He’s copied the basic design of a solar pool heater but managed to do it using ... a PID temperature controller or even an Arduino to make it even better… but it sounds like it works quite ...

It’s a significant limitation when designing solar heating for a greenhouse, which needs heat the most when the sun isn’t out. Consequently, it’s best to regard solar heating as a supplement ...

Essentially, it allows the water heater to get much hotter during times when solar energy is available, and lets it drop to lower values before running the heater on utility electricity during ...