The thing is, there are some hard numbers and some fundamental truths which someone is going to have to find answers for:
- peak oil is happening (or has happened)
- current industrial farming techniques burn up to 10 calories of petro-chemical energy to get 1 calorie of food energy (not an inconsiderate portion of which is fertilizer runoff into waterways and oceans)
- in the past century the bony fish biomass has plummeted to below the weight of shipping tonnage in the world's oceans: https://what-if.xkcd.com/33/
As I've noted before, my grandfather lived in a time when commercial hunting was outlawed --- I worry that my children will live in a time when commercial fishing is no longer viable.
> current industrial farming techniques burn up to 10 calories of petro-chemical energy to get 1 calorie of food energy
The phrase "up to" is doing heavy lifting there.
In particular, this would be production of beef. Production of grains is much more efficient, as is production of poultry, fish, or pork.
It should be noted that in the US, agriculture uses a very small fraction (about 1%) of total primary energy consumption (not counting the sunlight being used by the plants). We use more energy cooking food than we do growing it.
> Large amounts of natural gas are required in the manufacturing of fertilizer and pesticide, so these amounts are categorized as indirect energy consumption on farms.
So seeing as modern industrial agriculture only exists because of the Haber-Bosch process and pesticides, but those are counted as indirect inputs, your phrase "primary energy consumption" is also doing a fair amount of heavy lifting.
And that's not counting all of the supply and cold chains needed to get that food to your supermarket. All these hydroponic/indoor-fresh-greens startups are largely about breaking even on the product-to-market side of things.
Primary energy consumption is the right metric here, since it's a 1:1 accounting of inputs to HB, chemical manufacture, and fuels for vehicles. Not a whole lot of electrical input there.
In any case, the amount is small compared to society as a whole, and today's energy intensive agriculture could be sustained even with entirely renewable inputs, although at a cost. It's a small problem compared to shifting the larger economy off fossil fuels.
Not saying it's not the right metric, I'm saying the "1.9% to agriculture" number isn't including fertilizers, chemicals, or supply chains so the food isn't rotting in your silo. It does include fuel for tractors on the farm though.
"Large amounts of natural gas are required in the manufacturing of fertilizer and pesticide, so these amounts are categorized as indirect energy consumption on farms. Overall, about three-fifths of energy in 2016 used in the agricultural sector was consumed directly on-farm, while two-fifths were consumed indirectly in the form of fertilizer and pesticides."
It's ambiguous, so I regret posting the link. Usually in energy accounting, "indirect" means "accounting puts it into a different category, but we acknowledge that other category wouldn't be making it if the demand for them wasn't here in this category and we differentiate it so we don't double-count it". Scope 1 vs Scope 2 & 3 in carbon-reporting land, if you will.
Combining primary and indirect energy is possible, I suppose, but it's not how it's usually done? So I gave a shit link, emissions reporting is dead for at least the next 4 years, and so none of this matters anyways cause we're just burning our way into prosperity for the foreseeable future.
- peak oil is happening (or has happened)
- current industrial farming techniques burn up to 10 calories of petro-chemical energy to get 1 calorie of food energy (not an inconsiderate portion of which is fertilizer runoff into waterways and oceans)
- in the past century the bony fish biomass has plummeted to below the weight of shipping tonnage in the world's oceans: https://what-if.xkcd.com/33/
As I've noted before, my grandfather lived in a time when commercial hunting was outlawed --- I worry that my children will live in a time when commercial fishing is no longer viable.