The transportation fuels ethanol and 1-propanol are produced from cellulosic biomass and sold into the California and Oregon gasoline markets. Federal and state subsidies for renewable fuels derived from cellulosic biomass greatly increase their sale price. Both fuels are EPA-approved for use in alcohol/gasoline blends.
There's good BECCS, bad BECCS and really, really bad BECCS.
Good BECCS uses waste biomass to produce fuels and CO2. The waste biomass comes from food production facilities and crop residue. Crop residue is the leftover biomass remaining on fields after harvest. Between 15% and over 50% of this residue can be used as feedstock to produce bioenergy. In good BECCS systems, the biomass conversion process also produces CO2 as a clean, easy to capture gas stream.
Net zero refers to the point when civilization emits zero net greenhouse gases. To achieve this, you start by replacing fossil fuels with renewable energy sources like wind and solar. However, even at net zero, some fossil fuels may still be used, and other greenhouse gases, such as methane, will still be released. This is where BECCS comes in: it supports renewable energy efforts and ensures sufficient CO2 capture and storage to offset the greenhouse gas emissions from fossil fuels and other sources.
According to the United Nations IPCC 6th Assessment Report, released in 2023, net zero will be achieved between 2065 and 2075. The report produced five Illustrative Mitigation Pathways (IMPs) that can achieve net zero. All five pathways require BECCS, but three of these have been shown to have sustainability problems. The two viable pathways are IMP-Ren, which achieves net zero in 2065, and IMP-SP, which achieves it in 2075.
Carbon capture and storage does work and has been used in the U.S. for several decades. We have over 4,500 miles of CO2 pipelines that transport CO2 from naturally occurring sources and industrial plants, across the country. These industries produce clean, easy-to-capture CO2 streams.
Currently, this CO2 is used for enhanced oil recovery. Most of this CO2 is still permanently sequestered in the underground formations. The remaining CO2 can be stored permanently by capping the nearby wells instead of using those wells to produce fossil fuels.
Biomass can contain over 40% oxygen and much of this oxygen comes out as CO2 when biomass is depolymerized or undergoes fermentation. This CO2 comes out as a clean gas stream that contains no nitrogen and is easy to capture.
On the other hand, burning biomass to produce power creates a gas stream that has a small amount of CO2 contained in a large amount of nitrogen gas. Separating the CO2 from this type of stream has proven to be difficult and has not achieved commercial viability. Power plants that burn fossil fuels have this same problem when it comes to capturing CO2.
Direct air capture faces two primary challenges. First, it is an energy sink because it requires large amounts of energy without producing any usable energy in return. Second, it cannot currently make a profit given today's low CO2 pricing, making it a financial sink as well.
Good BECCS, on the other hand, produces energy and CO2 while being profitable. It's also versatile and can make transportation fuels or work in support of solar and wind power as necessary while providing income that can be used to scale BECCS deployment.