Marshall Baxter
Peak Demand Management
Shaving peak-period electrical use with home battery management and custom heat-pump automation.
The context
I have been working on deploying systems to shave electrical use during peak price periods. One part of the system is new management rules for the home battery that was installed with a solar system. This can power some of the load for hours. However, I am also contending with heat pumps. These would quickly drain the battery. To fully cut electrical use during the peak period there are two limits I need to be aware of. The battery can output up to 5kW at any given time and has a total capacity of about 10kWhr. Exceeding ether number causes use of more expansive electricity. As installed, the heat pumps did not support scheduling and could only be controlled by a basic remote control. Luckily, the control boards included an UART interface. After connecting this interface to a microcontroller with WIFI and working out some firmware, advanced automation is possible.
Overview
I have been working on deploying systems to shave electrical use during peak price periods. One part of the system is new management rules for the home battery that was installed with a solar system. This can power some of the load for hours. However, I am also contending with heat pumps. These would quickly drain the battery. To fully cut electrical use during the peak period there are two limits I need to be aware of. The battery can output up to 5kW at any given time and has a total capacity of about 10kWhr. Exceeding ether number causes use of more expansive electricity. As installed, the heat pumps did not support scheduling and could only be controlled by a basic remote control. Luckily, the control boards included an UART interface. After connecting this interface to a microcontroller with WIFI and working out some firmware, advanced automation is possible.