Back in 2011 the Committee on Climate Change (CCC) investigated the role that bioenergy could play in meeting the UK’s 2050 carbon emissions target.
Seven years on, the CCC is turning back to academics, industry and research bodies to revisit the evidence, with the Energy Systems Catapult and the Energy Technologies Institute (ETI) submitting a joint response.
By Hannah Evans, Bioenergy lead, Energy Systems Catapult
Bioenergy is one of the largest sources of renewable energy in the UK and is the only renewable source able to produce heat and power as well as liquid and gaseous fuels.
Through its whole energy system analysis and research commissioned as part of its Bioenergy Programme, the ETI has shown that bioenergy could meet around 10 per cent of future UK energy needs and deliver tens of millions of tonnes of net negative CO2 emissions per year in the 2050s, if used in combination with Carbon Capture and Storage (CCS). Achieving this goal will require a mix of residual waste and sustainable biomass feedstocks, and while imported biomass is likely to continue to play an important role in the sector, there is an opportunity to create green growth opportunities through increasing domestic supply.
The ETI and others have carried out analysis on the quantity of UK land which is suitable for growing second generation energy crops (such as Miscanthus, Short Rotation Coppice Willow, and Short Rotation Forestry). This has identified 1.0 – 1.8 Mha (million hectares) that could be made available for bioenergy planting, by the 2050s. This land resource could be released by improving land productivity and reducinge waste throughout the agricultural sector The UK has an opportunity to promote positive change by reshaping incentives for farmers, as we leave the EU’s common agricultural policy.
Planting should be carried out at a steady rate (up to 30-35 thousand hectares per year) to allow the sector to ‘learn by doing’ and manage any wider impacts. In the short-term, planting should target economically marginal land which is poorly suited to other uses. As well as making more productive use of this land, there is increasing evidence that second generation energy crops can deliver additional environmental benefits, including improving water and soil quality, and increasing biodiversity.
In terms of conversion technologies, the ETI’s whole energy system analysis has identified ‘gasification with syngas clean up’, a process by which particulate matter, sulfur compounds, chlorine compounds, nitrogen compounds, unreacted hydrocarbons (tars), and heavy metals are removed. These contaminants can plug up reactors, cause corrosion, poison downstream catalysts, or prevent the plant from complying with environmental permits. Their removal allows us to use the syngas more efficiently, for example in engines. It also allows us to selectively remove and concentrate specific gases, such as carbon dioxide (CO2) removal for compression and transportation by pipeline for either permanent underground storage or for use in enhanced oil recovery. As a scenario resilient technology, largely due to its flexibility – it can generate a range of end products (electricity, heat, liquid and gaseous fuels and chemicals) from a range of biomass and waste feedstocks. Gasification can also be coupled with CCS. Bioenergy with CCS (BECCS) has the potential to deliver ‘negative emissions’ (the net removal of carbon dioxide from the atmosphere), which the ETI’s analysis suggests would significantly lower the cost of meeting the UK’s 2050 climate change targets.
CCS has been commercially deployed in countries including Canada, Norway and the USA and, whilst not deployed yet in the UK, a lot of work has been done to demonstrate its feasibility. The ETI has conducted detailed storage site appraisals, identifying a potential 78 billion tonne storage capacity, whilst its CCS programme has also supported the development of offshore CO2 measurement and monitoring equipment. More broadly, the UK’s expertise in oil and gas, project management and health and safety means it is well placed to exploit the benefits of CCS.
Challenges and Knowledge Gaps
Although there is an opportunity for bioenergy to play an important role in decarbonising the UK energy system, the right market and policy environment is needed if the UK is to realise the greatest benefit from bioenergy.
Planting energy crops is a long-term commitment and there are currently a limited number of buyers within the UK market. Developing other markets for these crops, or rewarding the additional environmental benefits they can bring through agricultural support payments, could help stimulate supply. There are also some land use transitions (notably from permanent grassland) where further work is needed to develop techniques to minimise emissions caused by land use change disturbing stored carbon in soil and plant roots.
The ETI is investing in a commercial scale gasification with syngas clean up power plant to demsontrate the technical and commercial viability of this technology. Similary, the Department for Transport (DfT) is supporting a commercial scale gasification to biomethane plant near Swindon. This dedicated financial support (during construction and in the early years of operation) to scale-up technologies is crucial, as securing debt and equity financing for these riskier projects is very difficult.
More broadly, to bring forward the investment to deliver BECCS in the UK, it is vital that the value of negative emissions is recognised through incentive schemes.
The UK has a great opportunity to develop a sustainable bioenergy energy sector which delivers cost-effective emissions reductions, makes best use of residual (non-recyclable) waste and which can deliver wider environmental benefits. However, developing UK-grown feedstock supplies and resilient technology options requires a clear steer and support from government to provide confidence to farmers, foresters and industry to invest in this sector.
Hannah Evans was part of the the ETI’s Bioenergy Strategy team from 2014-17.
Published: 20 February 2018