Energy as a service isn't fungible either. You can not trade energy at one point in time with energy at an other point in time and expect both to have identical

Energy as a service isn't fungible either. You can not trade energy at one point in time with energy at an other point in time and expect both to have identical value. There are many energy speculators which trade is to determining when prices are low or high, and with good weather predictions its not that difficult to make a accurate guess about the price a few days ahead in time.