DENVER—With a strong environmental community, a vibrant fossil-fuel industry, and a thriving clean energy sector, Colorado encapsulates all the contending interests driving the complex politics of energy and climate. That's why there are important clues for the national energy debate in the recent partisan collision here over requirements for utilities to generate more electricity from renewable-energy sources.
Such "renewable-portfolio standards," requiring utilities to generate some of their power from sources like solar and wind, have spread widely since the 1990s. Today, 29 states have adopted such mandatory requirements, with another seven having established voluntary goals.
These requirements, as intended, have jump-started the market for renewable energy. Galen Barbose, a research scientist at the Lawrence Berkeley National Laboratory, says the states with these mandates have accounted for about two-thirds of the total increase in renewable generating capacity that utilities have added nationwide in recent years. That means the states with mandates are annually adding enough renewable production to power about 1.5 million homes.
To meet renewable standards, utilities are relying mostly on wind. And with wind-generated electricity now often competitive in price with coal and natural gas, virtually all the states with mandates are on track to reach them at relatively modest cost. Barbose calculates that meeting the requirements has raised electricity rates by less than 3 percent for consumers.