We often wonder about the benefits of indoor hydroponic gardening, given that the sun is free. After all, Illegal hydroponic installations are often discovered by their abnormally high electricity use. Last month Sami introduced usto the Omega Garden system; looking at it a bit more closely I wonder, can it make high tech urban gardening economically feasible and actually more energy efficient than growing outdoors?

But Vancouver based Omega Garden's Carousel system rotates the plants around the bulb. They claim that it yields three to five times the weight of plant per watt of electricity used, compared to conventional flat systems. Their commercial carousel system produces as much as a 1500 square foot greenhouse in only 150 square feet, and their LED system just sips electricity.

They claim a lot of advantages; the light is always even and exactly the same distance from every plant, at a close enough distance to get maximum light efficiency. They even provide case studies: For basil, using Fluorescent light took 3.7 kWh to grow a pound; with LEDs, a tenth that at .0.38 kWh. But growing outside uses none, how do you justify this?

Using green power sources coupled with local consumption of the goods produced, would generate close to zero fossil fuel inputs compared to the present system of production with farm tractors, pesticides, a 1500 mile farm to market transportation statistic per food shelf item, along with packaging, refrigeration, etc., all of which are heavily dependent on fossil fuel inputs.

They also claim that it reduces water consumption by 99% and eliminates runoff.

But the most interesting claim is that the rotation of the plants actually increases the yield significantly:

Geotropism relates to the effect of gravity on plant growth hormones called Auxins. Omega Garden discovered that if plants are continually rotated horizontally top to bottom these Auxins are evenly distributed throughout the plant aiding in plant growth and strength.

The distribution of Auxins due to plant rotation increases plant growth rates by several times that of a stationary plant assuming that all other factors are equal. This phenomenon has been termed "Orbitropism" by Omega Garden Int.

Omega also sells smaller rotating residential scaled units (the Volksgarden) for under two thousand bucks.

I am usually a bit sceptical of all of these electric-powered farming schemes, but as I face another winter of turnip and parsnips as we eat our local diet, the idea that I might get a pound of basil for a nickel's worth of green power is very attractive.

Found at Perfect Cube ; Cliff Kuang mentions it in his Popular Science article Farming in the Sky.