According to a study from the National Renewable Energy Laboratory (NREL) in the United States a high level of wind and solar use would not increase costs or emissions from power plants that have to start and stop frequently to balance the grid.
The study was based on simulations of power generation along the US west coast.
Some studies have indicated that ramping up and down fossil-fuel plants to accommodate wind and solar ends up creating expense and pollution.
The NREL study, however, concluded that with the offsets in operation and fuel savings from renewable energy, the benefits outweigh the costs.
It was prompted by concerns that intermittent wind and solar energy could cause higher maintenance costs and emissions for coal and natural gas plants that have to fluctuate their loads to make up for drops in renewable energy production.
However, the study’s simulations showed that while the frequent cycling of fossil fuel plants would cause higher maintenance costs, they would be used far less because of high levels of solar and wind generation.
With one-third of the grid along the west coast running on wind or solar energy, fossil fuel costs would drop US$7 billion annually in that region, the study said.
Maintenance costs at fossil fuel power plants would jump as much as US$157 million annually, but those costs would be far less than the savings resulting from higher renewable energy usage, the report said.
At the same time, using solar and wind to make up 33 per cent of the grid on the west coast would cut carbon dioxide emissions at least 29 per cent, while reducing nitrogen oxide and sulfur dioxide emissions by at least 16 per cent and 14 per cent, the report said.
A prior phase of the study found that there would be no technical barriers to integrating as much as 35 per cent solar and wind energy into the grid on the west coast.
“High levels of renewable end up creating lower emissions and fuel costs,” said Debra Lew, an NREL senior engineer who oversaw the study.
The key to the analysis was that it looked at energy transmission and balancing across the entire US west coast, Ms Lew said.
“If you were trying to balance one coal-fired plant with one wind farm, it would be very expensive,” she added.
