Demand response potential of water heaters to mitigate minimum generation conditions

During periods of low electricity demand, particularly when demand drops below baseload supply levels, a system operator can encounter difficulties in efficiently dispatching its generating units. Referred to as `minimum generation conditions (MGC),´ these states are troublesome because they can lead to increased greenhouse gas emissions, depressed electricity prices, or additional barriers to renewables integration. This work explores the potential of using electric water heaters (EWHs), in a demand response (DR) role, to mitigate the number and severity of these MGCs. A detection method for finding MGCs is first applied to the system in Ontario, Canada. At 2018 renewables target levels, it was found that most MGCs would occur in the early morning of spring and fall. To significantly address this issue next generation EWHs employing DR would need a deadband of 10°C to enable the 800+MW required.