Fluid-cooled LED-based lighting methods and apparatus for controlled environment agriculture

A method for controlling an agricultural environment, the method comprising:

• flowing a fluid coolant in a coolant circuit, wherein the coolant circuit comprises:
• a first loop including at least one LED-based lighting fixture from which the fluid coolant extracts fixture-generated heat as the fluid coolant flows in the first loop of the coolant circuit through the at least one LED-based lighting fixture, and
• at least one hydronics loop, fluidically coupled via at least one controllable valve to the first loop including the at least one LED-based lighting fixture, to facilitate temperature regulation in at least a portion of the agricultural environment;
• irradiating a plurality of plants with photosynthetically active radiation (PAR) output by at least one LED-based lighting fixture;
• and
• sensing at least one condition in the agricultural environment via at least one sensor communicatively coupled to the at least one LED-based lighting fixture.

A lighting fixture, comprising:

• an extruded aluminum housing including a first channel formed therein and at least one enclosed cavity formed therein;
• at least one light source mechanically supported by and thermally coupled to the extruded aluminum housing;
• control circuity, disposed in the at least one enclosed cavity of the extruded aluminum housing, to receive AC power and to control the at least one light source;
• and
• at least a first copper pipe, disposed in and thermally coupled to the first channel formed in the extruded aluminum housing, to carry a fluid coolant,
• wherein:
• during operation of the lighting fixture the fluid coolant flowing through the first copper pipe extracts heat generated by the at least one light source of the lighting fixture;
• and
• the first channel and the first copper pipe are positioned in the extruded aluminum housing between the at least one light source and the control circuitry to reduce thermal effects on the control circuitry due to the heat generated by the at least one light source.