Solar Photovoltaics

The FIT scheme used to be one of the main incentives for installing  solar PV on farms, however the FIT scheme has now closed completely.

The government are consulting on future support and payment mechanisms for small-scale low-carbon generation including Smart Export Guarantee (SEG) which could benefit Solar PV.

The opening up of energy markets, smart metering, battery storage, electric vehicles, future proofing businesses and other emerging markets may all provide various opportunities for solar moving forward.

• Carry out an energy audit.
• Monitor and reduce energy use.
• Benchmark — how do you compare with others?
• Assess all opportunities for renewables — for example a mix of renewable technologies such as wind and solar may be best suited to your farm.
• Compare information from different suppliers.

Siting is a key consideration to maximise output – solar PVs need to be sited in a south or near-south facing direction.  Panels can be retrofitted to building roofs, incorporated into the roof design as tiles in the external layer or, as seen in larger schemes, mounted at ground level in fields forming a bank of solar arrays.

Ideally, a PV array should be connected to the National Grid with an inverter to change power from DC (direct current) to AC (alternating current). This can also allow two-way metering where power can be sold directly to the grid when a surplus of energy has been generated or buy in electricity when the demand exceeds the current level of generation.

Aside from making sure the panels are clean, maintenance requirements are low. Some manufacturers are claiming panel life spans in excess of 35 years if correctly maintained, but performance will gradually deteriorate over time. Inverters may need replacing during the life of the panels, at around 10 years.

Planning permission may not be required, though guidance from the local planning office should always be sought at an early stage.

Solar has seen a massive increase in efficiency coupled with a massive decrease in costs over recent years, making it an increasingly viable option without incentive payments. Solar PV is most cost effective when installed as part of a new build as opposed to retrofitting.

Costs will vary depending on your site and size of scheme and PV in particular benefits from economics of scale. As a rough indication of costs, a 10kWp system covering around 70 m² of roof space with 40 solar PV panels, could cost in the region of £9,000.  Depending on geographic location, demand and how much electricity you generate and use on site, the payback benefits will vary.

Solar PV technology is improving quickly and new markets and opportunities are emerging which could help offset costs.

Solar panels for heating and hot water use different technology to solar PV.  These systems rely on the heat in sunlight to warm water in special panels or tubes.

The system consists of a roof mounted collector plate, fixed to an unshaded south or near-south facing roof, a hot water storage tank and a pumped circulation system.  The most common type of collector units are either a flat plate or evacuated tube design.

Typical supplementary systems can cost from £3,000 upwards and a correctly sized unit can provide 100% of domestic hot water during the summer months.

RHI payments may be available for solar thermal installations.