But I have no clue how the numbers actually work out.
If there were, then human-powered farming would have been pointless as a food production method.
I very much doubt it would have survived as long as it has as a technology if it were a net energy loss.
Most of the assessments I have seen generally always show that bio-ethanol is a net loss. Only subsidies keep it afloat.
None of the bio-* will make any sense until we have a lot more renewable electricity on the grid. At that point, producing bio-* will basically become an energy storage solution and a way to soak up excess energy production that you couldn't store any other way.
Frankly, I love my combustion engines for fun and sport, and while I fully support the switch to EV, I have long been wondering how the switch will effect my ability to use them for fun Sunday drives. Eventually they will be banned from the roads and the production and distribution of petroleum will slow right down.
With many motorsport vehicles using Ethanol based fuels for its lower temperature burn and higher power output, I suspect that is the fuel that will stick around as a special use product. Appropriately priced, no doubt.
I sort of assume both, but I'd like to hope for one of them.
" 1 acre produces 122 bushels of corn per year, which makes 122 x 2.6 US gallons of ethanol, which at 84000 BTU per gallon would mean a power per unit area of {0.2 W/m^2}; however, the energy inputs required to process the corn into ethanol amount to 83,000 BTU per gallon; so 99% of the energy produced is used up by the processing, and the net power per unit area is about {0.002 W/m^2}. The only way to get significant net power from the corn-to-ethanol process is to ensure that all co-products are exploited; including the energy in the co-products, the net power per unit area is about 0.05 W/m^2."
However, the fundamental problem with biofuels overall is that fuel requirements are so huge. Indeed, total annual fossil fuel usage -- coal, oil and natural gas -- is an appreciable fraction of total annual biomass production through photosynthesis. Everything, all plants, everywhere. The reasons being that energy requirements are so much greater than food and feed requirements, and that photosynthesis is so inefficient compared to PV.
Human land use is a major factor in the current great extinction. Adding large-scale biofuel production would increase extinction rates. But of course, global climate change is also a major extinction driver.
PV and batteries are clearly the way to go.
It's a bit frustrating to have to leave mid-read to define an acronym.
"X is less bad than Y" doesn't mean that X is not bad. Both can be. In this case, both are.
> then have the US reduce emissions to offset
Yes. One way to do that would be to stop planting huge cultures for "bio"-diesel and then fertilizing them to death.
Hybridization would be more efficient by far.
EVs in general (energy production + transport to plug + battery efficiency losses) are more efficient than the biofuel option (growing/fertilizing/harvesting crops -> turning into fuel-> transport/storage->burning in a vehicle)
But what's being discussed? Which crop or where it's grown? Shuffling deck chairs on the Titanic.
In particular, think about the case where US farmers have a good year and many other places have a bad year.
It seems like efficiency and environmental considerations would have us reduce the amount of land devoted to crops as much as possible, but guaranteeing safety of the food supply would mean increasing capacity. So there's a tradeoff here.
At best its only a problem in specific locations and due to political problems. I don't believe its reasonable to demand that progress in renewable energy adoption should be aborted just because some nation on some random corner of the world is experiencing political problems.
https://ourworldindata.org/hunger-and-undernourishment
Even in sub-Saharan Africa under nourishment has gone from ~35% of the population in 1991 to ~18% today.
It's a problem that is being solved.
The way that this is framed really betrays either a bias or a significant gap in understanding on the part of the author. The big one is their neglect of the costs to society borne from extracting and refining diesel from fossil fuel. Instead they focused solely on the costs of the subsidy.
Look at how they mentioned the Argentine subsidy: "Argentina was doing the U.S. a favor, helping it satisfy its biodiesel demands more cheaply"
They're framing this as a net positive for America, but it betrays their perspective: they don't see disincentivization of biodiesel production by American farmers as a negative thing.
This kinda reads like a corn industry hit-piece on a rival technology.
Besides, having third-world countries be dependent on US exports of (heavily subsidized) surplus food is one of the things that causes famines (shortages in the US come out of exports first), and continues the cycle of economic dependency (domestic producers cannot compete with heavily subsidized US exports). The actual fix here would be to develop foreign food production and then have the US reduce emissions to offset.