A feed-in tariff system for household photovoltaic power generation systems that was started with the aim of expanding the spread of renewable energy. Since 2019, this purchase period will end in sequence, so there is concern that the economic efficiency of households with solar power generation for home use will deteriorate (2019 issue).
As a response to the 2019 problem, a research group at the University of Tokyo constructed an optimal operating model for heat pump water heaters and household storage batteries, and evaluated this economic efficiency.As a result, it was found that the optimum operation of the water heater, that is, the water heater operation in the daytime on a sunny day, brings an average annual cost advantage of 5,800 yen and an energy saving effect of 8% compared to the conventional nighttime operation. rice field.At this time, it was confirmed that the self-consumption rate of household solar power generation increased from 32% to 45%, and that it had the same effect as when a household storage battery of 2 to 4kWh was introduced.
The optimal operating model proposed in this study is aimed at utilizing the demand response of heat pump water heaters.Using past demand / power generation amount and weather forecast information, the next day's hot water supply demand, other power demand, and household solar power generation are predicted at 23:XNUMX the night before, and an operation plan is created based on that.
If the flexibility of the power system like this model is realized, it is possible to expect a large energy saving effect as well as an increase in the consumption of solar power generation for home use.In the future, it is planned to conduct more realistic studies such as how to operate the heat pump water heater that can be introduced into the actual machine in the actual field.
Paper information:[Energy Conversion and Management] A Comparison of the Effects of Energy Management Using Heat Pump Water Heaters and Batteries in Photovoltaic -installed houses
