Dr. Pat Dillon:

I thank the committee for the opportunity to speak on the topic of biomethane renewable gas. Teagasc as an organisation is fully committed to embracing biomethane and the establishment of a demonstration AD facility at our Grange campus.

Various EU and Irish policy and industry targets exist that provide a key role for biomethane in the decarbonisation of the energy sector and a diversification opportunity within agriculture. As the agricultural industry is Ireland’s largest contributor to greenhouse gas emissions, accounting for 37.5% of the emissions in 2021, it is a key area of focus for reductions. The EU has set the target of building a net-zero carbon economy by 2050, as outlined in the European Green Deal in January 2020, along with ambitious goals in the farm to fork strategy.

On a national level, the Food Vision 2030 and Ag Climatise reports both include goals around AD. Climate Action Plan 2023 increased the target for AD to 5.7 TWh of biomethane by 2030, which will require in the region of 150 to 200 AD plants. This recognises the role AD can play in reducing emissions and creating a circular bioeconomy. We have considerable ground to cover between now and 2030 to achieve these targets.

AD is legislated within the EU by RED II, which sets a target of 32% of energy coming from renewable sources by 2030. RED II sets limits for greenhouse gas emission offsets by the generation of renewable fuels of 65% for transportation fuels and 80% for electricity, heating and cooling by 2026. Ensuing from these various EU policies and industry documents, it is also recognised that the agricultural sector will have a part to play regarding the decarbonisation of the energy generation sector.

The development of biomethane energy generation in agriculture has the potential to have three benefits for Ireland, including the agriculture sector. Enhanced energy security through the displacement of fossil fuels will bolster our national economy's self-reliance through the consumption of locally generated renewable heat or electricity in place of electricity or heat generated from imported fossil fuels.

Second, in respect of farm diversification, income generated from selling biomass to an AD biogas plant will provide additional income streams for farm families in rural areas and provide a land use alternative. Third, renewable biomethane generation is better for the environment and will help to contribute to our national efforts in the area of decarbonising the heat and electricity sectors.

The Department of Agriculture, Food and the Marine, in partnership with the Department of the Environment, Climate and Communications, is currently developing a national biomethane strategy that will define the strategic direction for the production and delivery of the 5.7 TWh of indigenously produced biomethane. Teagasc is a contributor to this working group.

I will talk about AD in Ireland in context. AD has been operational in Europe on a small scale in niche areas, particularly since the oil crisis in the late 1970s. On a small scale, the biogas generated, which typically comprises 55% methane and 45% carbon dioxide, is combusted for heat. Since the 1990s, there has been a development of large-scale AD utilising the biogas for electricity generation, driven by legislation and incentives. The electricity is generated from a combined heat and power, CHP, unit, with a trend to increasing biogas storage on site and providing power on demand at a premium. More recently, biomethane has come to prominence whereby the biogas is upgraded to greater than 99% methane, which can be injected into the gas grid, with certificates generated and traded for this renewable or green gas.

To date in Ireland, the development of AD has been slow by comparison with other EU countries. A combination of planning and licensing, grid connection costs, prevailing electricity tariffs, financial issues and uncertainty in waste policy have led to relatively few plants in Ireland to date. AD plants generally require financial support to compete with fossil fuels, which has been the case in establishing the respective industries across Europe.

I will move on to the role of Teagasc in biomethane renewable gas research. Teagasc has been very active in the area of energy in agriculture for many years and launched its first dedicated publication on energy use in agriculture in 2011. Furthermore, Teagasc has compiled a suite of factsheets on energy use and renewable energy generation covering all farm enterprises, which were updated recently. Biogas has been a key measure in the Teagasc marginal abatement cost curve, MACC, since it was established in 2012. Teagasc is also a key partner at the Energy in Agriculture show at Gurteen College each year.

The Climate Action Plan 2023 target of 5.7 TWh of biomethane by 2030 is equivalent to approximately 10% of the total natural gas demand in Ireland. Meeting this target will require a substantial quantity of feedstock that is both biomass and manure. With more than 80% of agricultural land in Ireland in grassland, the potential for grass resources is substantial. Indeed, the national heat study showed that the available biomethane grass resource could be 4% to 8% of Ireland’s current gas fuel demand, and that could rise to 11% of current gas demand by 2030 if changes to livestock occurred and land was freed up from other areas. It is evident from this that the 5.7 TWh target by 2030 is achievable and biomass-based resources, such as grass-clover silage, will have a key role in meeting this potential, provided economic, environmental and social sustainability is considered.

Teagasc estimates that at a national level, the total land area of 120,000 ha, which is less than 3% of available land, will be needed to provide silage to feed the AD biomethane plants required to reach the 5.7 TWh target. In addition, winter slurry from 1.3 million cattle will be required, which represents approximately 20% of all cattle slurry produced in Ireland. The above assumes an equal mix of grass silage and slurry on a fresh weight basis. The above land area requirements are based on current average yields on Irish grassland farms, in which case some displacement of livestock is a likely consequence, or it could displace some existing tillage crop production. The availability and transportation costs associated with the slurry is an important consideration such that proximity of the AD biomethane plants to large resources of livestock slurry is paramount.

