Hydrogen technologies may in the future bring innovation to the current supply of rural electrification technologies. The advantage of hybrid systems is their ability to avoid fluctuations in the system's energy supply, which is the main disadvantage of stand-alone renewable energy technologies such as wind and PV. A hybrid system will provide a relatively constant delivery of energy even when one of the supply devices of the system is unable to generate power (lack of wind in the case of a windmill or of sunlight in the case of a PV).