Grid capacity is the number one issue that limits the viability of potential solar farm sites. To be of use, the electricity generated by solar farms needs to flow into the local electric grid. That means that there needs to be sufficient capacity in the local network to accept that power. That information isn’t readily available and can only usually be determined by making - and paying for - a direct application to the network operator.
Before committing to that cost, therefore, it is worth considering the other site characteristics which determine whether a solar farm is practical - and which can be more readily identified.
Solar farms typically need sites of at least 120 acres to be economically viable, although smaller sites can sometimes work too if there is a large energy user nearby who will buy all the power direct.
The size of the individual fields can be important too - fewer field borders make panels more cost effective to install. Smaller fields can work too, but the increased inefficiency of the design means that rents can be a little lower.
Sites will need to be accessed from the road during their construction,
Once they’re operational, solar farms don’t generate much traffic, but they will be visited from time to time for maintenance and monitoring purposes. That means it needs to be possible to access potential sites from the road - even if only a minor one - as well as being able to gain access from field to field.
Ideally, sites would be flat, or nearly flat. Solar panels need to be angled towards the sun, so when sites aren’t flat, south facing slopes work best. Although development can be possible on east or west facing sites, north facing slopes are usually subject to significant shading which can preclude development.
Undulating ground isn’t ideal either. To be as efficient as possible - and therefore generate the most power and pay the most rent - solar farms need consistent, long runs of panels which can be hard when sites undulate.
When a solar farm is proposed on agricultural land, there is balance to be found between the need for the renewal energy and the loss of the land from food production. The quality of the farm land can therefore be an important consideration. Where it is “Best and Most Versatile” land - with an Agricultural Land Classification of 1, 2 or 3a - it can be harder to secure planning permission. It can be easier on land that is classed as grade 3b or below.
Natural England publish maps which give an indication of agricultural land quality across broad areas, but there’s no substitute for a site specific assessment. These provide a more definitive answer and can sometimes produce a different result to the high level mapping.
Permission can still be granted for solar farms on higher quality land though, especially when there is no alternative because the whole area is of a similar classification. Schemes don’t automatically mean all the site is lost to food production either. It can be possible to continue using the land around the panels for grazing sheep, for example, although usually means panels are installed at a lower density which can reduce efficiency (and therefore rental incomes).
Although solar farms are usually in greenfield sites, they usually aren’t in areas formally identified as green belt in the council’s local plan. Green belt designation is the highest degree of protection from development that our planning system can provide. While some projects have been able to secure planning approval despite being located in the green belt, these projects are higher risk. Locations outside the green belt are therefore preferable.
Fairly obviously, water and electricity aren’t a great mix! You can check whether your site is in a designated flood risk area for free on the Environment Agency’s website.
Planning permission can be more challenging to secure if the site is intensely overlooked, with lots of neighbouring homes - that’s why you usually find solar farms a little way from the edge of towns and villages. Well sited projects on flat ground can sometimes include landscape planting at their perimeter that can entirely shield them from neighbours.
The amount of detail that needs to be considered can seem daunting, but that’s where we can help. Working with our joint venture partner, we can assess your site’s suitability for a solar farm - including making an initial enquiry to the network operator about grid capacity - entirely without charge, and without any commitment from you. After we’ve done that, if we think a solar farm could work in your land we’ll make a formal proposal for you to consider.