The World Coal Institute noted that in 2003 the high cost of carbon capture and storage (estimates of US$ 150-220 per tonne of carbon, $40-60/t CO2 – 3.5 to 5.5 c/kWh relative to coal burned at 35% thermal efficiency) made the option uneconomic.
But a lot of work is being done to improve the economic viability of it, and the US Dept of Energy (DOE) was funding R&D with a view to reducing the cost of carbon sequestered to US$ 10/tC (equivalent to 0.25 c/kWh) or less by 2008, and by 2012 to reduce the cost of carbon capture and sequestration to a 10% increment on electricity generation costs.
These targets now seem very unrealistic.
A 2000 US study put the cost of CO2 capture for IGCC plants at 1.7 c/kWh, with an energy penalty 14.6% and a cost of avoided CO2 of $26/t ($96/t C).
By 2010 this was expected to improve to 1.0 c/kWh, 9% energy penalty and avoided CO2 cost of $18/t ($66/t C), but these numbers now seem unduly optimistic.
Figures from IPCC Mitigation working group in 2005 for IGCC put capture and sequestration cost at 1.0-3.2 c/kWh, thus increasing electricity cost for IGCC by 21-78% to 5.5 to 9.1 c/kWh.
The energy penalty in that was 14-25% and the mitigation cost $14-53/t CO2 ($51-200/tC) avoided.
These figures included up to $5 per tonne CO2 for transport and up to $8.30 /t CO2 for geological sequestration.
In 2009 the OECD’s International Energy Agency (IEA) estimated for CCS $40-90/t CO2 but foresees $35-60/t by 2030, and McKinsey & Company estimated €60-90/t reducing to €30-45/t after 2030.
ExxonMobil is proposing that, where amine scrubbing is employed, the whole power plant exhaust is directed to a carbonate fuel cell which will generate over 20% more power overall, instead of costing 10% of the power due to diversion of steam. The CO2 still needs to be disposed of.
In Australia the $240 million Callide Oxyfuel project in Queensland aims to demonstrate oxyfuel capture technology retrofitted to a 30 MW unit of an existing coal-fired power plant and to research how it might be applied to new power stations.
The plant was commissioned in 2012 and was to run for an extended test period until November 2014.
By mid-2013 the project had demonstrated CO2 capture rates from the oxyfuel flue gas stream to the CO2 capture plant in excess of 85%, and produced a high quality CO2 product suitable for geological storage.
The project achieved more than 10,000 hours of oxy-combustion and more than 5,000 hours of carbon capture from Callide A.
The plant was then decommissioned.
CS Energy led the project and is working closely with an international team of partners including IHI Corporation (Japan), J-Power (Japan), Mitsui & Company (Japan), and Xstrata Coal.
Also in Australia the $150 million Delta Post Combustion Capture project hosted at Delta’s 1320 MWe Vales Point coal-fired power station in NSW aimed to demonstrate capture and sequestration of 100,000 t/yr of CO2 by 2015.
However, after massive losses the plant was sold for a token sum in November 2015, with no mention of the CCS project.
Both Australian projects were funded by federal and state governments and the coal industry.
Press link for more: World.nuclear.org