Blog: Finding the win-win for BECCS as we move to net zero

01 Jul 2020

There has been a growing interest in the use of bioenergy with carbon capture and storage (BECCS) to achieve a net reduction in greenhouse gases. BECCS involves the combustion of biomass to generate energy, using trees and grasses grown on both agricultural land and marginal land unsuitable for food crops. The resulting CO2 emissions are captured, compressed, and transported to suitable underground storage sites.

BECCS is an example of a Negative Emission Technology (NET), with others including direct capture of CO­2 from the air, afforestation and carbon capture by trees, and pulverisation of rocks to enhance the natural weathering process and CO2 uptake. These are controversial technologies because they are largely untested at scale and because we have a limited understanding of their wider impacts on society and the environment.

BECCS and ecosystem services

Achieving the Paris Agreement targets requires net zero emissions. The UK, along with other nations, plans to deploy NETs to achieve a net zero economy by 2050. BECCS features heavily in the net zero energy scenarios, estimated to be as high as 15 GW (capturing 67 Mt of CO2 per year) by the UK Committee on Climate Change. However, the models used to generate BECCS scenarios don’t quantify the environmental and social implications of BECCS and rarely consider the environment. One way to address this question is to assess the consequences of BECCS on a basket of ecosystems services – the benefits derived from the environment that makes human life possible and worth living.

In a new publication, Donnison et al. (2020)1 show that positive ecosystem service benefits of BECCS using domestic biomass do exist. Depending on location these can include increased flood protection and carbon sequestration, with Drax identified as one of the most positive UK sites for the delivery of ecosystem service benefits. However, these benefits decline with size with 1 GW BECCS being significantly less beneficial to the environment than 500 MW, suggesting that future BECCS requires site-specific ecosystem service valuations to assess trade-offs and co-benefits of this NET and that smaller power plants are preferred over large infrastructures.

PI Professor Gail Taylor said “the novelty of this study is that for the first time we have managed to quantify the impact of BECCS at a regional scale, on the environment – showing perhaps surprisingly that BECCS can have significant positive impacts because long-lived trees are good for soil carbon and flood protection. However, this net benefit depends very much on where the BECCS power station is sited and consistently, in our study, declined as the capacity of the power station increased.  These are very significant findings for policy makers if BECCS, as predicted, is to play a big role in the UK strategy to get to net zero by 2050”.

This research was funded by UKRI, NERC project “ADdressing the Value of Energy and Nature Together (ADVENT)” that’s is part of the UK Energy Research Center (UKERC) research program

1 Donnison C, Holland RA, Hastings A, Armstrong L-M, Eigenbrod F, Taylor G Bioenergy wit carbon capture and storage (BECCS): Finding the win-wins for energy, negative emissions and ecosystem services – size matter GCB Bioenergy. 2020:00:1-19. https://doi.org/101111/gcbb.12695.

Contact: Gail Taylor, gtaylor@ucdavis.edu; g.taylor@soton.ac.uk; +15309026013, +447885031007

Caspar Donnison, cdonnison@ucdavis.edu; c.donnison@soton.ac.uk