Purix A/S produce a solar powered chiller. and to get a better understanding of what I am writing about, I suggest that you first visit Purix here: http://purix.eu/experience
When Purix started their activities, I helped them for a couple of years getting all the “electrical stuff” into good shape. More information about the early days here:
A picture or drawing can tell more than a thousand words. Here are the schematics of some of the output stages I designed for the Purix Controller: