Conservative free-market groups are seeking to suspend or eliminate state renewable energy standards on grounds they are driving up the cost of power for consumers and abridge the interstate commerce clause of the U.S. Constitution. In one development, the Manhattan Institute issued a stinging report claiming that renewable power mandates over the past decade have driven up the price of power for consumers by as much as 37 percent. Institute senior fellow Robert Bryce said Feb. 28 that reaching California\u2019s 33 percent renewables standard by 2020 could cost a total of $3,100 per person. He criticized California and other states with renewable energy standards for failing to analyze their cost at a time when 30 percent of the U.S. population is on various federal food aid programs due to the poor economy. Early next month, free-market advocacy group the American Tradition Institute plans to try to advance its legal case challenging Colorado\u2019s renewables portfolio standard on grounds it interferes with interstate commerce, the institute\u2019s legal director David Schnare told Current Feb. 28. By giving preference to in-state renewable generation, the policy gives Colorado generators an unfair economic advantage, according to Schnare. Next month he plans to file a motion to show the organization has legal standing to bring the case. Schnare said the institute plans to fight the case all the way to the U.S. Court of Appeals for the Tenth Circuit, which covers Oklahoma, Kansas, New Mexico, Colorado, Wyoming, and Utah. The case is pending in the U.S. District Court for the District of Colorado (No. 1:11-cv-00859-WJMKLM). Schnare called the legal action the vanguard of a movement likely to involve future challenges to state renewable energy standards by organizations aligned with his institute, as well as unaligned and unnamed others who aim to bring down California\u2019s RPS. The American Tradition Institute is headed by Tom Tanton, a former advisor to the California Energy Commission during the 1990s. According to the Institute for Southern Studies--which seeks progressive economic change in the South--the institute is tied to the Koch Brothers and gets funding from fossil fuel interests. The Institute for Southern Studies investigated the American Tradition Institute after it became involved in litigation involving a climate change scientist at the University of Virginia. It published an expose on Oct. 31.