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University of Otago researchers estimate that economic benefits of up to $100 million could be gained by using household appliances to shift more electricity demand into off-peak hours.
A paper by the researchers, including Otago Energy Research Centre (OERC) co-director Dr Michael Jack, was presented yesterday, on the final day of the centre’s conference on energy and climate change.
Otago University master’s student Carsten Dortans was the paper’s first author; the other researchers were Otago University Centre for Sustainability director Associate Prof Janet Stephenson, and Otago centre Visiting Fellow Dr Ben Anderson. The researchers said that, in New Zealand, household energy consumption by hot-water heaters, refrigerators and heat pumps accounted for "a large percentage of total energy generation" during peaks.
Because these appliances could store energy in the form of hot water and cold/warm air, they could also be used as a form of "demand response (DR)" to shift electricity demand out of the peak times.
The technical potential of these three appliances was to reduce daily energy consumption by about 5 gigawatt-hours (GWh) a day during winter peaks.
New Zealand’s annual electrical consumption is about 40,000GWh.
This new approach would reduce demand in overall daily energy consumption, and of required generation, by 20%.
Using spot market prices and congestion period demand charges, "we estimate the economic value of this to be about $100 million", including savings, the researchers said.
Dr Jack said that several other conference speakers, including Transpower general manager, operations and innovation, John Clarke, had also highlighted the benefits of achieving a smoother balance between periods of peak demand, off-peak periods and electrical supply generation.
The Otago paper was based on an Otago report titled Estimating the Technical Potential for Residential Demand Response in New Zealand.
Residential demand response can be defined as a wide range of actions which can be taken at the residential customer side of the electricity meter in response to particular conditions within the electricity system, such as peak period network congestion or high prices.
The report was prepared for the Green Grid project, funded by the Ministry of Business, Innovation and Employment.