Guru
Joined: 11/02/2018
Location: AustraliaPosts: 2398
| Posted: 11:06pm 10 May 2023 |
There is a medium complexity method that gives a rough approximation of peak power tracking. As the amount of sunlight varies the optimum output voltage and current of the panels remain in roughly the same ratio as they are in full sun.
Eg. if the peak power in full sun is 1000W @ 100v and 10A then if the light intensity drops to 1/4 of the peak the power will be 250W at roughly 50V and 5A. A 10:1 ratio in both cases.
An op-amp can compare V and I with its output controlling a PWM signal to a MOSFET in series with the heater, to maintain that ratio. The tank thermostat would switch the PWM off when up to temp.
Not as good as proper tracking but a lot better than none.