Ground-mounted solar panels: when your garden beats the roof

Are ground-mounted solar panels worth it?

Ground-mounted solar panels, also called ground-based, free-standing or floor mounted solar panels, sit on a frame in the garden rather than on the roof; this guide covers domestic and residential arrays, not solar farms. They are worth considering when the garden offers a better spot than the roof: less shade, a better direction, or space the roof cannot provide. Compare the garden system with the roof option on panel capacity, annual output and installed price. For the same panels, unshaded, a south-facing frame tilted to the optimum angle generates about the same as a south-facing roof (within 1 per cent in our five places) [1]. It makes 5 to 8 per cent more than a south-east or south-west roof, 24 to 30 per cent more than an east or west roof and 80 to 92 per cent more than a north-facing one, by our calculation from PVGIS [1]. MCS's own generation tables also come from PVGIS, using a different dataset multiplied by 0.8 [3]. This compares output per panel: an array within the planning limits is small (see below), and the frame and trench have no official price [19].

Shade can undo the gain. Inclination, orientation and shading are the three main site factors that influence a system's performance, MCS says [3], and a frame in the garden sits lower than a roof, nearer fences, hedges, trees and the house itself. PVGIS allows for hills and mountains, not those [2]. By our calculation, the frame stays ahead of an east or west roof only while shade costs it less than 19 to 23 per cent of its output, a south-east or south-west roof less than 5 to 7 per cent, and a north roof less than 44 to 48 per cent [1], so an installer's shading check on the actual spot is what settles it. A lower frame costs little in output: tilted at 20 degrees instead of the optimum angle, it made 4 to 5 per cent less in our five places [1].

What are the disadvantages of ground-mounted solar panels?

A ground array is more work than a roof one, and the planning limits are tighter. The drawbacks:

• Garden space, kept clear of shade, and the planning limits on area and height below.
• A ground mount frame and its foundations. Solar racking for a ground mount is outside MCS's certified pitched-roof kits, so an MCS-certified installer must be able to show a structural assessment and wind-loading calculation for it [12][13].
• A longer cable run to the house, which may need a trench. MCS asks for the AC cables, from the inverter to the supply, to be sized to keep the voltage drop low: about 1 per cent is practicable for most homes, and up to 3 per cent may be for long runs [12][13].
• No official price for a ground mount solar system. The government's cost data are split by system size, region and type of building, not by roof or ground mounting [19], so the extra cost is for the installer to quote.

When it is not worth it. If your roof faces south and is unshaded, a garden array gains almost nothing and adds a frame and a trench. Start with a quote for the roof; the installer's survey shows whether the garden is worth pricing as well.

Do I need planning permission for ground-mounted solar panels?

Not if the array stays within your nation's limits for a garden installation. Can I put solar panels in my garden in the UK, then? Yes, within those limits; in England and Wales, check that the rights have not been removed by a condition on your home's planning permission or an Article 4 direction [9][17]; in England some cases also need a prior approval application first [4]. In Wales, Scotland and Northern Ireland these rights are for houses, not flats [5][7][16]. England changed its rules for houses on 27 August 2026: more than one array is now allowed, each with up to 9 sq m of panels, and the height limit depends on where the array stands [4].

Beyond the limits, a planning application is the route. In England the fee for work in the grounds of a house is £272 (not flats); your council confirms the category. Prior approval, where needed, costs £249 for the cases the fee schedule lists [10]. These rights cover the grounds (curtilage) of a house, or in England also of a block of flats, only [4][5][6][8]: solar panels in a field or paddock beyond them fall outside the garden rules, so check with the council first. The rules for every kind of installation are in do you need planning permission for solar panels.

How many panels fit within the limits?

Fewer than people expect. Using one common panel size, 1.762 m by 1.134 m and 425 to 450 W on its maker's datasheet [11], 9 sq m holds 4 panels, about 1.7 to 1.8 kWp, by our calculation. Where no dimension may exceed 3 m including any housing, about 3 fit: two upright side by side and one on its side above, 2.27 m by 2.90 m, which leaves about 10 cm for the frame; with a bulkier frame, 2.

Can I install ground solar panels myself?

You can fit the panels yourself. But the Energy Saving Trust says you still need a qualified electrician to connect them, and it does not recommend installing solar panels yourself [14]. Smart Export Guarantee suppliers are not obliged to pay for exports from an installation that is not suitably certified, with the installer certified too, such as through MCS, though they can choose to [15]; the scheme covers Great Britain [18]. The installer also registers the system with the local network operator [14].

What to ask an installer about a ground-mounted array

1. Where exactly will it stand, and what shading check was done on that spot?
2. Which planning route does it rely on: the permitted development limits for your nation, prior approval, or an application?
3. Which ground mount solar frame, racking and foundations, and can they show the structural and wind-loading calculation?
4. How long is the cable run, what trenching does it need, and what voltage drop is the design?
5. What is included in the price: groundworks, trench reinstatement, any planning fee.

Prices by system size are on solar panel costs, and whether panels pay back at all is on are solar panels worth it.