Flexible operation of gas-fired power plants

Existing gas power capacity is not always optimised for the flexibility requirements of systems with higher shares of variable renewables. Growing shares of renewables in the power system challenges conventional operational practices of these plants.

Coal-fired power

Innovation efforts should focus on boosting overall full-load efficiency and plant flexibility, for example by increasing ramping speed (the pace at which generation can be increased to meet demand) and part-load efficiencies. Flexibility improvements to plants will be crucial to integrate a growing share of variable renewable generation into the grid system.

Reducing local air pollution from coal plants continues to be a priority, and the importance of improving CCUS for coal to conform with carbon constraints is increasingly being recognised.

Several innovative approaches are being explored, such as integrated gasification fuel cells, direct coal fuel cells and supercritical CO2 power cycles. These technologies, which promise ultra-high efficiencies, are at different stages of development, with several technical and engineering challenges that still need to be overcome.

Need for higher combustion temperatures and efficiencies for pulverised coal-fired power plants

Advanced ultra-supercritical (AUSC) coal plants promise higher combustion temperatures and efficiencies, and hence lower emissions. Certain technological limits have yet to be overcome, however, to address the high temperatures and pressures. The SDS envisions a shift in the coal power plant fleet towards the highest-efficiency plants (USC and AUSC), and away from subcritical and supercritical technologies.

Innovation needs in renewable power

Renewables require continued innovation efforts to reach the performance, reach and deployment in the SDS. The front-runners in deployment in the SDS, wind and solar, will require continued R&D into next generation modules, cells, turbines and system designs, as well as into balance-of-system components to ensure cost reduction trends are maintained.

More fundamentally, reaching high shares will require bridging innovation gaps in a host of integration technologies. New designs and prototypes are also needed to expand the reach of renewables, including floating off-shore wind turbines, ocean power or enhanced geothermal systems. Biomass technologies will require novel processes to reduce costs and tap into new feed-stocks.

Onshore wind

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