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Most of the world’s grain is not eaten by humans

economist.com

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Re: Most of the world’s grain is not eaten by humans

#181

Post by pg314 »

mattashii wrote: post #180
danielheath wrote: post #177

Earlier quoted context omitted.

Global PV cell production is about 1 million square meters per annum. Global farmland is about 45 million square kilometers, approx 1e10 more. Lets say the solar panels cover 10% of the field. That 10% produces 10x as much, so you've approximately doubled your fields overall productivity. We're currently a factor of 1e9 short of producing enough to do so (and it's not like PV cells are not currently produced at scale…

The actual delta is indeed huge, but there were some mistakes in your calculation that result in an answer that is off by some orders of magnitude. Assuming your initial numbers are correct, the approx 1e10 should be 1e7 (rounding down from 4.5e7), as 1 million sqm equals 1 sqkm (this is different from 1 kilo square meter; see cube square law etc.) You also do not take into account that solar panels have an expected…

The initial number of 1 square kilometer of PV panels produced per year doesn't pass the sniff test. An average home installation is already 10 square meters, and a lot more than 100,000 installations are added in a year.

The global production of solar panels was 180 GW in 2020. Assuming around 200 W per square meter, you get 1 billion square meters of solar panels. So their initial number is off by a factor of 1000.

Re: Most of the world’s grain is not eaten by humans

#182

Post by uwagar »

bsder wrote: post #107
lvl102 wrote: post #102

Seems we need to reduce world population by 1/2 or more. Aren’t we at least contracting in developed countries? Anyway to ask India/China to stop growing so fast?

Easy. Educate women. As soon as that happens, the reproduction rate falls below the replacement rate. The problem is that global society is actually not ready for a population that shrinks instead of grows. Many of our institutions are effectively pyramid schemes that rely on more people entering the bottom and paying for them than pull out money and exit from the top. (Side note: I believe China is actually falling.…

easy. eat less meat.

Re: Most of the world’s grain is not eaten by humans

#183

Post by carderne »

karmakurtisaani wrote: post #4

In 70 something years we went from 60% forest coverage of earth's land mass to 30%. I can't help but wonder how it would be without any animal agriculture.

Please edit your post, this is very wrong. It’s more like 50% to 40%.

https://ourworldindata.org/world-lost-one-third-forests

Re: Most of the world’s grain is not eaten by humans

#184

Post by ralfd »

danielheath wrote: post #177
ncmncm wrote: post #108

Earlier quoted context omitted.

Official US agricultural policy and habitual farming practice have made growing maize together with beans and/or squash, tomatoes, and peppers nearly impossible to do competitively. That could be fixed with policy changes that would be fought by the biggest agribusinesses. Corn is among the most efficient natural converters of sunlight into chemical energy useful to the plant (with some left over for the farmer), but…

Global PV cell production is about 1 million square meters per annum. Global farmland is about 45 million square kilometers, approx 1e10 more. Lets say the solar panels cover 10% of the field. That 10% produces 10x as much, so you've approximately doubled your fields overall productivity. We're currently a factor of 1e9 short of producing enough to do so (and it's not like PV cells are not currently produced at scale…

> Global PV cell production is about 1 million square meters per annum.

I think you are of by a few magnitudes as this is only 1 square kilometer? The largest solar park in India is 56 square kilometers in area (or 10 million solar panels which are at least(?) 2 square meters in size).

https://www.youtube.com/watch?v=VyTY1M66mUc

Re: Most of the world’s grain is not eaten by humans

#187

Post by baisq »

codefreeordie wrote: post #2

Most of the world's grain is eaten by humans' food. We're really really good at efficiently producing grain -- especially field corn (which is not super desirable as human food without significant processing), and we grow lots of animals of all sorts. Naturally, when we can, we feed those animals on field corn -- they don't complain, and it's the cheapest food we can produce for them. In the US we also subsidize corn…

>Most of the world's grain is eaten by humans' food.

Evidently.

It's like when, talking about how there are too many cars, they make a separation between "cars" and "humans", as if cars weren't driven by humans. It's very basic manipulation.

Re: Most of the world’s grain is not eaten by humans

#188

Post by ncmncm »

pg314 wrote: post #181
mattashii wrote: post #180

Earlier quoted context omitted.

The actual delta is indeed huge, but there were some mistakes in your calculation that result in an answer that is off by some orders of magnitude. Assuming your initial numbers are correct, the approx 1e10 should be 1e7 (rounding down from 4.5e7), as 1 million sqm equals 1 sqkm (this is different from 1 kilo square meter; see cube square law etc.) You also do not take into account that solar panels have an expected…

The initial number of 1 square kilometer of PV panels produced per year doesn't pass the sniff test. An average home installation is already 10 square meters, and a lot more than 100,000 installations are added in a year. The global production of solar panels was 180 GW in 2020. Assuming around 200 W per square meter, you get 1 billion square meters of solar panels. So their initial number is off by a factor of 1000.

Home installations are usually at several times 10 square meters, or more. 50 is common, 100 seen.

Re: Most of the world’s grain is not eaten by humans

#189

Post by jchmrt »

lvl102 wrote: post #148
wartijn_ wrote: post #137

Earlier quoted context omitted.

That seems like a strange conclusion to draw from this article. It even says "But in fact, more than enough grain is already grown to meet humanity’s needs." Seems more like the number of people isn't the biggest problem, but the lifestyle of a part of those people is. To me it look like the problem will be solved if North America and Europe drastically reduce their meat consumption.

If we can cut our population by 1/2 or even 1/4 we would dramatically reduce pollution and increase resources per capita.

So someone gives an argument which involves less than 1/4 of the world population merely having to change their consumption patterns by eating less meat, but still you see a better solution in 'cutting our population' by more than that? Wouldn't it be better to first focus on the lowest hanging fruit in which we tackle the problem by focussing on those people using a disproportionate amount of resources, instead of indiscriminately reducing the whole population? Not to mention the fact that there are not really any ways to quickly 'cut our pupulation' to this level short of killing people.

Re: Most of the world’s grain is not eaten by humans

#190

Post by idlehand »

Retric wrote: post #93
jazzyjackson wrote: post #69

Earlier quoted context omitted.

If you're pumping water to grow grass in the desert just for the beef, there are better uses for the water. However, cows have the unique ability to turn grass into protein, so if all an area can grow is grass, cows are a great way to get calories out of it. Properly allowed to graze freely, cows can be a net improvement on a particular ecology as a carbon sink (manure is an improvement to the soil), but shipping the…

You get more protein per X acres eating corn than feeding that same corn to cows and eating the cows. If you prefer meat then chicken is worse than eating corn but still much better than cows. We eat beef because it’s delicious and that’s it’s only advantage at scale.

Corn is not a complete protein, though. So it's not a valid substitute for chicken or beef, which do provide all the necessary amino acids.
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