A recent techno-economic study of the Origen Power process published in Applied Energy (Hanak et al, 2017) indicates that the process can economically generate electricity in a way that removes carbon dioxide from the atmosphere – without a carbon price.

The Origen Power process supplies natural gas to a fuel cell, where about half of the chemical energy in the natural gas is converted into electricity. The remainder is converted into heat, which is used in a lime kiln to thermally decompose limestone into lime and carbon dioxide. The process is configured in such a way that all the carbon dioxide generated – both from the fuel cell and the lime kiln – is pure, enabling it to be either used industrially or sequestered at low cost.

The lime that is produced can be used industrially and, in being used, draws carbon dioxide out of the air. Overall, the process is carbon-negative – there is less carbon dioxide in the air at the end of the process than there was at the outset.

The study, led by Dr Dawid Hanak of Cranfield University, modelled the Origen Power process at a 25MW-scale using AspenPlus™ software. At that scale, the process will generate (on a daily basis):

  • (i) 409MWh of electricity (η = 47.7LHV)
  • (ii) 307 tonnes of lime
  • (iii) 362 tonnes of pure CO2 (>99%).
  • (iv) If the pure CO2 is sequestered, then the lime will remove 190 tonnes of CO2 from the air (net).
  • If all the costs of the process are loaded onto the sale of electricity (that is with no revenue from the other products) then the levelised cost of electricity is £69.1 per MWh. If all the costs are loaded onto the removal of CO2 from the air, a carbon price of £149.0 per tonne of CO2 would be required.

    If the electricity and lime are sold at wholesale market prices (£42 per MWh of electricity and £60 per tonne of lime) then the costs are covered without a carbon price – even as it withdraws CO2 from the air.

    For more information, please contact Tim Kruger at tim@origenpower.com