Research at Teagasc has indicated that there is substantial scope to increase the availability of forage from Irish livestock farms in excess of livestock requirements by improving grazing management practices. For example, beef farms typically utilise about 6 tonnes of grass dry matter per hectare, which is far below that being achieved on the top-performing demonstration farms, where grass utilisation typically exceeds 10 tonnes. In a scenario where grassland management and utilisation practices improve, the Climate Action Plan 2023 target could be met with little livestock displacement. Importantly, however, increasing the availability of forage should not be achieved by increasing the application of nitrogen fertiliser due to its impact on greenhouse gas offsetting and forage production costs. Also, use of chemical nitrogen to grow biomass for anaerobic digestion would make it difficult to achieve RED II sustainability criteria.

Current research at Teagasc indicates that the production of forage crops with the capacity to produce high yields with low levels of fertiliser nitrogen, such as red and white clover crops, are best placed to meet the feedstock requirement for the AD industry. Furthermore, improving grasslands to support biomethane must be consistent with the national biodiversity strategy, which aims to conserve biodiversity in the wider countryside through the enhancement of high nature value farmlands.

The use of grass resources for AD biomethane has a distinct advantage from a farm diversification perspective in that it is a familiar practice for livestock and crop farmers. In this context, the willingness to adopt land use change is being assessed by an SEAI-funded farm level economic, environmental and transport modelling, FLEET, project led by Teagasc, which is identifying farm scale, landscape level and national level economic and environmental implications of farm-supplied alternative feedstocks for AD at a regional level. Clearly, the financial returns to the farmer will have an important bearing on the acceptability of producing grass for AD biomethane. The traded value of grass silage can be used as a guide for this diversification option; however, an additional premium is likely necessary, the extent of which being influenced by the individual farmer’s commitment to their existing enterprise and prevailing attitude to innovation and change.

Digestate is the residue of the feedstock that remains following the digestion process. The nutrient content of the feedstock is largely retained and, therefore, digestate is a valuable nutrient for grassland and cereal crops and can replace artificial fertiliser. Nutrients in agricultural AD digestate, particularly nitrogen, are more freely available for plant uptake than in untreated organic slurry or waste sources. For example, nitrogen availability in digestate is increased by up to 10% and, for this reason, application using low-emissions slurry spreading and-or post-processing options, such as separation, acidification or ammonia recovery, is recommended. Odour from agricultural AD digestate is generally not as strong as undigested feedstock material. The AD process can also reduce microbial pathogens and the germination capacity of weed seeds found in raw feedstock. Digestate is an important resource that could be processed to replace chemical fertiliser. Research in Teagasc is investigating a wide range of processing technologies to reduce emissions from land spreading and to recover digestate nutrients to replace chemical fertiliser.

Teagasc research at Grange and Johnstown Castle is investigating the sustainable production of AD feedstocks, including the impact of recycling of the resultant digestate as a source of nutrients for plant feedstocks and its fertiliser replacement value. The project includes various plant diversity communities to better understand their availability to the AD system. This project is also pursuing the optimisation of the AD process to improve biogas and biomethane yields. Opportunities to deploy chemical amendments to reduce gaseous emissions from the slurries and digestate, thereby improving biomethane yields during the AD process, are being assessed.

Teagasc is committed to the development of an agri-centric AD industry in Ireland and has invested heavily to resource its research and knowledge transfer capabilities in this area, particularly in the new Teagasc climate action strategy. We have recently recruited two permanent staff in this area. We have invested €1.6 million in a pilot-scale AD biomethane plant in Grange. The Teagasc Grange plant will produce 70 cu. m to 100 cu. m of biogas per hour. The annual gross output of the plant can be specified as roughly 3.42 gigawatt hours, GWh. The biogas will be converted to biomethane, which will be compressed and injected into the gas grid or used to fuel trucks or tractors onsite.

As to the recommendations, the Department of Agriculture, Food and the Marine and Department of the Environment, Climate and Communications-led working group on the development of the national biomethane strategy will be essential in the development of the industry and achievement of the CAP 2023 targets. A prerequisite to the successful development of a biomethane AD sector in Ireland which is agri-centric is that it should be sustainable from an economic, environmental and social perspective, with research gaps on business models and assumptions evident. There is an urgent need to demonstrate agri-centric AD biomethane at scale. The Grange pilot plant will play a key role in achieving this important objective.

To conclude, a prerequisite to the successful deployment of a biomethane industry is that it should be profitable and provide confidence to investors and farmers who decide to provide crop feedstocks on a contractual basis to future biomethane plants. I thank the committee for the opportunity to present this information and welcome any questions the members of the committee would like to ask.