There is no doubt that the use of farmland to develop solar farms has become a major talking point in rural Ireland. Perhaps even more so as many of the solar farms which have navigated the planning system over the past few years, are now being built and are actually visible.

Despite solar farms set to occupy only a small fraction of the country’s farmland – as little as 0.2% – the problem for many farmers is that it is often Ireland’s best farmland.

There are arguments for and against. Yes, farmland is essentially taken out of action when a solar farm is built. While it may be farmed by sheep, it is a stretch to call it farming to the same intensity as before. On the other hand, farmers have the freedom to use their land as they choose, and undermining that right could be a slippery slope.

The leases being offered to farmers are substantial, and as not every sector is doing as well as others, this can transform the farm family’s income. Therefore, farmers should not be criticised for accepting such deals.

One thing is for sure, this debate is only going to heat up, with many politicians now calling for a solar farm review.

However, what if there was another solution? A way to develop large-scale solar farms without using farmland. Semi-state energy providers Bord na Móna and ESB are attempting to do just that by developing a number of solar farms on its bogs which were formally used for peat production.

Merits

On the face of it, constructing solar farms on former peat-harvesting bogs makes a lot of sense. Areas of cutaway bogs offer scope for significant scale and are often in flat, low-lying locations. Where peat harvesting took place, there is a good chance there was a power station nearby, so it is likely a sizable solar farm that could connect to the grid. These sites are likely to be relatively isolated and may still be well-drained.

Bogs can also provide recreational amenities, with planned projects aiming to develop these onsite alongside community benefit funds. Crucially, they do not remove farmland – particularly high-quality farmland – from agricultural use.

Concerns

There is little information about how the construction and operation of a solar farm might affect peatland, however. We know that peatland habitats can be easily disturbed, and a reduction in rainfall and sunlight below panels may affect vegetation composition. Peatland habitats, even those subject to extensive harvesting, can be home to an abundance of biodiversity which are highly sensative.

Peatlands are also the largest land-based carbon stores on the planet. Although they cover less than 3% of the Earth’s land surface, peatlands store twice as much carbon as all the world’s forests. Any ground disturbance or drainage could lead to the release of carbon.

Drained peatland can, in itself, be a major source of emissions, and building a solar farm on it will prevent the bog from being rewetted and becoming a carbon sink once again. While an entirely different type of renewable development, last year Nottingham Trent University researcher Guaduneth Chico stated in a study that the long-term impact of developing wind farms on peatlands is not yet fully understood. He argued that wind farm development affects peatland water systems, which can, in turn, significantly impact the entire ecosystem.

JV with big plans

In April 2017, Bord na Móna and ESB announced a co-development agreement to develop solar farms in four locations in Roscommon, Offaly and Kildare, which will provide 500 MW of renewable energy, enough to power 150,000 homes per annum. They assessed Bord na Móna’s 198,000ac land bank in strategic locations across the Midlands which are suitable for large scale solar energy projects. Below are two notable projects, both located on areas which saw extensive peat harvesting over the years.

Timahoe North Solar Farm

After initially being refused by Kildare County Council, permission for the 70 MW Timahoe North Solar Farm was granted by An Bord Pleanála.

The project is located to the northwest of Kildare, 3km from Johnstownbridge, in the 2,000ac Timahoe North Bog, which forms part of the Allen Bog.

The site has been subject to extensive large-scale commercial peat harvesting, which ceased 20 years ago. The harvested peat was once used to feed the now-demolished Allenwood power station. The Derryiron-Maynooth 110 kV electricity line crosses through the overall Timahoe Bog.

The Timahoe North Solar Farm consists of two areas of solar photovoltaic panels covering approximately 495 acres, as well as underground cables, recreation areas, a 110 kV substation, a 10.5 km private road and a 20 MW battery storage compound. The site is very flat, low-lying, extensively drained and has a strong electricity grid, making it an attractive site for a solar farm without taking an acre of farmland out of production.

While the site has many positive characteristics, it also presents challenges. During the planning process, 570 peat probes were taken, revealing peat depths of between 0.3 m and 4.5 m. Piled foundations need to be driven into the peat, deep enough to support the panels.

The cut bog also has biodiversity considerations, but the planning application states that the locations for the panels were chosen to avoid environmentally sensitive areas within the bog.

Extensive works are also required around the site. According to the planning application, the development involves the removal of 63,400 m³ of peat and the felling of 115ac of forestry.

The excavated peat/spoil will be stored in seven pits and used as required for reinstatement landscaping works, with residual material placed in peat repositories.

From reviewing the planning application, it was unclear how much carbon emissions would be generated from excavating the peat and how much emissions would be saved by the solar farm.

The application drew comments and submissions from the Irish Peatland Conservation Council, Butterfly Conservation Ireland, BirdWatch Ireland and Peter Sweetman. The Timahoe 110 kV substation and Timahoe North Solar Farm was recently energised, meaning the project is now exporting power to the electricity transmission network. The project secured support in the Government’s Renewable Electricity Support Scheme and will operate for 35 years.

Blackwater solar farm

Planning permission for what is anticipated to be Ireland’s largest solar farm is expected to be lodged next year and will be built on the Blackwater Bog. The Blackwater Bog, located in northwest

Offaly, less than 1 km south of Clonmacnoise, is approximately 5,777ac in size and was formerly used for the production of milled peat to fuel the Shannonbridge power station. Bord na Móna and ESB intend to seek planning permission for a 988ac solar farm on the bog, producing 160 MW of electricity.

The project will also involve the construction of a 110 kV onsite substation, which will connect, via 2.5 km of underground cable, to the national grid at the existing 110 kV ESB Networks at West Offaly Power Station. The proposed solar farm will aslo include approximately 24km of new internal road networks.

Bord na Móna and ESB envisage that the solar farm would be integrated into the habitat rehabilitation plan for the bog. The solar farm will have a projected lifespan of 30 years.

Building solar farms on bogs

Building solar farms in boglands is a new and interesting development. As alluded to in this article, it raises many questions, such as whether special infrastructure is required, how drainage is managed, what impact it might have on biodiversity and whether there will be emissions resulting from the disturbance of carbon-rich peat.

To learn more about the process, the Irish Farmers Journal reached out to Bord na Móna.

Little information was provided on the above topics, other than the following statement:

“The project (Timahoe North Solar Farm) has been developed with consideration for biodiversity, and we have measures in place to protect the ecology within its surroundings.”

In short