The Government’s vision for a new “agri-centric and farmer-led” anaerobic digestion (AD) industry remains some way off.

Under Climate Action Plan targets, the equivalent of 10% of Ireland’s natural gas must be supplied by biomethane by 2030, requiring the rapid development of a network of new AD plants.

Last week, the Government launched a four-week online public consultation on the draft national biomethane strategy, a product of a year’s work by a working group involving all key Government departments and stakeholders.

The industry had high hopes that the strategy would provide a clear roadmap as to how the 2030 biomethane target would be achieved, giving some confidence to those considering, interested in, or progressing with AD projects.

While it touches on some key issues, like funding, sustainability, planning and community engagement, the strategy reads more like an explainer on AD than a roadmap on how to build a biomethane industry.

As this is only the draft, some of the key issues may yet be addressed in the final version. However, with a commitment to release the final strategy by the end of March this year, it is difficult to see how the required level of detail will be fleshed out by then. Nevertheless, the draft does offer some useful insights into the Government’s vision for this new industry.

What is the vision?

The Government’s vision is that by 2030, Ireland will have developed a sustainable AD sector of scale, producing biomethane gas to be used to decarbonise the energy sector. In doing so, it will create a credible and sustainable diversification option for Ireland’s rural economy via the AD plants, but also through new green biorefinery systems.

Size of AD plants

The consultation explores three scenarios for AD development and asks consultees to rate which one is optimal for Ireland. The first, “widespread deployment”, scenario looks at smaller, farm-scale AD plants, with an annual feedstock requirement of 25,000t. Two-hundred and fifty of these AD plants would be needed by 2030, which would likely be spread out across the country, similar to Northern Ireland’s model. The working group states that this model would involve a greater number of farmers in the biomethane industry, which may also assist with community buy-in. However, this model would be the most expensive option for the taxpayer and likely wouldn’t meet our 2030 target.

The second, “current policies only”, scenario examines the development of 90 larger AD plants with a feedstock requirement ranging from 40,000t to 60,000t. This would represent the lowest cost to the taxpayer, as this scenario was modelled with no support provided. The working group states that companies which can afford the “green premium” for biomethane will pay it, but some sectors risk being priced out of the market. While this scenario will result in some level of biomethane production in Ireland, it is very unlikely to achieve the 2030 target, it states. The final, “economic deployment”, scenario considers a mix of 140 larger and smaller plants, with feedstock requirements ranging from 25,000t to 60,000t. However, the work group notes that most plants in this scenario would be on the larger side, likely 50,000t or more. This is seen as the most economical and cost-efficient approach for developing a biomethane industry, though it will result in less involvement from the farming community.

Farmer feedstock

While food waste may be considered the optimal feedstock for AD, there isn’t enough available to meet the required scale. Instead, the Government envisages that the majority of AD plants will need to be supplied with grass silage and slurry from farmers. The report states that, at a national level, by 2030 a total land area of around 300,000ac will be needed to produce the silage to feed the AD industry. The report makes no reference to using cereals or other crops for biomethane production, although these are set to be key feedstocks in projects already planned for Ireland. Slurry from 1.3m cattle will also be needed by 2030, approximately 20% of all winter cattle slurry produced in Ireland.

As a key aim of biomethane is to reduce agriculture’s emissions and improve environmental sustainability, the working group states that producing feedstocks can’t lead to further farm intensification. The strategy states that in order to meet EU biomethane sustainability requirements, silage should be made with minimal chemical fertilisers to meet the necessary emission savings. No indication of feedstock prices or contract arrangements are provided in the strategy.

Financial support

Biomethane gas is more expensive than natural gas. How this price gap is bridged by Government support will determine if a biomethane sector develops at scale or not. Across Europe, ongoing operational support schemes, such as a feed-in tariffs or price guarantees, have been central to establishing an AD industry. Our own Irish Ministers have in the past committed to providing capital grants for AD plants and an obligation scheme.

However, the strategy gives no detail on proposed supports and how they might work. The strategy does go to lengths to stress that the amount of support required will be dependent on the type and size of the AD plant, as the cost of biomethane production varies accordingly. The strategy outlines that larger, gas grid-connected plants can produce biomethane at a significantly cheaper price than smaller-scale, off-grid plants. According to analysis by the working group, they believe biomethane can be produced for 16-22c/kWh for smaller plants (25,000t), 12-15c/kWh for larger plants (40,000-60,000t) and for 12c/kWh for larger plants. Based on current natural gas prices, a green premium of either 9-15c/kWh, 5-8c/kWh, or 5c/kWh would be needed for the three respective plant sizes to make them economically viable. The consultation asks what kind of support is needed to bridge this gap, whether it be ongoing operational support, capital grants, or feedstock support. However, for such a critical question, no detail is provided to the consultees on what these types of support entail, or how they would work. Regardless of what support is introduced, biomethane projects will have to sign up to a new best practice biomethane charter in order to protect against unintended negative consequences, the strategy states.

Planning permission

Lengthy timelines, confusion and inconsistent decisions being reached by different local authorities on AD planning applications, due to varying levels of understanding around the technology, were outlined as problems by the working group. In response, the Government will develop a new standardised code of practice for local authorities to follow when assessing an AD planning application. However, no further information or timelines were provided.

Environmental Protection Agency

The working group states that AD plants will require some form of permitting from either the EPA or the Local Authority. Currently, this varies between a waste permit (from the Local Authority), a waste licence, or an industrial emissions licence (from the EPA). It now appears almost certain that an EPA waste licence will be needed for agricultural biomethane plants processing over 10,000t of slurry. This changes the nature of the project, adding substantial cost, complexity and challenges to gaining public acceptance of agricultural projects. An EPA licence can take up to 15-24 months to process, costing in excess of €70,000, and is typically only applied for after planning permission is secured. The EPA, which was consulted on the strategy, made it clear that further resourcing is required to handle this expected workload.

Online portal

To reduce development times and avoid delays, the working group proposes to develop an online portal that will outline the exact requirements for a project, depending on scale, feedstock type and tonnages. No further information or timelines were given on this.

Gas grid

Perhaps the most substantial comments by the working group, however, concern the gas grid connection process. Under Gas Networks Ireland’s (GNI) connection process, to connect AD plants directly to the gas grid, developers are required to pay only 30% of the estimated costs for the connection, which involves a new gas pipeline and a grid entry unit. However, developers must also place a financial bond for the remaining 70% as security to GNI for several years. Given that the cost of connecting AD plants to the grid in Ireland has been shown to be up to three times more expensive than in neighbouring countries, this 70% financial bond requirement is making some projects unviable. As GNI needs to deliver a significant amount of infrastructure over the next six years to support new electricity generators in Ireland, the strategy suggests a need to review the status of contestable works that can be carried out by developers, to ensure AD developments are not hampered by grid connection delays. Contestable gas grid connections would allow the developer to use contractors for construction works, with GNI performing the final connection to the gas network. This approach could increase competition and lower grid connection costs.


The strategy also explores the potential of collocating AD plants with green biorefineries. These facilities would process materials such as grass, silage and other forages, extracting valuable compounds and substrates, including proteins and fibres. As part of its commitment to growing the bioeconomy, the Government plans to invest up to €30m in biorefinery piloting and demonstration facilities over the next two to three years.


While this draft strategy has many areas for improvement, it represents a starting point. Participation in the consultation process is crucial, as the actions outlined in the strategy will be incorporated into future versions of the Climate Action Plan. The public is invited to share their input through an online survey consisting of 11 questions.

You can take the survey here.

The author Stephen Robb is currently involved in a family/community proposal for an anaerobic digestion facility in Co Donegal.