What is CCS?
Carbon capture and storage (CCS), which is sometimes called carbon capture and sequestration, prevents large amounts of carbon dioxide (CO2) from being released into the atmosphere. The technology involves capturing CO2 produced by large industrial plants, compressing it for transportation and then injecting it deep into a rock formation at a carefully selected and safe site, where it is permanently stored.
Because CCS can achieve significant CO2 emission reductions, it is considered a key option within the portfolio of approaches required to reduce greenhouse gas emissions.
CCS technology involves three major steps:
The separation of CO2 from other gases produced at large industrial process facilities such as coal and natural gas power plants, oil and gas plants, steel mills, cement plants, etc.
Once separated, the CO2 is compressed and transported via pipelines, trucks, ships or other methods to a suitable site for geological storage.
CO2 is injected into deep underground rock formations, often at depths of one kilometre or more.
Why do we need CCS?
The world is facing a climate challenge. To avoid dangerous climate change, the global average temperature rise must be capped at 2oC relative to pre-industrial times. To achieve this, we are dependent on a revolutionary scale of CO2 mitigation that could see CCS contribute between 15 and 55 per cent of the required abatement to the year 2100 (2005, IPCC Special Report).
Electricity sourced from fossil fuels accounts for more than 40 per cent of the world’s energy-related CO2 emissions (2011, IEA CO2 Emissions from Fuel Combustion).
Another 25 per cent of emissions come from large–scale industrial processes such as iron and steel production, cement making, natural gas processing and petroleum refining. Demand for fossil fuels is increasing, especially in developing countries, where a significant percentage of the population has no access to electricity.
CCS is a viable option—in some cases, it is the only viable option—for reducing emissions from such large–scale sources. Further, it has the potential to help reduce to almost zero the emissions released into the atmosphere from power plants and industrial plants.
A portfolio approach
Renewables, like CCS, are an important part of a sustainable clean energy portfolio. However, given the large, easily accessible, low-cost reserves of fossil fuels available, they will continue to be used to generate power and support industry for many decades to come.
The Global CCS Institute advocates for CCS as one option that can stem CO2 emissions as the world transitions to a new energy future.