Minnesota’s Third-Largest Wind Farm is Already Losing Steam: Output Falls 14 percent from 2014 Highs

According the National Renewable Energy Laboratory, wind turbines have operational lifetimes of 20 years, but it appears Xcel Energy’s Nobles wind project, the third-largest wind farm in Minnesota, is losing steam after just eight.

The graph below was produced using data from the U.S. Energy Information Administration plant-level data. It shows the electricity generation of the Nobles wind project, which became operational in 2010, through 2018. You’ll notice that electricity generation peaked in 2014, and that generation was about 14 percent lower in 2018, compared to the 2014 production levels.

It is important to take note of this decline in electricity production because such reductions in output have profound implications on the levelized cost energy (LCOE) of the wind project. For those of you who are not familiar with the term LCOE, it is a figure that represents the per megawatt hour (MWh) cost of building and operating a generating plant over an assumed financial lifetime and the quantity of electricity generated by the plant.

We can use the permit application for the Nobles Wind Project submitted to the Department of Commerce to attain capital costs ($2,500/kw), and operating expenses (30/kw, which is lower than EIA estimates for new wind turbines), EIA data production for the capacity factors, paid over a 20 year lifetime.

The table below shows the cost of electricity increasing as the capacity factor (amount of electricity produced) falls.

As you can see, the LCOE of electricity from the Nobles wind project increases by about 17 percent over just five years as the capacity factor falls.

It will be interesting to see if other wind facilities in Minnesota show similar declines in production. If they do, the loss of generation capability must be part of the conversation about why wind and solar simply aren’t the answer for Minnesota’s energy future.