Auxilliary photovoltaic energy supply for a solar thermal process heat plant

Large solar thermal installations i.e. for industrial process heat need a considerable amount of auxilliary electrical energy for driving pumps, fans, regulation valves etc. Where no electrial grid is available, photovoltaic energy supply seems to be an attractive solution. However, the high costs of photovoltaic electricity and the high inverter losses if 220/380 V AC - consumers are used, need careful design and power management.