Fossil plant cycling costs outweighed by savings

UNITED STATES: The cost of ramping up and down fossil fuel plants to compensate for the intermittent nature of significantly increased wind and solar energy would be lower than previously thought, a study from the US National Renewable Energy Laboratory has found.

by Patrick Smith 25 September 2013

Fossil plant cycling costs will rise if wind power expands signficantly, but by less than previously thought

The research found that high levels of wind and solar power would reduce fossil fuel costs by approximately $7 billion per year across the western US, while incurring costs of $35 million to $157 million per year for cycling the fossil fuel plants.

Under a scenario where 33% of the region's power is generated through renewable sources, the average fossil-fuelled plant would see an increase in operations and maintenance costs of $0.47 to $1.28 per MWh of generation, the laboratory found.

"Grid operators have always cycled power plants to accommodate fluctuations in electricity demand as well as abrupt outages at conventional power plants, and grid operators use the same tool to accommodate high levels of wind and solar generation," said Debra Lew, NREL project manager for the study.

"Increased cycling to accommodate high levels of wind and solar generation increases operating costs by 2 to 5% for the average fossil-fuelled plant. However, our simulations show that from a system perspective, avoided fuel costs are far greater than the increased cycling costs for fossil-fueled plants."