While David and Charles Koch have donated more than $67 million to organizations that attack climate science, the efforts of their brother Bill – David's twin, and one of the chief antagonists of Aspen's nascent hydroelectric plant – have largely avoided public scrutiny. Bill is best known for his eccentric pastimes, including the "Old West" town he is lavishly re-creating on his 6,400-acre ranch near Somerset, Colorado. He is less politically involved than his brothers, and less wealthy, though he still ranks among the richest men in the United States: His energy conglomerate Oxbow Carbon, which he founded in 1983, has an annual revenue of $4 billion.
Oxbow mines and markets coal, natural gas, and petroleum products. Bill Koch has spent freely to protest environmental regulations that affect his business, and to elect politicians "who understand how foolhardy alternative energy is." This comes as some surprise because Oxbow Carbon has not always been primarily in the carbon business. In the 1990s, Koch invested mainly in geothermal energy and even had a reputation as a leader in the alternative energy sector. Oxbow was at one time the largest supplier of green energy in all of Southern California.
More recently Oxbow's new methane-capturing plant at its Somerset coal mine near Aspen, built in partnership with Aspen Skico, converts waste methane into electricity, eliminating 96,000 tons of carbon dioxide from the atmosphere annually. Oxbow has installed extensive emission-control systems at other plants, as well. But these efforts hardly make Oxbow an "environmental steward," as its website contends. Koch's most recent campaign, backed with $5 million of his personal wealth, has been waged against a proposed offshore wind farm in Nantucket Sound; the fans would blemish the view from his summer compound in Cape Cod. Koch recently said that he is against the wind farm because "it's going to destroy a beautiful environment."