Key benefits

Since the USDOE program, there have been important changes to economic and industry drivers which increase the advantage of DICE: carbon penalties, the need to support a step increase in intermittent renewables, changes to the structure of the electricity supply industry, energy security issues, the ability to be capture ready and capture efficient, and the shortage of cooling water.

Overall, DICE now promises a considerably more efficient, nimble and adaptable generation technology than is possible with pulverised coal-fired steam plants.

Key benefits of DICE

  • A step reduction in CO2 intensity of around 20–35% for black coal, and 30–50% for brown coals, and doubling of the CO2 benefit of biochars.
  • High efficiency at small unit size, which allows smaller and easier investment steps.
  • Lower capital cost at $1200–2000/kW (about half that of supercritical pulverised coal plants) which, together with tolerance to load changes, makes stop-start operation for peak and backup duty a practical and economic option for coal-based generation. DICE should be economic for base load, peaking and backup duties to support renewables, and changing electricity markets. Unlike natural gas turbines, this flexibility can be provided without losing efficiency or increased maintenance.
  • Allowing ultra-efficient use of opportunity biofuels, particularly biochar, to further reduce the net carbon footprint. For example, MRC could be co-fuelled with char to provide a sweetener for char, by improving its ignition and combustion.
  • Providing an enabling technology for CCS by enabling bolt-on integration of CO2 capture, with a substantially lower energy penalty, and without significant power output de-rating, compared to existing coal power plants.
  • Maintaining rating under hot, arid and high altitude conditions, and with low overall water use.

A solution to the water dilemma

DICE uses no water at the power plant, and only a small amount of water for MRC preparation - about 1/10th of that of a conventional steam power plant. While dry cooling can be used by conventional steam plants, this increases the plant capital cost by around 15%, and decreases efficiency by around 2% points which increases CO2 emissions.

For dry cooled steam plants an additional 1 tonne of CO2 is emitted per 30 tonnes of water saved. Dry cooling also gives a 15% increase in plant capital cost.

The water issue is of urgent concern for India and China.

Thermal power generation versus water scarcity by province in China, 2010 and 2030