Hitachi launches CO2 heat pump water heaters with solar and tariff integration

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Hitachi has introduced a new line of CO2-based heat pump water heaters designed to work in conjunction with solar energy systems and variable electricity tariffs. The products were announced in September 2026, according to a report by PV Magazine. The heaters are engineered to optimize energy consumption by responding to tariff signals, allowing users to heat water when electricity is cheapest or most abundant from solar generation. This approach aims to reduce household energy costs while supporting broader grid flexibility and renewable energy uptake.

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