The Technical Potential for Off-Peak Electricity to Serve as Backup in Wind-electric Thermal Storage Systems

Abstract

Despite its potential as a secure and environmentally benign source of electricity, wind's intermittency is proving to be a challenge for many electricity suppliers. One approach to overcoming this intermittency is to match it with a load that can be made to follow the wind, such as electric thermal storage systems for space heating. In such configurations, wind-generated electricity can be used for space heating and, if sufficient surplus remains, for recharging the thermal storage system. When there is a demand for heat but no wind available, the thermal storage system can discharge, meeting the space heating requirements. In extreme cases, when the thermal storage system is fully discharged and there is no wind, some form of backup energy source is required. This article examines the technical potential of off-peak electricity to ensure that wind-charged thermal storage systems are able to bridge periods of insufficient wind. The simulations show that wind heating with off-peak backup can reduce surplus electricity generated from the wind and greenhouse gas emissions. The benefits as well as the limitations of the approach are discussed.