Regulation: Battery buffered configuration

This can be understood as a regulating device like a very big capacity, which operates over the time:

Conceptually, in this operating mode, the battery should not be sized for storing energy over a medium or long period - the water storage in the tank is far more efficient for this task.

It should be meant for yielding a power complement when the sun's power doesn't reach the pump's power threshold, and also absorb the excess energy when it overcomes the pump's maximum power. This way the battery capacity may be reduced to a few operating hours.

In practice the pump is connected to the battery, and operates at the fixed battery voltage at any time. It could be regulated in the same way as any other consumer in a stand-alone system, i.e. turned OFF according to the battery discharge threshold protection. But this would lead to a very intensive use of the battery, in a domain (low charge state) where the wearing is very important.

It would be far better to turn the pump ON only when the sun already yields a significant power, but just not sufficient for activating the pump. This way the battery may be understood as a "power regulating" device.

Therefore the regulating device should act according to an irradiance level sensor (in conjunction of course with the discharge protection of the battery), with a threshold carefully chosen, in such a way that it starts a little before the pump's threshold.

The detailed simulations should help with determining this threshold in each given situation, in order to optimize both the water yield and the battery wearing conditions.

Please have a look on the Results, which indicate that the Battery Buffered performances approach the ones with power converters.