Heat pump based water heater - Low & medium temperature solar thermal In fact - CLIMAX
This isn’t exactly a solar water heater, or perhaps it is - you decide.
California is considering the promotion of heat pump water heaters that can effectively double up as “batteries” for solar or wind power.
How does this work? When there’s excess solar or wind power generated, through smart signalling, the heat pump is activated to heat the water, which can be used later when required. Not only does this utilize the green power that under some circumstances might not be utilized, it also ensures that the water heating is done using green power.
Looked at another way, this system acts as a "battery", a thermal battery if you wish. A more economical choice compared to Li-ion or lead acid batteries that need to be otherwise used to store the extra solar or wind power.
A smart idea, in our opinion - https://bit.ly/3mk8HXE