This does not sound promising. Scaled linearly to the current level of oil production, this would cover more land area than Brazil and India put together.
(Current production is 90 million oil barrels/day [0] or 1.4 trillion gallons/year. If this biofuel yields 70 million gallons/year out of 250,000 acres, that's 280 gallons/year / acre; dividing out that's about 5 billion acres, or 18 million km^2. Brazil and India put together are 12 million km^2 [1]).
Perspective on the 280 gallons/acre figure [2]:
"Estimates of Jatropha seed yield vary widely, due to a lack of research data, the genetic diversity of the crop, the range of environments in which it is grown, and Jatropha's perennial life cycle. Seed yields under cultivation can range from 1,500 to 2,000 kilograms per hectare, corresponding to extractable oil yields of 540 to 680 litres per hectare (58 to 73 US gallons per acre).[17] Time magazine recently cited the potential for as much as 1,600 gallons of diesel fuel per acre per year.[18] The plant may yield more than four times as much fuel per hectare as soybean, and more than ten times that of maize (corn)."
Also: [3]
[0] https://en.wikipedia.org/wiki/Petroleum
[1] https://en.wikipedia.org/wiki/List_of_countries_and_dependen...
All biofuel options have this limitation. Peak production for canola oil is around 100 gallons/acre. Yields for algae are higher, around 5,000 - 10,000 gallons (120-240 bbl) /acre for open-air operations (some greenhouse-based operations claim higher productivity though there's a great deal of skepticism over these), but scaling algae biofuel productions up has been extremely problematic to date. All values on an annual basis.
At present rates of consumption in the US (20 million bbl/day, or 7.3 billion annually), you'd need 30 - 75 million acres devoted to fuel production, if I'm getting my math right. Yield claimed here are for 280 gal/acre, or 6.7 bbl/acre.
The vast majority of oil goes to transportation (where it provides 95%+ of the energy used). In some cases (rail, urban/metro private vehicles, transit, canal traffic) electricity or batteries can be substituted. For others (shipping, and especially air traffic) there are few alternatives to liquid fuels, though ships could move on pelletized biomass and/or wind.
Cutting transportation energy requirements would help, but the expectation of much of the world that it will have access to Western levels of per-capita resource utilization would put a huge burden on biological productivity. I don't see the expectations being fulfilled.
Other alternatives include synthesis of hydrocarbons using electricity. The US Navy is researching such methods, which might be able to synthesize aviation fuel using surplus generating capacity from nuclear-powered aircraft carriers (aviation fuel effectively limits cruise duration as it must be frequently resupplied, cost is another factor), and the ability to obtain both carbon and hydrogen from seawater is a benefit, but the process requires _billions_ of gallons of water to be processed. Again, scale of operations is a significant constraint.
My math disagrees with yours, I'm getting 1.1 billion acres? That's about 1/5th of the figure I got for the globe.
https://www.google.com/search?q=%2820+million+oil+barrels+%2...
Any sort of structure in agriculture is hugely expensive because of scale. You're not talking about putting up a backyard trellis, you're talking about building a structure that would cover tens of millions of acres, hundreds of thousands to millions of square miles. That's tremendous.
Farmers normally consider infrastructure such as irrigation ditches, pipes, and harvesting equipment, which comparably are effectively nil scale, to be significant costs of cultivation.
If you think about it, the fact that most farming takes place on little more than scratched earth, and often not even that, speaks to the low level of infrastructure required.
The big difference is that it's more or less carbon-neutral. The carbon released from burning petrochemicals was underground for tens or hundreds of millions of years, and hence increases atmospheric CO₂ concentrations. Like all biofuels, on the other hand, the carbon released from burning jatropha-derived fuels was sucked from the atmosphere as the plant grew.
The big problem with biofuel is that it takes farmland to grow it on which means said farmland isn't making food crops.
Jatropha is interesting, partly for this reason. It grows happily in semi-desert environments that are not suitable for traditional farmland.
Bacterial based processes (generally e.coli) work in digestor/reactors), algae based fuels simply need access to sunlight (can be grown in tubes attached to the side of buildings). Further some starter crops can use land that is not deemed arable by farming standards.
The differentiation is in the length of the hydrocarbons. Most biofuel oil is equivalent to diesel fuel (heavier grade than gasoline), but that's largely tuneable in refinement.
Just plant some switch-grass and shovel it - as is - into a coal plant. No ethanol or anything else. Take the resulting ash (mostly potassium, i.e. potash), and use it as fertilizer, then and do it again.
Because good transportation fuels are hard to find. If you're on a fixed track (rail, trolly), you can electrify. If you're not going too far and can keep your vehicle weight low, batteries become an option. If you've got a big enough structure, you can consider solid fuels (ships). For overland untracked transport (trucks), you might be able to use steam power (allowing solid fuels) at considerable losses of convenience and increase in mechanical complexity.
For heavier-than air craft you're pretty much SOL.
Transportation isn't just moving people around, but everything: food, raw materials, finished goods, and more.
And liquid fuels are also convenient for powering other equipment, especially for mobile, temporary, or remote locations.
Finding a replacement for liquid fossil-fuel based hydrocarbons is the holy grail.
Coal and oil fundamentally changed human existence in ways that are very, very difficult to convey. They've made possible not only all of modern technology, but even the world of 1850, primitive as we would consider it, would be impossible without fossil fuels. Take them away and you're going back before that time, but with 14x the population. Trust me, that's the sort of thing that keeps me up nights.
Though he's rather much the cornucopian, Daniel Yergin's The Prize, both a book and TV series, really impress how much the world changed with the discovery of petroleum in 1859. I highly recommend it:
The are plenty of electrical plants that burn oil.
throwaway_yyD1 above has a better analysis.
