The farmer-owned cooperative CHS, Inc. said it will cover “a significant portion of the cost to purchase and install an additional storage tank for the purpose of offering E15” at the 1,400 gas stations operating under its Cenex brand name. Based in St Paul, Minnesota, Cenex said the tank program will help meet consumer demand for mid-range blends of ethanol and gasoline. Almost all ethanol sales are at the traditional 10 percent blend. The government has approved E15 but it has only a toehold in the market because of the cost of installing tanks and pumps. Estimates range as high as $300,000 to add E15 to a fuel station but other sources say costs can be as low as $10,000.