Microbial electrolysis carbon capture (MECC) is a carbon capture technique using microbial electrolysis cells during wastewater treatment. MECC results in net negative carbon emission wastewater treatment by removal of carbon dioxide (CO2) during the treatment process in the form of calcite (CaCO3), and production of profitable H2 gas.
Anthropogenic carbon dioxide emissions contribute to significant regional climate change due to the compound's contribution to the greenhouse gas effect in the atmosphere. Most mitigation goals to remove CO2 from the atmosphere are based on high levels of CO2 produced by fossil fuel combustion as a basis for energy production. The use of fossil fuels emits CO2 and other toxic compounds such as SOx and NOx in the process of combustion. Economic growth is reliant on energy production for transportation and industrial production of goods and services, the amount of CO2 emitted is predicted to continue to increase in the foreseeable future.
Wastewater processing reflects a small percentage of greenhouse gas emissions. Currently, wastewater treatment consumes "3% of total electricity within the U.S."[1] At least 12 trillion gallons of wastewater are treated in the United States alone per year, which contributes to 1.5% of global greenhouse gas emissions.[1] Microbial electrolysis carbon capture (MECC) is a process that contributes to sustainable energy practice in both private and public sectors. MECC takes advantage of properties inherent to wastewater, such as organic content, to remove carbon dioxide and produce calcite precipitate and hydrogen gas.