As a carbon mitigation tool, Bioenergy with Carbon Capture and Storage (BECCS) is gaining momentum among scientists and conservationists. But is it effective enough?
Carbon emissions from fossil-fuel use hit a record last year after energy demand grew at its fastest pace in a decade, causing higher oil consumption and more coal-burning across the globe. The International Energy Agency (IEA) recorded 33.1 gigatons of carbon emissions in the global energy sector, up 1.7% from the previous year. While renewable power generation grew last year by about 7%, that was not enough to keep up with the increase in demand.
As global demand for energy continues to surge, emissions from fossil fuel use are expected to further go up unless the world nations start implementing innovative carbon mitigation initiatives.
Negative Emission Technologies (NETs)–the frontier of climate crisis mitigation–might be an effective solution to reduce the global energy sector’s increasing carbon footprint. One of these proposed solutions, Bioenergy with Carbon Capture and Storage (BECCS), is now gaining momentum among scientists and conservationists.
In a nutshell, BECCS is a process in which energy is generated from burning biomass. Carbon dioxide (CO2) produced during the process is captured and sequestered in geological storage units. In simplest terms, the BECCS procedure goes like this: plant thousands of trees which remove CO2 from the atmosphere, burn those trees instead of fossil fuels to produce energy, capture the emitted CO2, and then store it underground. It might sound counterintuitive to burn trees to cut emissions. But the ultimate result of the BECCS is the removal of CO2 from the atmosphere.
If executed efficiently, BECCS will have a significant impact on the energy sector’s carbon footprint. For instance, if the US could sequester CO2 using BECCS, it could reduce emissions by one gigaton of CO2 equivalent (GtCO2eq) annually by 2050. That’s a significant quantity considering the world emitted 36.2 GtCO2eq from fossil fuel combustion in 2017.
The Fifth Assessment Report from the Intergovernmental Panel on Climate Change (IPCC) projected that BECCS could reduce emissions by around 12 GtCO2eq per year by 2100 globally.
BECCS is still in its infancy. As an emerging technology, it raises a lot of questions and challenges that are still being debated. Industrial-scale implementation of this solution needs substantial resources: trees need land, water, and even fertilisers; the energy production process needs new transportation facilities and industrial infrastructure. While the usage of a large volume of water may put pressure on the existing irrigation system, a massive amount of fertilisers may cause serious environmental damage.
A recent study on BECCS states that it would cause food shortage in the future. The world will have to produce 70% extra food by 2050 to keep up with the increasing population, and that means designating more land for agriculture. For a global scale deployment of BECCS, the world needs between 300-600 million hectares of additional land–an area the size of the European Union. If such vast tracts of land are reserved for fast-growing plants as part of BECCS, global agricultural production will be seriously affected.
Large scale cultivation of trees could also bring problems associated with monoculture and biodiversity loss. This argument, however, is often negated by BECCS advocates who argue that the large-scale cultivation of trees can be carried out on degraded lands that were already used for grazing.
The scientific community is still debating about the efficiency and side-effects of BECCS. But in desperate times, as a carbon removal technology, BECCS might prove to be a good bet.