Systems and methods for selectively producing steam from solar collectors and heaters

A steam production system, comprising:

• a water source;
• a water inlet coupled to the water source to receive water from the water source;
• a solar collector that includes a collector inlet, a collector outlet, and a plurality of solar concentrators positioned to heat water passing from the collector inlet to the collector outlet;
• a heater that includes a heater outlet, a fuel-fired burner, a burner exhaust, a first heater portion positioned in thermal communication with exhaust gases passing from the burner to the burner exhaust, and a second heater portion positioned in thermal communication with the exhaust gases passing from the burner to the burner exhaust, with the first portion positioned downstream of the second portion;
• a first valve positioned between the water inlet, the first heater portion and the collector inlet;
• a second valve positioned between the first valve, the first heater portion and the collector inlet;
• a third valve positioned between the first heater portion and the second heater portion;
• a fourth valve positioned between the collector outlet and the heater outlet;
• and
• a controller programmed with instructions that, when executed, direct the system to operate in each of:
• a first mode with the first, second and fourth valves open and the third valve closed to direct water through the first and second heater portions and bypass the solar collector;
• a second mode with the first and third valves open and the second and fourth valves closed to direct a first portion of water through the first heater portion, direct a second portion of water through the solar collector, and direct both the first and second portions of water through the second heater portion;
• a third mode with the first, third and fourth valves closed and the second valve open to direct water through the first heater portion, then the solar collector, and then the second heater portion;
• and
• a fourth mode with the first and third valves closed and the second and fourth valves open to direct a flow of water through the first heater portion and then the solar collector, direct a third portion of water exiting the solar collector through the second heater portion, and direct a fourth portion of water exiting the solar collector to bypass the second heater portion.