The cost of deploying wind and solar energy continued to decline significantly in Minnesota last year, and wind — even without federal tax subsidies — may be the state's cheapest source of new electricity.
Those conclusions were included in a report released Monday by Bloomberg New Energy Finance, which annually surveys the U.S. power generation sector for the Business Council for Sustainable Energy, an industry-led group.
The cost of new wind and solar power facilities in Minnesota fell by 16 percent and 23 percent respectively in 2018 over the previous year, the report found.
"We are clearly seeing that these forms of generation are economically competitive," said Gregg Mast, executive director of Clean Energy Economy Minnesota, an industry-led nonprofit that contributed to the Bloomberg report's Minnesota research.
The "levelized cost" of new, unsubsidized wind energy came in at $38 per megawatt hour (MWh), which takes into account the cost to build a power plant and its total power output, according to the Bloomberg analysis. Bloomberg didn't have a state-by-state breakout of the levelized cost of natural gas. But wind in Minnesota is particularly cheap.
"Minnesota has access to some of the best wind resources in the U.S.," the Bloomberg report said. "As a result … new wind build in the state is likely already at parity with new combined-cycle natural gas plants even without incentives."
With the tax subsidies, wind cost $26 per MWh, making it the cheapest bet for new power in Minnesota. The 30 percent U.S. tax credit on wind-energy production is phasing out over the next few years.
New solar-energy projects in Minnesota are competitive with new gas-fired plants when they are subsidized, coming in at $39 per MWh, the Bloomberg report said. But without the 30 percent investment tax credit for new projects, solar appears more expensive than new gas-fired power in Minnesota.
Twenty-five percent of the electricity generated in Minnesota last year was from renewable sources, primarily wind. Coal, nuclear and natural gas respectively provided 36 percent, 23 percent and 15 percent of Minnesota's electricity in 2018, the report said, citing federal energy data.
Coal's share fell in 2018 after being at 39 percent of generation during each of the previous two years. Renewable energy's share dropped one percentage point in 2018 from an all-time high the previous year, because of an 8 percent drop in hydro power production and a 7 percent decline in biomass generation.
Biomass fell after the closure last year of a plant in Benson, Minn., which burned turkey manure to produce electricity. Xcel Energy bought and closed the plant after convincing state legislators that biomass plants are much more expensive than wind power.
When looking at shares of power generation, the Bloomberg report looks at in-state electricity production only. Minnesota has below average in-state power generation as it imports some electricity, mostly from coal-fired plants in North Dakota.