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  wcoenen
  Once you realize how much more efficient solar panels are (compared to plants) at capturing energy from the sun, the next logical question is: could it make sense to synthesize food with the help of electricity from solar power?There is a company called Solar Foods which is exploring exactly that: they use solar power to produce hydrogen, feed that hydrogen and CO2 to Xanthobacter bacteria, and harvest the produced protein.https://www.sciencedirect.com/science/article/pii/S016777992...
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  csours
  I'd love to see an investigation into fossil fuel accumulation over geological time scales - especially petroleum.From what I've seen, 10,000 barrels per year is a reasonable guestimate.If that is the case, then just the electrical energy harvested from solar panels in the UK could convert air into fuel at a faster rate than the WHOLE earth (on average over geological time scales) (as long as the fuel conversion/production was at least 1% efficient at converting electricity to fuel).https://www.reddit.com/r/askscience/comments/1owp09/if_oil_t...https://www.sciencedirect.com/science/article/pii/S209624951...
• latentframe
  31/1 is kind of wild and its hard to justify corn ethanol on efficiency alone; so it looks like this exists mainly because of the policy and not because it’s actually a good way to produce energy
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  tim-tday
  Corn ethanol fuel has been a known scam for decades.
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  dlcarrier
  Switchgrass isn't all that uncommon in parts of the US that process corn into ethanol, and it is more efficient but less subsidized, so corn beats it out. Sugarcane is even more efficient, but it doesn't grow in most of the US.The real question isn't about using biofuels in place of electric power, it's most important in place of other fuels in applications where electrification isn't possible, like air travel.Air travel is not only the fastest form of travel in common use, it's also one of the most efficient, due to the thin air at cruising altitudes. If jet fuel derived from sugarcane or switchgrass becomes cost effective, airplanes can be solar powered for cheap.
• getnormality
  If the solar panels are movable we can go back to the Middle Ages formula where some of the land is left fallow each year to improve yields!
• jfengel
  Joules per acre seems an odd thing to maximize. Solar and corn don't require the same land. And we're not running out of land.We know that ethanol isn't really energy efficient. We do it partly because we like having way, way too much food capacity (as a matter of security), and partly because we love to fetishize farmers (especially the ones in Iowa, who get a lot of attention every four years during Presidential campaigns).
• surround
  Its more efficient energy-wise, but isn't the issue that energy from solar panels can't power gas cars?
• iso1631
  Technology Connections covered this a few months ago https://www.youtube.com/watch?v=KtQ9nt2ZeGM - from about 22m to 38m
• kQq9oHeAz6wLLS
  How good are solar panels at converting CO2? How good is corn?It'd be wise to look at all the variables.
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  jqpabc123
  The real reason why the USA can't compete in global manufacturing --- poor leadership.Leadership that caters to special interests instead of the overall, long term benefit of citizens and organizations.Nothing illustrates this better than energy policy and the foibles thereof.Ethanol is a particularly bad idea that only came about due to the farm lobby.Solar and renewables are progressing despite policy oppostion.Cheap energy offers a significant competituve advantage --- that USA policy openly and stupidly rejects.
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  epistasis
  > roughly 12 million hectares of US farmland—an area the size of New York State—is currently devoted to corn crops that are farmed not for food, but for fuel.2.6M - 5.7M hectares (10,000-22,000 sq miles), less than half of this ethanol land, would power all electricity in the US:https://elements.visualcapitalist.com/how-much-land-power-us...For other comparisons, there are roughly 0.8M hectares of rooftop in the United States (table ES-1 here, 8.13e9 sq m https://docs.nlr.gov/docs/fy16osti/65298.pdf).Looking at LLNL's flowchart of energy in the US:https://flowcharts.llnl.gov/sites/flowcharts/files/2024-12/e...that solar will produce ~13 quads of energy. That's out of a total of only 32.1 quads total of all energy services delivered. When electrifying from fossil fuels to electricity, we only need to (roughly) meet that 32.1 of services; EVs very efficiently deliver electricity to the purpose of movement, ICE are like 20%-30% at best. Burning fossil fuels for heat is ~99% efficient, but heat pumps give you 300%-400% efficiency because they move heat rather than convert electricity directly to heat.So converting all ethanol land use to solar would power the entire US; that's ignoring all the wind power we generate, all the hydropower we generate, all the next generation geothermal that will probably come online over the next decade. And at the base of it all, storage is super cheap these days!The transition is possible now, it will be cheaper than fossil fuels, and the longer we let fossil fuel misinformation deceive us, the more we will waste on expensive energy.
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  oidar
  Solar is nice and all - it's is cleaner than fossil fuels, but requires a bunch of inputs. Geothermal really needs to be pushed for more; after the initial investment, requires basically no inputs and has no toxic byproducts or disposal problems."The full technical potential of next-generation geothermal systems to generate electricity is second only to solar PV among renewable technologies and sufficient to meet global electricity demand 140-times over."https://www.iea.org/reports/the-future-of-geothermal-energy/...