This summer will be another important period for the UK’s rapidly changing renewable energy sector. Revised Feed-in Tariff rates for solar photovoltaics and anaerobic digestion are due to come into effect from August, while July will see the first phase of the £860m Renewable Heat Incentive begin.

With precise details and payment rates still being confirmed at the time of writing, it is unclear exactly how each scheme will benefit farmers investing in renewables. But returns for larger scale solar (over 50kW) are likely to become less attractive compared to the original rates, while the small increase proposed for AD could make some projects viable.

The introduction of the RHI will also benefit those installing equipment such as biomass boilers, solar thermal panels and ground-source heat pumps. Like the FiT, the RHI will provide long-term (20-year) “tariff” payments for heat produced from approved installations, provided a use for that heat can be demonstrated.

AD plants using Combined Heat and Power (CHP) generation are also likely to be a beneficiary of the RHI and installations should be able to claim FiTs and the RHI for the electricity and heat produced.

For farmers with large heat requirements, such as for heating glasshouses, or drying grain, the RHI could make it worthwhile investing in renewable heat technology, although balancing demands throughout the year will be a challenge for many.

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Perhaps the biggest uncertainty for arable growers considering technology such as AD is the government’s rather cautious attitude towards the use of energy crops. Both the RHI launch document and FiT review are wary of any scheme causing large scale use of crops in AD, although they acknowledge the need for “some” energy crops in farm-based systems, alongside slurries or other waste.

“We note concerns that an increase in FiT tariffs for farm-scale AD would lead to wholesale expansion of the diversion of land and food to energy crops. This is not the intention of the proposed tariff changes and the government will ensure that any necessary controls are put in place to ensure that this does not happen,” the FiT review says

This attitude differs somewhat to the stance of other European countries, such as Germany, which has seen rapid growth in the number of biogas plants using crop-based feedstocks on the back of favourable incentives, says Lucy Hopwood from the National Non-Food Crops Centre.

“In Europe bonuses are offered for either slurry or crop inclusion, but this has in some cases distorted the market,” she says. “There are now over 4,000 crop-only systems operational in Germany, driven by their incentives, and this is not something we want to replicate in the UK.

“There still remains a place for crop material in AD to boost the energy output, either purposely grown or residues from existing cultivations; however, this is being approached with caution in the UK – it is very much a case of crops being acceptable ‘in the right place, at the right time’ with no blanket policy to include or exclude them from the mix.”

The greatest scope for growing energy crops is likely to be on marginal land or areas unsuitable for food crops.

Quality assurance

For small-scale projects (generally less than 50kW), both installers and equipment will need to be certified under the Microgeneration Certification Scheme or equivalent standard (such as the CEN Solar Keymark Scheme) to qualify for FiTs or RHI payments.

MCS is an internationally-recognised quality assurance scheme, similar to the Gas Safe Register. It covers the following technologies: wind, small-scale hydro, solar thermal hot water, ground source heat pumps, air source heat pumps, biomass, solar photovoltaic and micro-CHP.

You can find a searchable database of MCS-accredited products and installers at www.microgenerationcertification.org, while more on the solar scheme is at www.estif.org/solarkeymark.

• For further information about FiTs and the RHI, go to www.decc.gov.uk. Farmers Weekly’s website also has the latest renewable energy information at www.fwi.co.uk/farmenergy