The global community is taking measures to mitigate climate change by decreasing carbon emissions and optimizing energy use efficiency. These include adopting renewable sources of energy, shifting our food systems to decrease deforestation and strengthening natural sinks.
Mitigation efforts can deliver multiple health-related co-benefits – from reduced air pollution and fatal car crashes, to healthier plant-based diets and protected forests.
Carbon Reuse
Carbon reuse, also known as carbon utilization or conversion, involves using captured CO2 to produce low and zero emissions products such as fuels, building materials, plastics and chemical fertilizers. CO2 may also be stored underground geologic formations for permanent storage purposes.
Reusing carbon dioxide can be as straightforward as mixing it with methane (the second most abundant greenhouse gas) through dry reforming to create syngas, which is used to synthesize various fuels and chemicals. Alternatively, carbon dioxide may also be applied towards enhanced oil recovery or food production to increase plant growth while improving crop quality.
As part of their climate plans, many companies and countries have committed to reaching net-zero emissions through carbon capture and storage (CCUS), but carbon removal may also be required to offset any remaining portion that cannot be reduced using other means.
Enhanced Oil Recovery
EOR is a set of technologies used to increase oil extraction beyond traditional depletion methods. Commonly implemented after primary and secondary extraction have failed, EOR typically involves injecting water, chemicals and carbon dioxide into an oil reservoir to stimulate production.
CO2-EOR technology (sometimes referred to as gas injection or CO2-flooding ) is one of the largest applications of carbon dioxide in the US, accounting for more than 100 projects (Oil and Gas Journal 2022). It uses existing CO2 from underground reservoirs back into our atmosphere through recycling.
It is an example of an approach that treats climate change like an emergency and looks for ways to address it amenable to fossil fuel industries. Such an approach would allow them to gradually shift towards more carbon-friendly practices while unlocking billions of barrels of oil along the way, as well as pair nicely with direct air capture (DAC) technology which uses machines to remove CO2 from the air.
Carbon Capture and Storage
Carbon Capture and Storage (CCS) is a pollution control technology which removes CO2 emissions sources or air before they reach the atmosphere, typically through permanent storage underground in certain geological formations, or being used to produce products such as concrete or synthetic fuels. Under certain circumstances such as bioenergy with CCS or direct air capture systems, however, carbon could reemerge when burning off their respective product; otherwise it’s usually permanently sequestered away for storage purposes.
Today there are 41 commercial carbon capture and storage projects worldwide. These facilities separate CO2 produced from natural gas or fossil power plants before transporting and storing it deep underground geological formations for long-term storage. Most of these projects were not intended to address global climate issues; many served purely commercial interests like enhanced oil recovery at oil fields. To meet global climate targets more effectively we will need significantly larger scale CCS technologies which capture even more CO2. Although current technology exists; rapid scaling needs to take place if it is to become part of our long-term energy strategy.
Energy Efficiency
Energy efficiency measures, including reduced energy use in buildings, public and private spaces, power generation and transmission systems and vehicles is crucial to climate change mitigation efforts. Not only can energy savings reduce emissions but they can also save consumers money!
Most carbon dioxide emissions associated with energy come from electricity production, but increasing building and home efficiency can significantly decrease this figure. Agencies including the Departments of Defense, Housing and Urban Development, Transportation, Agriculture and Interior are working on this issue to address it.
Reducing deforestation of forests and other ecosystems that act as natural carbon sinks is another crucial part of climate change mitigation. Such efforts reduce greenhouse gas emissions while providing multiple co-benefits, such as biodiversity conservation and improved water cycles.