Yesterday, August 27, 2018 around 3:31 PM MST, the Colorado Public Utilities Commission (CPUC) voted 2-1 to provide initial approval of Xcel Energy’s Preferred Colorado Energy Plan Portfolio (CEPP). This plan is among several that were considered as part of the 2016 Electric Resource Plan. Formal written approval of the plan is expected by September 4.

In a 2:1 vote, Commission approves the Preferred CEP, with the additional solar+storage project. — Erin Overturf (@erinoverturf) August 27, 2018

While there are a lot of big (and little) numbers floating in last night’s vote, what is really a huge deal is that coal is directly retiring, and gas is explicitly not being built, whereas solar+wind+energy storage are. The energy transition is happening in Colorado in a big way.

The plan calls for retiring Xcel’s coal-fired Comanche Generating Station ten years early, which represents 660 MW of total capacity for two separate units at the site. The Comanche plant represent approximately one-third of Xcel Energy’s remaining coal fleet. The plan does not call for any new gas plants to be built, as earlier versions of the plan had proposed.

This will mean that by 2026, Colorado will reduce CO2 emissions by 60% below their 2005 levels, and will be powered more than 55% by renewable electricity.

The plan features a total of five solar power plants, three of which include include energy storage. Three of these plants – 525 MW-AC worth of solar and 225 MW/ 900 MWh of energy storage – are located in the Pueblo region. A single 72 MW-AC solar plant is located in Park, the western part of the state. And a 110 MW-AC solar plant plus 50MW / 100 MWh of energy storage is located in Adams.

The total solar to be deployed under this plan would be 707 MW-AC, with 275 WM/1,000 MWh of energy storage. The solar power bids ranged from 2.3-2.7¢/kWh, while solar plus storage ranged from 3.0-3.2¢/kWh. While it makes for an imperfect comparison as solar project costs vary, the solar vs solar+storage delta is 0.5-0.8¢/kWh.

This plans approval comes shortly after a deal between Xcel Energy and steelmaker EVRAZ that includes the building of a 240 MW solar project near the company’s Rocky Mountain Steel mill in Pueblo, Colorado, by far the largest behind the meter project ever seen by pv magazine.

Besides all the numbers being numbingly large in capacity and low in price, is the broader continued pattern of solar, wind and energy storage clearly being built in replacement of fossil fuels. In the case of Colorado, we’re actually seeing that customers will save hundreds of millions of dollars even when we’re closing coal plants a decade early – plants that are simply no longer a good economic investment.

The questions that utilities across the United States, and world, are now asking is not if a transition to renewable energy will happen, but how they are going to make the leap themselves. With the coal and nuclear energy begging for handouts to sustain their dying business models, it is clear where the future lies.