[pc86]

> I challenge you to find a technique...where high-calorie foods are grown indoors.

The GP isn't saying this is happening, though. They're saying that selling rich people overpriced kale and strawberries can fund further research and innovation. Maybe the next step is corn. Maybe it's bankruptcy. But it has cash flow to invest in the research to see which one it is, in part from growing and selling the less impactful stuff now.

[ardy42]

> The GP isn't saying this is happening, though. They're saying that selling rich people overpriced kale and strawberries can fund further research and innovation. Maybe the next step is corn. Maybe it's bankruptcy. But it has cash flow to invest in the research to see which one it is, in part from growing and selling the less impactful stuff now.

Something about vertical farms for staple foods just doesn't pass the smell test. One big aspect of farming is the conversion of solar energy to edible chemical energy. Assuming natural plants and some efficient way of using natural light, stacking farmland vertically just means less energy per acre. And barring some new kind of clean energy like fusion, using artificial light will just introduce conversion inefficiencies and expense, at best.

[bertil]

> Assuming natural plants and some efficient way of using natural light

That’s the surprising result of "closed" greenhouses: standard solar panels convert to electricity that convert to LEDs at the right frequency that offer more yield. Plants only absorb very narrow bands of light. Then you have more gains because the plants don’t have to maintain temperature, fight pests, dig deep roots for water; day/night cycle can be optimised. It is leafy greens for now, but there’s no strong reason that other high-energy crops (like sugar cane, carrots, beetroot) wouldn’t work.

Source: Friends working at the Umeå university grow house.

[quantified]

Right. Would it go too far to say that the conversion of solar to chemical energy is the biggest aspect of farming?

I’d like to see the accounting for how much of the “100% renewable” energy is actual production and how much is an accounting practice that involves offsets somewhere. Maybe it is, plants don’t need lighting at night so you could use solar. But the efficiency of sun -> cell -> transmission -> LED -> plant is much less than sun -> plant, it’s not a winner there. Are they attached to the grid and push more electricity to it than they draw?

Balancing production costs vs the carbon chain of transport is good to look at. Our springtime apples come from Chile, New Zealand, and other far-flung places. How many joules of energy went into getting that kale to your Boston store from California vs from Worcester in January? If the energy to grow to harvest is less than the energy to transport, and people really really need that fresh-picked kale in January, it’s a niche win. I’m doubtful you can make much of a dent in New England’s produce needs using New England’s available renewable energy during wintertime. But gathering evidence is better than listening to my doubt.

Vertical orchards- I don’t see that happening. So my apples will still be imported from across the globe.