Background

In recent years IEAGHG has undertaken a series of studies on the performance and costs of plants incorporating the three leading CO2 capture technologies: post combustion, oxy-combustion and pre-combustion capture. In the time since those studies were undertaken there have been significant technological advances and substantial increases in estimated plant costs. IEAGHG therefore decided to undertake a wholly new study on costs of capture at coal based plants producing the two leading low-carbon energy carriers, namely electricity.

and hydrogen. This study provides a baseline for possible future studies on plants in other countries, plants using other capture processes and capture in industries other than power and hydrogen generation. The study was carried out for IEAGHG by Foster Wheeler.

It should be noted that the focus of this study is to provide an up-to-date technical and economical assessment of coal-fired power and hydrogen plants with CCS. The study does not aim to provide a definitive comparison of different technologies or technology suppliers because such comparisons are strongly influenced by specific local constraints and by market factors, which can be subject to rapid changes.

Key Messages

• This study provides an up-to-date assessment of the performance and costs of coal-based power and hydrogen plants with and without CO2 capture.

• The thermal efficiencies of power plants with CCS based on pulverised coal firing with oxy-combustion or post combustion capture, and IGCC with pre-combustion capture are all around 35% (LHV basis), which is around 9 percentage points lower than a reference pulverised coal plant without capture.

• The levelised cost of electricity is about 92 €/MWh for plants with oxy-combustion or post combustion capture and 115 €/MWh for IGCC plants with pre-combustion capture. This is about 75-125% higher than the reference pulverised coal plant without CCS.

• Costs of CO2 emission avoidance compared to the reference plant are 60-100 €/t.

• The rate of CO2 capture in oxy-combustion and IGCC plants could be increased from 90% to 98%, while reducing the cost per tonne of CO2 emissions avoided by 3%.

• Net CO2 emissions of a plant with post combustion capture could be reduced to zero by co-firing 10% biomass (on a carbon basis), without increasing the cost per tonne of CO2 avoided, depending on the price of biomass.

• The raw water requirements of the pulverised coal power plants with CCS could be reduced to near zero by using seawater or air cooling. For the ambient conditions considered in this study this would have little impact on the efficiency (<1 percentage point) and capital cost (<2%).

• The efficiency of producing hydrogen by coal gasification with CCS would be 58% LHV basis (65% HHV basis) and the levelised cost of production would be 16.1 €/GJ LHV basis (13.6 €/GJ HHV basis).