Tesla has introduced Heat Pump Optimization for its Powerwall 3 and three-phase Powerwall 3P energy storage systems. The feature allows a compatible heat pump to receive instructions to increase its output, storing surplus or inexpensive electricity as hot water.
The feature is currently available only in Europe. Tesla has not announced plans to bring it to the United States or Canada, where the SG-Ready hardware standard used by the system is not widely established.
According to Tesla’s support information, the Powerwall monitors solar production and electricity prices before sending the heat pump one of two signals: normal operation or boosted operation. During a boost, the heat pump raises the temperature of a domestic hot-water or buffer tank beyond the home’s immediate needs. The stored heat can then be used during more expensive periods, reducing the need for the heat pump to operate at those times.
The conditions for a boost vary by Powerwall operating mode. In Self-Powered mode, the system activates it when surplus solar remains after the home’s other loads are covered. In Savings mode, it can respond either to available solar or to the lowest forecast grid prices within a 24-hour tariff period.
The system relies on SG-Ready, a standard developed by the German Heat Pump Association with manufacturers to provide external control of heat pumps. Tesla uses the standard’s contacts to send normal and boosted recommendations rather than managing the heat pump through a cloud connection.
Using the feature requires a Powerwall 3 or Powerwall 3P running firmware 26.26 or later, an SG-Ready-certified heat pump with an accessible SG-2 contact, and physical wiring installed and commissioned by a Tesla-certified installer. The Tesla app must also be version 4.59.1 or newer.
The signals remain recommendations, meaning the heat pump’s own thermostat settings can override them. Tesla says each signal must remain active for at least 10 minutes to comply with SG-Ready requirements. During a power outage, the system returns to normal operation so the Powerwall can prioritize backup loads. There is also no separate on/off switch for the feature in the Tesla app once the equipment has been connected.
Hot-water tanks can provide a useful form of thermal storage. A 300-liter tank heated by an additional 30 degrees Celsius can hold approximately 10.5 kWh of thermal energy. With a heat pump operating at a coefficient of performance of 3, storing that heat would require about 3.5 kWh of electricity, leaving the Powerwall’s 13.5 kWh capacity available for other household loads.
The feature targets a growing European heat-pump market. The German Heat Pump Association reported that 299,000 heating heat pumps were sold in Germany in 2025, a 55% increase from the previous year. Heat pumps accounted for nearly half of new heating systems sold in the country for the first time.
Tesla is not the first company to combine home batteries with heat-pump control. Sonnen introduced a software update in 2023 that allowed its sonnenBatterie system to operate heat pumps using surplus solar power, initially with NIBE units. SG-Ready control has also been used by German photovoltaic energy-management systems for several years.
Sources: Electrek.