The Arkansas Public Service Commission is cautioning consumers that natural gas prices are 40 percent higher than a year ago, meaning heating bills will be higher than last winter. The PSC regulates natural gas utilities, but the price for the natural gas itself is determined on the open market and passed on to consumers. The panel advises that a cold winter could drive prices even higher as weather, availability and economic activity can all affect wholesale prices. The PSC has taken steps to try to keep natural gas prices from spiking during volatile times in the market, but higher costs will still have to be paid by consumers. ------ The commission recommends that customers adopt a method of payment that averages monthly bills, giving consumers a relatively consistent bill each month. The panel says customers can save money by adding insulation, making sure heating systems are tuned up and that filters are changed regularly. Also, sealing leaks along windows and doors keeps costs down, as does keeping fireplace dampers closed when not in use.