Hydrocarbons contain massive quantities of easily liberated energy and large quantities of easily liberated hydrogen.
Which are then easily and economically converted to ammonia to power the largest single form of fertilizer used in the world - nitrogen fertilizer, in the form of ammonium nitrate and equivalents. [https://en.m.wikipedia.org/wiki/Haber_process]
10’s of millions of tons/year are produced right now.
That process alone is responsible for likely at least 50% of the human population increase since it was invented, literally billions of people.
It is much harder to get there with any other form of energy, albeit not impossible.
It's harder, but if one looks at the externalities from fossil fuel consumption, it's actually cheaper to use renewable energy now.
Hydrogen for ammonia production is very cheaply storable (underground, like natural gas is stored) and would provide a large dispatchable demand to ease integration of renewables into the economy, smoothing over long timescale intermittency.
In any case, because the energy used for agriculture is so relatively small, if the economy as a whole can get off fossil fuels, agriculture certainly can as well.
Interesting point about electric being only a small part of overall usage --- I guess direct heating and things such as smelting/refining metals makes up the bulk of energy usage?
Transportation. But be careful to distinguish "work" from "primary energy". The latter is raw energy content of fuels, maybe 80% of which is wasted when powering (say) a car. Moving to BEVs would reduce total energy use because as much as 5 units of primary energy gets replaced by 1 unit of electrical energy.
A similar effect (if not as dramatic) occurs when replacing a fuel-burning furnace with a heat pump. In the US, 2/3rds of industrial heat demand is below 300 C and could be addressed with industrial heat pumps of various kinds (especially if the process has a waste heat stream to recycle by feeding it into the heat pump.)
If we’re being honest, I think we should probably also include raw chemicals that would otherwise be used for things like direct heating. So for example, crude oil used for making asphalt, plastic, etc. or natural gas used for fertilizer.
Since replacing them would consume energy too.
That is a less obvious piece of math, but if we’re talking carbon neutral it would matter doesn’t it?
Another resource is sulfur. This is mostly obtained from desulfurization of fossil fuels, but without fossil fuel consumption that source dries up. Making it directly from sulfates could be done, but that requires more energy.
You're skating perilously close to "if something hasn't happened yet, it can't ever happen". This is not valid reasoning.
If the global economy can't get off fossil fuels, we're incredibly fucked, so I suggest there's nothing to be lost by assuming the problem is solvable.
And you’re skating awfully close to the ‘if something could be theoretically solved, that means it is already solved’. That is also not valid reasoning.
I’m pointing out that the scope and scale of the actual changes that need to happen is so large that it will require a lot of work to solve it, in practice. Without everyone (well, 90% probably) starving to death, anyway.
Should we be starting? Yes. But it will require actual concerted effort and significant tradeoffs. And a lot of time.
We’ve been working very hard to get to this point for a century now.
Now you're confusing "solvable" with "solved". Different concepts!
Of course a lot of work would be needed. The work, however, would be justified and very likely rewarded. There don't appear to be any showstoppers that would prevent it from succeeding.
The ultimate problem is one of collective action, internalizing costs that are now externalized. We've solved problems like this before, globally for example with the ban on CFCs. Here the costs and stakes are even higher.
Fossil fuel use will ultimately drive some countries near the equator to such levels of heating that life will become difficult or impossible. India and Pakistan have nuclear weapons, so they (particularly India, which has hydrogen bombs and a much larger economy) can threaten to kick over the global card table if the problem is not effectively addressed.
The issue is that many players are already defacto bankrupt (from a people starving to death/poverty perspective) even while externalizing the costs of fossil fuels.
Like India, Pakistan, many parts of China, Russia, etc.
So easy to say, hard to do. And it’s hard to say that threatening to nuke everyone is going to apply the right kind of leverage, if say India is already starting to drown. Wouldn’t it be better for everyone else then to take their nukes (or nuke them in advance) and let them drown?
Even if others haven’t gotten that far in their line of thinking, I’m guessing India sure has.
The CFC coalition was nothing compared to what will be required to deal with this situation - and notably, the CFC issue still isn’t really solved. Just mostly under control.
Which are then easily and economically converted to ammonia to power the largest single form of fertilizer used in the world - nitrogen fertilizer, in the form of ammonium nitrate and equivalents. [https://en.m.wikipedia.org/wiki/Haber_process]
10’s of millions of tons/year are produced right now.
That process alone is responsible for likely at least 50% of the human population increase since it was invented, literally billions of people.
It is much harder to get there with any other form of energy, albeit not impossible.