Controlled environment agriculture facility and method for its operation

The method of growing plants in a controlled environment agriculture facility in which at least a substantial part of the illumination needed for photosynthesis is provided by lamp means disposed in a spaced array within the facility, comprising the steps of:

• (a) providing a plurality of mobile plant grow racks of a number correlated to the number of lamp means as a multiple thereof;
• (b) placing said plant grow racks closely together in an array so configured with respect to the lamp array that in a first position of the grow rack array first alternate racks are fully illuminated while second alternate racks are not, and in a second position the relative illumination of said racks is reversed;
• and
• (c) periodically reciprocating said grow rack array back and forth between said first and second positions thereof to provide alternating periods for each rack during which the illumination level is above and below the plant compensation point.

A controlled environment agriculture facility comprising:

• (a) a plant growth module within which a controlled atmosphere may be maintained;
• (b) an array of plant grow support racks disposed within said module, said racks being each of rectangular configuration with width and length dimensions and being arrayed in proximity to each other with their length dimensions in parallel relation;
• (c) a plurality of lamps mounted in said enclosure above said racks and divided into groups with the lamps of each group disposed along a line parallel to the length dimension of the racks and with the lamp groups spaced along a line parallel to the width dimension of the racks, the spacing between such lamp groups being approximately equal to an integral multiple of the width dimension of said racks;
• and
• (d) means enabling said plant grow support rack array to be reciprocated between first and second positions within the module, said array when in said first position having a first half of the racks thereof disposed sufficiently directly below a respective one of said lamp groups to be fully illuminated thereby and having the other half thereof disposed between said lamp groups so as not to be fully illuminated thereby, and when in said second position having the relative intensities of illumination of the racks of its said halves reversed, thus enabling even distribution of illumination as between all the plant support racks while affording alternating intervals of relatively high and relatively low illumination for each, and enabling access to individual racks of the array by shifting only a portion of the array between its first and second positions.

The method of controlling humidity of the atmosphere within a controlled environment agriculture facility including a recirculating air system provided with air cooling means therein, comprising the steps of:

• (a) cropping the facility with plants the transpiration of which provides a continuing addition of water vapor into the atmosphere within the facility;
• (b) dividing the return air flow from the facility into first and second portions and passing only the first thereof through said air cooling means for cooling the air and removal of moisture therefrom;
• (c) recombining said first and second air portions for recirculation to the facility;
• and
• (d) variably adjusting the ratio of said first and second air portions to obtain a balance between the amount of water vapor added to the system by plant transpiration and that removed by condensation in the air cooling means, to thus maintain desired humidity in the system without other water addition thereto;

The method of growing plants in a controlled environment agriculture facility in which at least a substantial part of the illumination needed for photosynthesis is provided by lamp means disposed in a spaced array within the facility, comprising the steps of:

• (a) providing a plurality of mobile plant grow racks of a number correlated to the number of lamp means as a multiple thereof;
• (b) placing said plant grow racks closely together in an array so configured with respect to the lamp array that in a first position of the grow rack array first alternate racks are fully illuminated while second alternate racks are not, and in a second position the relative illumination of said racks is reversed;
• (c) periodically shifting each of the grow racks of said array in sequence from said first position to said second position thereof to provide a change in illumination level for each rack with respect to the plant compensation point and to provide access to each rack in turn as it is shifted with respect to those next to it;
• and
• (d) periodically returning the racks of said array from said second position to said first position thereof.