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What kind of light were you using?

I currently use 5w LED grow lights for garden vegetable hydroponics. They are very cost effective. At about 12p/kwh, make it easy and say lights on for 10 hours a day, that would be 1 kwh every 20 days per light, so 12p per 20 days per light.

From what I understand from people who need to also provide heat to their crops, what they save in electricity cost with LEDs, they end up spending in heating costs. So in some cases it can be a bit of a wash

At the time I was using metal halide/HP sodium lamps. Not as efficient as LED to be sure (LED gives >1.5 times the output per watt) but at scale, even with LED, the energy input required remains substantial. LED does have advantages, e.g., easier to supply illumination at plant level, but indoor growing is still not a cheap or easy thing to accomplish.

> However based on past experience with growing crops under artificial light, I wonder if the investment makes sense. There are a number of issues that have to be addressed, the most urgent is providing enough light for plants to grow. Sunlight is very expensive to replicate with human-made light sources, the energy requirements are steep even with the most efficient illumination available.

Um... How much is premium pot per ounce? That's what they are going to be growing. Indoors.

Sure, but that's the thing, costs make growing "ordinary" crops impractical. The economics of the cannabis industry are probably going to change as legalization spreads. It's unclear, certainly to me, what that will do re: small growing operations in the future. We'd need to hear from an expert on that subject.

For what it's worth, Iceland, right at the polar circle, is particularly proud of their tomato production.

The answer here seems to be 'free energy', in this case due to volcanoes. You can read interesting articles online which detail the experiences.

I would assume this is not for everyone. I would suspect that the main customers would be people not hooked up to the grid, that generates their own energy. As storage costs are steep, using overhead to grow plants seems like a good way to do it. Also, there are many remote areas where during winter or certain periods it is hard to access. Having your own source of vegetables might be important.

The company that develops and improves technology for in-home growing can also think about providing its solutions to space missions, including colonisation.

I doubt if the mentioned examples are worth $200M, but it might be they have an amazing business/growth plan.

If you're in a remote area, why not use a regular greenhouse?

Not all areas let you do this. I am talking about difficult remote, like mountain ranges, lighthouses, isles of the cost of Scotland etc. Not all remote means woods and fields around.

Greenhouses work all the way to the arctic circle. At which point your not going to be getting much energy from solar power. (One trick is to use reflectors to collect more sunlight then concentrate it onto a smaller area, same result as having solar power at a tiny fraction of the cost.) Other option is to use a lot of insulation then tilt the structure. ex: http://waldenlabs.com/5-northern-greenhouse-examples/

Further, solar power takes the same area as you can use to grow crops anyway.

FWIW Iceland gets about 4 hours of daylight near the winter solstice, not a generous amount to be sure. Still, it reduces the requirement for artificial illumination, and with "free" energy from geothermal sources it may be practical enough to grow under glass with supplemental LED illumination. Obviously most anywhere in the US will get more winter daylight which should make greenhouse culture easier to pursue.

Though I couldn't get the link you gave to cooperate, I have seen examples of cold weather greenhouse installations before, so I know that it can work.

You could get a wind power for example, that requires less quality space than solar.

Wind turnbines don't scale down very well. The intermittent nature is also a poor fit for growing plants without storage.

But, if you have excess power from a large turbine it could work.

PS: Solar has surprisingly high energy density. Try running some numbers for this stuff.