[Greenbuilding] Growing food by electeric light - urban sustainability?

[Corwyn]

On 6/11/2012 10:13 AM, Alan Abrams wrote:

> I may be stating the obvious, but the notion was based on this:  that if
> one was going to use artificial light to grow crops, then it would make
> sense from an energy use point of view, to grow crops with the highest
> nutritional value--and highest value per unit of area required--which
> might not be simply the highest caloric value.

Absolutely.  And I admit I chose lettuce because Eliot Coleman had 
already done half the analysis for me.  But we are then left with the 
question of where does nutrition come from.  At least some of it does 
not come directly from photosynthesis.  It would therefore come from 
elements in the soil (or other growing medium).  A few plants do get 
their Nitrogen from the air, but the majority need it to come through 
the roots.  I suspect that even to limited extent that nutrition can be 
achieved through light, it will be at the expense of calories. 
Therefore the stated figure for electricity input is likely to be a 
lower bound.

Thank You Kindly,

Corwyn

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Topher Belknap
Green Fret Consulting
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