California can hit its goal of going carbon neutral by 2045 if it pulls emissions out of the air and slashes greenhouse gases from farming, landfills and other sources, according to a federal study released yesterday.
The nation’s most populous state needs to remove 125 million tons of carbon emissions per year from the atmosphere, roughly equivalent of removing 26 million cars from its roads annually, said an analysis by the Lawrence Livermore National Laboratory.
The state has adopted numerous policies to cut its emissions, but those won’t be enough. Pollution sources that are tougher to reach, including those in the transportation, agriculture and industrial sectors, will have to be addressed more aggressively, the analysis said. State leaders will also have to race into the frontier of climate action: removing CO2 from the air.
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“Without CO2 removal, reaching our carbon neutrality goal will be slower, more difficult and costly,” Sarah Baker, a chemist and a lead author of the report, said in a statement. “While there are no silver bullets, we have evaluated strategies that rely on many existing technologies and resources, creating a CO2 removal blueprint that can be replicated.”
A 2018 executive order from then-Gov. Jerry Brown (D) requires the state to reach carbon neutrality by 2045 and maintain net negative emissions thereafter. If the state accomplishes the aim, the analysis said, it can show other states and countries how to remove carbon from the atmosphere.
The analysis recommended three solutions. It said the Golden State should capture and store carbon using better land management, convert biomass waste to fuels and store the associated greenhouse gas pollution, and remove carbon from the air using machines that are not yet widely available.
It will cost about $10 billion per year—about 0.4% of the value of goods and services produced annually by the Golden State.
Removing carbon from the atmosphere, or direct air capture, is a cornerstone of the report.
“It is more expensive than most negative emissions options for California but has a nearly unlimited technical capacity,” the analysis said.
The technology involves absorbing carbon into a solvent or onto a solid material. Then that carbon is released into a stream for storage. The process is energy intensive, the report said, and using solar or wind to power the system would mean taking up swaths of land. For that reason, the report said, it focused on direct air capture using solvent-based systems powered by natural gas with CO2 capture and systems powered by geothermal energy.
Improving how the state manages its landscape is also a top strategy, the report said. Natural and working lands cover over 90% of California. That acreage includes farmland, rangeland, forests, woodlands, wetlands, coastal areas, grasslands, shrub land, riparian areas and urban green space.
“These lands can clearly act as carbon sinks given the living plant matter they host, but they can also act as carbon sources when they burn, are cultivated intensively using conventional fertilization and tilling practices, or are converted from their natural state to another land use,” the study said.
The analysis suggested changes to forest management: adding trees to sites burned by wildfire, rotating crops, and turning areas that have been used for growing corn and other pastures into wetlands.
Changing how the state deals with waste is another solution, the report said. That includes agriculture residue, trash from cities and counties, gaseous waste from landfills and anaerobic digesters, sawmill residue, and shrubs and chaparral.
Currently, most of the carbon from biomass is produced as the biomass decays, burns or is used to produce energy at power plants that vent carbon emissions.
The technology with the lowest cost and the greatest potential for negating emissions is gasification of solid biomass to produce hydrogen. Converting biomass to hydrogen “generates the most recoverable CO2, since nearly all of the carbon in the biomass can be captured during processing.”
The report also looked at producing liquid fuels from biomass. Those could help displace fossil fuels from air transportation and heavy industry.
More research is needed to make the solutions work for California, the report said. Waste biomass conversion and direct air capture will require “a broad range of technologies.” While some of those are ready now, others are in early development and likely are more costly today than they will be when better developed.
“Learning is a critical aspect of reducing the cost of new technologies, which requires deployment in the field,” it said.
Reprinted from Climatewire with permission from E&E News. E&E provides daily coverage of essential energy and environmental news at www.eenews.net.