Xcel Energy has received a lot of praise for the extremely vague plan that it released last winter to decarbonize its fleet by 2050. However, as with many plans by utilities the devil is in the details, details that were spelled out in Xcel’s long-term plan for Minnesota released earlier this month.

The utility’s “preferred plan” under its Upper Midwest Integrated Resources Plan would wait four years to start building any new wind, and six years to build any large-scale solar. Along the way it plans to shrink the distributed solar market to only 22 MW per year starting in 2021, and slowly strangle it from there on out.

Since community solar is included in its definition of distributed energy, this would mean shrinking or wiping out entirely the state’s leading community solar program.

pv magazine did not find any rationale for this delay in the IRP. However, the utility does claim that it is “currently engaged in the largest build-out of new wind resources” in its history, and estimates a 1.85 GW wind portfolio. Xcel further estimates that by 2024 wind will represent roughly 35% of the electricity supply for the customers in the region, more than any other source.

In the 2025-2032 timeframe Xcel does plan to build around 4 GW of large-scale solar, however this will mean that such projects will only qualify for a 10% Investment Tax Credit (ITC), not the higher rates if they were to start these projects by the end of 2021.

Energy storage in the mix?

By the end of the IRP period in 2034, Xcel is planning for 60% renewable energy on its system. But while the utility talks a lot in the document about the role that energy storage could potentially play, it does not appear to have any concrete plans to deploy batteries beyond the pilot programs that it has in play.

While the utility states that “we are confident utility-scale battery storage will be a part of our long-term resource mix, we are also evaluating the potential for near-term battery storage around our service territories to fulfill distribution system or other needs”, the chart showing its preferred resource mix has a long line of zeros under battery storage stretching to 2034.

And while the utility also states that it will add 1.7 GW of “firm dispatchable, load-supporting resources”, it is not at all clear what technologies it is referring to.

Xcel has much more concrete plans for its existing nuclear reactors. The company plans to run its existing nuclear fleet at least until the end of their licenses. For the Prairie Island nuclear power plant, Xcel is deferring a decision to pursue license extension past its 2034 date at this time, but is proposing a license extension to run its Monticello nuclear power plant through 2040.

Getting to 100%

Xcel has been clear that in order to get past 80% clean energy in a cost-effective manner, it will need technologies that have not been fully developed at this time. This is supported by studies that show that under high wind and solar scenarios it would take a massive amount of lithium-ion batteries to meet demand during cold spells in the Midwest, particularly if nuclear plants are shut down.

Finally, as we have noted, achieving our 100 percent carbon-free electricity by 2050 goal will require further development of technologies that have not yet been identified and commercialized… In addition to potential new battery chemistries mentioned above, potential emerging clean energy technologies include advanced nuclear reactors, carbon capture and storage applications, hybridized gas hydrogen generators, other types of energy storage technologies beyond batteries, and others. As new technologies achieve commercialization, we will remain technology agnostic as we consider including them in our future resource planning analyses.

In other words, like Xcel’s “firm dispatchable, load-supporting resources”, this could be just about anything.