Creating Clean Coal: Carbon Capture and Storage, Integrated Gasification Combined Cycle
Conversations centering on climate change focus heavily on renewable energy sources, with solar and wind energy dominating the priority list of solutions. But there are other options available that work by upgrading current systems to harness the power of coal without heavy carbon dioxide emissions: carbon capture and storage (CCS) and integrated gasification combined cycle (IGCC) systems.
Carbon Capture and Storage
Simply put, CCS is integrated into fossil fuel power plants, capturing carbon dioxide emissions so that they can be transported to a storage site, preventing them from entering into the atmosphere. Perhaps one of the simplest means of utilizing the infrastructure already in place, CCS turns carbon-emission-heavy fuel sources into a clean form of renewable energy, acting as a simpler means of combating climate change.
The first stage of this process involves capturing the CO2 and compressing it for storage. Methods vary, although for coal, CO2 is often captured post-combustion. From here, the emissions are pumped through a pipeline to a storage site deep underground, about 7,000 feet below the surface. In cases where pipelines are impossible, CO2 can also be transported to a storage site via ship.
CCS has an added benefit for the oil industry: injecting CO2 into dwindling oil fields forces the oil to the surface, making extraction easier. Ultimately, CCS reduces emissions by up to 90%; for reference, reducing 90% of emissions from one coal plant has the same environmental benefits as eliminating 300,000 homes from the grid.
Integrated Gasification Combined Cycle
Although the term “clean coal” is often met with a snicker, IGCC technology is a promising means of making the idea of clean coal an environmentally friendly reality. Essentially, the system turns coal into gas, making it possible to remove all impurities, or “filter” it, including extracting sulfur and mercury.
The gasification and cleansing process produces steam, which in turn fuels the overall operation of the plant, including the gasification and cleansing process. The clean coal gas is then sent to a combustion turbine generator to create electricity. The technology incorporates several ideas into one complex cycle, constantly feeding itself without heavy carbon dioxide emissions or pumping sulfur and mercury into the atmosphere.
These two exceptionally viable options for combating global warming and creating a true “clean coal” plant shouldn’t be ignored. Despite the initial upfront cost, current plants utilizing these methods report high levels of success and dropping costs over the lifetime of the operation.