilots have been reported to use solar farms as visual markers for navigation.
Do solar farms create glare?
Solar cells are made to absorb as much light as possible and not to reflect it: they are light converters and have extremely low reflection levels, which increases the efficiency of the cell. Any reflection that may occur would be limited as the sun’s position changes all the time. Furthermore, reflected sunlight is always less intense than direct sunlight, because it is not possible for the full amount to be reflected. Preserving and indeed planting trees and bushes around solar farms can further screen them and help to further reduce the likelihood of passers-by experiencing glare.
How long does a solar farm last?
The Penny Hill wind farm, if it gets the go-ahead, will have planning permission for 23 years. Early solar farm installations around the world are now over 30 years old and still going strong. Based on manufacturers’ in-field experience and reliability testing, solar cells or PV modules probably last longer, and according to BP Solar are more reliable than just about any other capital investment in renewable energy. In 2003, BP Solar published the results of their analysis of warranty claims and reported that of more than two million modules in service over nearly ten years, approximately one-tenth of one percent were reported faulty, noting “this represents one module failure for every 4,200 module-years of operation.”* In other words, for every one thousand solar panels, we would expect experience the failure of only around ten modules in 40 years. At the end of the Penny Hill solar farm’s working life in 2039 (if it gets planning permission and built in 2016), the area outside Ulley can be restored at low financial and environmental costs – in contrast to fossil fuel or nuclear power stations.
* BP Statistical Review of World Energy, June 2010
What happens afterwards?
The modules and associated plant and equipment will be removed and the site will be returned to its agricultural use.