[patrickk]

Another interesting application: growing vegetables very efficiently (potentially in urban areas).

"Plants mainly need blue and red light for photosynthesis and far-red, a colour not even visible to the human eye but visible to the plant….."

This makes LEDs very interesting for this purpose - the ideal light spectrum can be achieved with LEDs. This will make more and more sense over time as the world urbanises further and LEDs get ever cheaper.

http://www.bigpictureagriculture.com/2011/02/plantlab-nether...

[ZoFreX]

I can think of a large market for lighting suitable for growing vegetables in your home that doesn't produce a lot of waste heat...

[patrickk]

It's already been done (LEDs for growing weed, impossible for cops to spot growhouses using FLIR helicopters and much lower power usage so spikes in energy consumption are far less dramatic).

I think in terms of impact, growing vegetables in a sustainable manner that uses little water will be critical for the long term sustainability of cities where water is scarce, such as Dubai or other cities in desert regions.

[anonbanker]

Some people in that market are already seeing harvests equal to 1gram per watt on LEDs. And the quality is as good as a much hotter high-pressure sodium bulb of higher wattage.