Cultivating a new generation of renewable energy down on the farm

Greenhouse gas emissions arising from agriculture have been the subject of increasingly heated debate in recent years. But relatively little attention has been paid to on-farm energy consumption and the potential for farm-based renewable energy generation.

And that potential is very significant. The Teagasc Marginal Abatement Cost Curve (MACC) has established that the cultivation of biofuel and bioenergy crops, along with the adoption of anaerobic digestion and biomethane and other on-farm energy savings, has the potential to account for a reduction of 1.37 million tonnes of CO2 per annum between now and 2030.

“We need to rethink the existing relationship between agriculture and energy due to the world’s finite supply of fossil fuels and the adverse environmental impact of using those resources,” says Teagasc energy and rural development specialist Barry Caslin. “The most visible renewable energy developments are wind and solar farms. However, before we even attempt to look at renewable technologies, we should examine how we can reduce our on-farm energy demand by becoming more energy efficient.”

A lot of young people out there don't necessarily want to do the same thing as their fathers and grandfathers. They want to do something different with the land

Large energy-using farm enterprises can benefit from a professional energy audit.

“Before you embark on an all-out energy efficiency campaign you need to determine where energy is used on your farm and within the various activities of your farm business,” says Caslin. “This will generally be achieved through an energy audit and the Sustainable Energy Authority of Ireland are now funding energy audits for all businesses including farms which spend at least €10,000 a year on energy and meet certain other criteria. Energy audits will not only identify energy efficiency measures but can also highlight situations where renewable technologies such as wind turbines, heat pumps, biomass boilers and so on can make sense.”

Revenue streams

There is also a growing interest in the farming community in developing new revenue streams from renewable energy investments.

“An awful lot of young people out there don’t necessarily want to do the same thing as their fathers and grandfathers,” Caslin explains. “They want to do something different with the land, but they have to be confident that it will work for them. All we can do is point them in the direction and give them the information they need. There are lots of options available and we discuss them with farmers.”

Solar PV is one of those options. “The Department of Agriculture, Food and the Marine offers 40 per cent grant support for farm-related solar panels through the Targeted Agricultural Modernisation Scheme (TAMS),” says Caslin. “The farm businesses most likely to benefit are those with high and consistent electricity usage that can install solar to offset the cost of power bought from the grid.”

He points out that installation costs have fallen considerably over the past decade, but more recently have plateaued at around €800-€900 per kW for ground-mounted solar. Rooftop solar is slightly more expensive.

“Any farm business considering investing in solar should carefully tailor the project to the annual energy profile of the business,” Caslin advises. “Solar PV still makes sense, but in many cases, solar PV combined with storage will be the best combination. Although we’re not quite there yet due to the cost of batteries.”

Benefit

There are other ways for farmers to benefit from solar energy. “The Renewable Electricity Support Scheme (RESS) has raised interest among solar developers looking to acquire land for large-scale solar farms, and they are offering rents of typically €850-€1,200 per hectare, index-linked for 25-30 years,” he explains. “With improved panel technology, solar PV developers are getting more for their money per acre than a few years ago, so it is worth landowners trying to secure additional income, such as a payment based on a percentage of turnover or output. Developers generally resist this, but if you don’t ask, you don’t get.”

While there has been very little activity to date in the Republic of Ireland’s anaerobic digestion (AD) biogas sector, a rapid increase is anticipated as a result of the decarbonisation targets for the natural gas sector.

“I expect that most AD development will be for larger-scale and gas-to-grid plants and farmers will most likely be partners in these large projects and receive income from leasing the site and supplying feedstocks, and will benefit from a free or even cheap supply of heat and power.”

Other options include wind and battery storage, but Caslin points to a current barrier to their adoption. “There are some anomalies in the system and farmers can’t sell excess power back to the grid. However, we do see that situation changing over time as a result of the adoption of the green agenda at both EU and national levels.”