Whereas the aquaponics system is water-based, the system as a whole is very efficient in the use of water to distribute nutrients. There is a small amount of evaporation from the fish tanks and growbeds, but the majority of water used goes into plant and fish growth, i. e., the only water actually removed from the system is in the form of plant material and fish flesh.

Power Generation

The aquaponics greenhouse will have microturbines placed inside during the winter to generate electricity. A microturbine is an aircraft engine that has been miniaturized and turns an alternator. The turbines are inside because the exhaust from burning the alcohol fuel is composed of carbon dioxide and water vapor — at a temperature of around 1300°F. An 80-kw turbine will generate nearly 900,000 BTUs per hour in its exhaust. The carbon dioxide “fertilizes” the air for the plants, increasing growth potential. The plants in turn release oxygen into the air. Each 301 bay of the greenhouse will require approximately 40 kw of power for lighting during the winter. The lighting is essential even on sunny days due to the low angle of incidence of insolation (incoming solar radiation). The sunlight bounces off the roof of the structure and does not penetrate in enough candlepower to benefit the plants. Without lights, there is a very real danger of nitrogen poisoning in green leafy vegetables grown inside. Heat and carbon dioxide levels will be monitored continuously. Should either exceed acceptable limits, the exhaust from the microturbines will be switched to a recouperator — gathering excess heat — and then outside. The recouperator stores excess heat in the thermal mass of the floor.