Government scientists have said that the CO2 could be pumped into waterlogged rock formations and empty gas reservoirs underneath the seabed. However, environmental groups say that the proposals are unsafe, unproven, and will divert funds away from research needed to develop renewable energy sources.
The report envisages pumping the CO2 deep in the geological strata beneath the North Sea, possibly in disused gasfields in the southern part, and in oilfields in the northern part. Reservoirs of seawater under the seabed may also be used.
According to the Guardian, the report says that the project, known as CO2 capture and storage (CCS), may need to begin now if the emissions targets are to be achieved. The report says: “With the 60% reduction target for CO2 emissions by 2050, large-scale deployment of CCS may be needed for electricity generation and hydrogen production from about 2020.” The DTI report estimates that the CCS scheme would cost £34-93 to prevent each tonne of CO2 from being emitted, which would correspond to an extra £0.01-0.023/kWh. The DTI report says that this is about the same as the cost of building offshore wind farms and developing tide and wave energy systems.
Critics argue that the scheme would be expensive and probably unworkable. New technology to capture the CO2 produced from the power stations would have to be developed, and an extensive network of underground pipes constructed to carry the gas to the coast. In addition, it would have to be demonstrated that the large bubbles of CO2 that would be created under the seabed would be safe, stable and would not leak.
The report says that more research is needed into legal and long-term safety issues “to ensure the technology is available and cost-effective when it is needed.”