Bioenergy with Carbon Capture and Storage (BECCS)

BECCS Process Overview

What is BECCS?`

Another major negative emissions technology is bioenergy with carbon capture and storage (BECCS). BECCS facilities can produce energy to power the grid from the combustion of biomass like grass or corn. Combustion of biomass, like fossil fuel combustion, produces heat that transfers to water making steam that then flows over turbine blades and turns them, generating electricity. BECCS also remove carbon from the atmosphere as there would be a carbon capture setup for the emissions, and then the carbon would be transported and pumped into geologic rock formations where it will be trapped ideally forever.

How is this better than an already existing natural gas power plant with CCS?

It's not just a reduction of our carbon emissions like fossil fuel technology is but it's in fact a removal. The biomass are plants growing on land and absorbing CO2 from the atmosphere. When they are burned, the CO2 gets separated and pumped into the ground. Carbon is overall being taken from the atmosphere and then put back into the ground. In a coal or natural gas CCS plant, carbon is taken out of the ground and combusted so that even with a perfect 100% carbon capture rate, the overall result is at best a reduction in emissions but not a removal. Also, when's the last time you heard of 100% efficiency?

BECCS are key to most Integrated Assessment plans created by the IPCC to meet any temperature rise limits of 2 degrees Celsius [1]. This is because BECCS as a technology not only saves the environment but also produces potentially profitable carbon neutral electricity. The switch to a green grid is important socially too as many people won’t seriously consider green individual choices like the switch to an EV until there is green electricity and they see leaders of energy like electric utilities making these changes.

What is the impact of this solution?

There has been discussion about BECCS at the country level, where one analysis stated the United States should provide a net negative 60 GtCO2 eq from 2010-2100 to keep on track with our goals of reducing temperature rise to below 2 degrees Celsius [1]. The yearly amounts of net negative emissions would gradually increase but this averages to 0.67 GtCO2eq per year. This is a ballpark figure that we must decide how to approach.

There are about 1400 fossil fuel electric power plants in the United States according to the Energy Information Administration [2]. We propose to phase out just 350 or 25% of these for BECCS facilities. Models have shown potential for yearly negative CO2eq emissions ranging from 1.0 to 1.52 Mt for a 250 MW BECCS plant [3]. We assume technological increases will allow us to achieve a 1.5 Mt negative CO2 emission per plant. For the 350 plant scale we propose, this will result in 0.53 GtCO2eq per year removal.

What is the scale and implementation?

The scale of BECCS is often proposed to be large as BECCS synergizes with renewables by being the flexible power generation base load. The technology does have some potential issues that must be addressed and so our scale is fairly conservative. Researcher Christopher B. Field has called BECCS a “truly massive use of a technology with little real-world experience and poorly known economics” [4].

Economic estimates vary but the cost of CO2 avoided is in the typical range of $60-$120 per tonne [3]. To compete with natural gas, there would need to be a carbon tax about double this avoided range and that is a policy we propose. The technology readiness level of BECCS is 4-6 which represents it being in the early demonstration phase [5]. Although it is still in this phase, there are some BECCS facilities in the U.S. and around the world that are operating at a small scale.

BECCS Projects Around the Globe

What are the issues with BECCS?

Issues with BECCS implementation include the large social and public acceptance fear that climate scientists would prioritize the environment over agriculture production. Of course, there's already a large excess of food being produced that is not being effectively distributed or just being wasted. Specifically, food waste is 30-40% of food supply in the U.S [6]. There should be no issue then about the United States ability to produce food and biomass. However, the amount of feedstock required to sequester anything is fairly large.

This is in part due to large global supply chains needed for BECCS which will be its own political issue with dealing with other countries and independent certification of carbon being sequestered successfully. This is also due to large carbon losses in the BECCS processing chain from things like gasification and even transportation of the biomass.

One study stated it would take 200 million hectares (about half of the U.S. cropland area) of switchgrass to remove 3.7 GtCO2 per year [7]. For our proposed BECCS scale this will be 28 million hectares of switchgrass. Of course, there needs to be consideration of things like biodiversity of ecosystems, effects on the regional freshwater supply, and fertilizer usage.

One option to consider is that we can use various types of biomass as feedstock, including things like forest and agriculture residues to crops like corn.

Various Biomass Pathways

Timeline?

As this scale involves a significant investment into biomass production for BECCS and the technology is still being implemented at the small scale level, we believe that this solution can be implemented within the next 10-15 years.

What policies should we implement?

Policy wise, the U.S. government must step in to assist with land rights to grow biomass and also potentially create international agreements to set up global supply chains. They must also fund further R&D efforts into the BECCS technology primarily with the goal of reducing processing carbon losses. Finally they must price carbon emissions around $120-$200 per tonne to make BECCS viable and even competitive with natural gas. We only have one planet, let’s work together to save it. Get involved with your local climate activist group and also inform your friends and family about these climate change issues and the BECCS (the best) part of the solution. BECCS will be key to preventing climate disaster!

References

• (1)Galik, C. S. A Continuing Need to Revisit BECCS and Its Potential. Nat. Clim. Chang. 2020, 10 (1), 2–3.

• (2)SAS Output https://www.eia.gov/electricity/annual/html/epa_04_01.html (accessed Dec 6, 2020).

• (3)Emenike, O.; Michailos, S.; Finney, K. N.; Hughes, K. J.; Ingham, D.; Pourkashanian, M. Initial Techno-Economic Screening of BECCS Technologies in Power Generation for a Range of Biomass Feedstock. Sustain. Energy Technol. Assessments 2020, 40 (100743), 100743.

• (4)Field, C. B.; Mach, K. J. Rightsizing Carbon Dioxide Removal. Science 2017, 356 (6339), 706–707.

• (5)Sikdar, S.; Princiotta, F. Advances in Carbon Management Technologies: Carbon Removal, Renewable and Nuclear Energy, Volume 1; CRC Press: Boca Raton, FL, 2020.

• (6)Food waste FAQs https://www.usda.gov/foodwaste/faqs (accessed Dec 6, 2020).

• (7)Brack, D.; King, R. Managing Land-Based CDR: BECCS, Forests and Carbon Sequestration: Managing Land-Based CDR. Glob. Policy 2020. https://doi.org/10.1111/1758-5899.12827.

• Kemper, J. Biomass with carbon capture and storage (BECCS/Bio-CCS) https://ieaghg.org/docs/General_Docs/IEAGHG_Presentations/2017-03-10_Bioenergy_lecture_2_Read-Only.pdf (accessed Dec 6, 2020). (All images)