Xcel Energy is proposing to add new solar and wind energy resources to meet the future electricity needs of Colorado, according to a report filed September 10 with the Colorado Public Utilities Commission (CPUC).
The company’s recommendations include 170 MW of utility-scale Colorado solar power, 450 MW of new Colorado wind power and 317 MW of natural gas generation that would provide operational flexibility the utility relies on to reliably integrate renewable resources into its electric supply mix.
Details of the proposal include:
• The addition of 450 MW of Colorado wind generation is an adjustment from the 550 MW the company initially recommended early this summer after its early wind RFP. This additional wind would bring the installed capacity on the company’s system in Colorado to 2650 MW
• The addition of 170 MW of utility-scale solar generation would use single axis tracking to maximize solar generation during the day. The company currently has about 80 MW of utility-scale solar and 160 MW of customer-sited solar generation
• The proposed 317 MW of “low cost natural gas fired generation” would come from existing Colorado power plants that previously supplied Xcel Energy, but would do so going forward at reduced prices. This ‘flexible generation’ allows the company to start, bring up and turn down generation on-line in relatively short periods of time as wind and solar generation vary throughout the day.
• The company also examined whether to continue operating two older company-owned power plants or to replace them with new generation resources. Xcel Energy recommends:
• The permanent closure of the 109-MW, coal-fired unit 4 at the Arapahoe Generating Station in Denver at the end of 2013; and
• The continued operation of Cherokee Generating Station’s unit 4 in Denver as a natural gas facility after 2017 (the plant fuel source will be switched to natural gas from coal by the end of 2017 as part of the Clean Air-Clean Jobs Act Plan).
Xcel Energy’s proposal today still must be reviewed by an independent evaluator for the CPUC and ultimately considered by the Commission which is scheduled to approve the plan as filed or make amendments to the proposal by Dec. 9, 2013.