Bioenergy with carbon capture and storage, and direct air carbon capture and storage: Examining the evidence on deployment potential and costs in the UK

Context

The Intergovernmental Panel on Climate Change have highlighted that large-scale carbon dioxide removal (CDR) is critical to meeting UNFCCC Paris Agreement targets. This UKERC TPA working paper has been prepared to support the Committee on Climate Change’s advice to the UK government on the implications of the Paris Agreement on its long-term emissions reduction targets. This review addresses two technological CDR solutions: bioenergy with carbon capture and storage (BECCS) and direct air carbon capture and storage (DACCS).

Questions

The overarching questions which this review addresses are:

  1.     What is the potential contribution that these technologies could make to CO2 removal and potentially CO2 emissions reductions to achieve net zero emissions in the UK?
  2.     What are the current and projected costs, globally and in the UK, of these technologies and how plausible are projected cost reductions (including evidence for the benefits to be derived from economies of scale/technology learning)?

Review results

The review revealed that the evidence base for the technical and commercial viability of DACCS is limited and significant uncertainties exist in estimates of technical and economic performance. The range of energy input estimates identified from this review suggest that to capture 1% of the UK’s annual GHG emissions  via DACCS would require 0.5-5.5 TWhe/yr of electricity and 2.8-11.5 TWhth/yr of heat.

The potential deployment of DACCS must therefore be considered in the planning of power and heat systems transitions. Commercial developers of DACCS technologies have suggested that future DACCS costs of £75-95/tCO2 removed are achievable. The academic literature reviewed, however, suggests higher removal costs of £190-540/tCO2.

Viability

The current absence of an incentive for CDR and the relatively low carbon price in the UK render DACCS commercially unviable. Additionally, the lack of CO2 transport and storage (T&S) infrastructure (a pre-requisite to the large-scale deployment of DACCS and BECCS) discourages investment in the technologies. Further work is required to evaluate the technical and economic potential of the archetypes of DACCS technologies being developed within the UK context. The broader implications of DACCS deployment on land and local resources (such as water) also require investigation.

Most of the literature for BECCS has been focused on its potential and cost at the global scale, rather than at the regional scale. BECCS potential in the UK was assessed as between 3 and 60 MtCO2/yr when only considering indigenous biomass, and between 100 and160 MtCO2/yr when considering imports. However, the environmental impacts of UK biomass, potential opposition to bioenergy (such as biomass imports), and a stricter threshold for biomass lifecycle greenhouse gas emissions in regulatory frameworks, could further limit BECCS potential deployment in the UK.

Further study

Further study is needed to determine if the UK technical bioenergy potential is both sustainable and economic. Reviews of BECCS costs indicate values as low as £12/tCO2 and as high as £314/tCO2. Costs in the UK were assessed at between £70 and £130/tCO2 when using local biomass, and between and £150 and £200/tCO2 when using imported biomass.

Whilst the capital cost of BECCS could decrease with learning and/or economies of scale, the potential increase in feedstock cost associated with higher demand and toughening of lifecycle greenhouse gas emissions threshold are key economic challenges facing BECCS.

In the context of a UK bioelectricity plant, CO2 prices between £75 and £210/tCO2 (depending on the feedstock cost) may be required for a plant to achieve economic returns. Though BECCS is a net producer of energy a revenue associated with CO2 removal is also likely to be required for a BECCS plant to be economically viable.

Documents

The project scoping note and working paper can be found here:

Scoping Note

 

UKERC TPA Negative Emissions - V3 Final.pdf

Contacts

The project key contacts are:

Habiba Ahut Daggash

Mathilde Fajardy