BIOMETHANE PRODUCTION HINGES ON LOCAL BUY-IN
Plans to supply gas to 64,000 homes with renewable gas from Mitchelstown were announced by Gas Networks Ireland (GNI) some time ago, but it still remains to be seen if local farmers will buy into the scheme, reports Marian Roche.
The facility is to be built at Corracunna and Garryleigh outside Mitchelstown, on the north side of the town on the road to Kilbehenny. It will be where biomethane, produced within a 60km catchment area of the plant, will be injected into the national grid.
Plans to supply gas to 64,000 homes with renewable gas from Mitchelstown were announced by Gas Networks Ireland (GNI) some time ago, but it still remains to be seen if local farmers will buy into the scheme.
The facility is to be built at Corracunna and Garryleigh outside Mitchelstown, on the north side of the town on the road to Kilbehenny. It will be where biomethane, produced within a 60km catchment area of the plant, will be injected into the national grid.
The biomethane will be supplied, it is envisioned, by local farmers or co-operatives of farmers. Gas Networks Ireland have stated that the company are ‘in discussion’ with potential biomethane producers, but have not confirmed if any contracts have been arranged or decided upon.
The production of the renewable natural gas is, very simply put, as follows: a farmer, or co-operative of farmers, will invest in an Anaerobic (‘without oxygen’) Digester (AD). The digester will be fed with slurry, silage and food waste, which will breakdown to form a biogas. After being transported to the injection facility, the carbon dioxide (which makes up 40%) will be removed from the biogas, leaving an end product of biomethane.
A second important product of this process is the high-nutrient digestate produced by the waste material, which is a valuable bio fertiliser.
The facility, which will be operated by Gas Networks Ireland, requires the input of biomethane gas from between 20 and 28 Anaerobic Digesters, either 20GWh or 40GWh in size. To ‘feed’ a 20GWh Anaerobic Digester, 35,000 tons of gross feedstock annually is required, of which 50% must be animal slurry. The cost of the smaller 20GWh AD is quoted as €5 million, and it is the producer, or farmer, who shoulders the cost.
Ian Kilgallon of GNI in a presentation last June, envisioned that the most likely scenario for farmers who buy in to the scheme would be that circa eight farmers would form a ‘ co-operative’, combining silage, slurry and food waste to a shared AD. He was speaking at An Teagasc’s Signpost programme, which is a campaign to lead climate action by farmers.
However, at a cost of €5 million per 20GWh digester, or €8 million for a 40GWh unit, it still remains to be seen how any farmer, or group of farmers, will be encouraged to sign up to the scheme.
To supply 64,000 homes, Gas Networks Ireland needs to have at least 20 AD units, at €5 million each, producing biogas within 60km of Mitchelstown. Currently, there is no capital grant funding available to invest in an AD in Ireland. However, while it is true that other European countries do not provide capital funding either, they have implemented incentive schemes like feed-in tariffs.
E.U. TARGETS
One source told The Avondhu that, while the plans for the implementation are noble, there currently is no policy framework driving the production of biomethane in Ireland. Gas Networks Ireland have not confirmed if any farmers have entered into a contract with the company for the production of biogas.
The Biomethane Injection Facility planned for Mitchelstown is intended to help Ireland meet its EU target of replacing a minimum of 3.5% of the gas used in heat with renewable gas by 2030. As of six months ago, Ireland was bringing up the rear in terms of having the relevant technology installed, with just one facility in the country built, a biomethane injection facility in Cush, Co Kildare. For comparison, Germany had 232 and the UK had 80.
According to Mr Kilgallon, France on the other hand which has a mandatory target of 10% by 2030, are four years ahead of their target, and could be considering export. At the time last summer, France were rolling out three biomethane facilities a week. However, he put a positive spin on Ireland’s position, stating that the country had the advantage in that we could learn from the those leading the way.
“We’re a little bit behind, but with a lot of opportunity to grow.”
The choice of Mitchelstown is a purposeful one. The injection facility needs to be close to feedstock and with good road access. With a high density of farmland in the surrounding area, Mitchelstown is ideally placed to facilitate the plans. Gas Networks Ireland say that the catchment area of the waste needs to be within 60km of the injection facility.
64,000 HOMES
At full capacity, Gas Networks Ireland claim that the plant in Mitchelstown will be powering 64,000 homes. However, initially the plan is forecast to be rolled out in phases, with 25% operational by early 2024.
Biomethane, as a carbon neutral product, is a considered a better alternative to gas produced by fossil fuels, and is a ‘compatible substitute for natural gas’. Biomethane is also a useful way of using up animal manure and food waste from the environment, and can also mitigate methane emissions by converting the gas into CO2.
Natural gas is the largest source of electricity generated in Ireland, accounting for 52% of all electricity generated in 2020, while wind accounts for 37%.
Gas Networks Ireland are currently in discussion with a number of potential biomethane producers, and interested parties are encouraged to email renewablegas@ gasnetworks. ie to register their interest.