Hmm... so someone who owns a good amount of acreage should plant an acre of these trees now, wait for them to mature, and then tap them for personal use. 25 barrels = 1050 gallons, and if that isn't crude and only needs filtering, that's all usable. Wow, that'll take a nice chunk out of your diesel costs for a year, especially since the only cost really comes into the operation of a tree tapping system and the filtration. Trees kind of grow on their own, so little to no upkeep there.
If only I had acreage and a diesel vehicle... I'd be on top of this in a hurry, as I think there is still going to be a need for diesel in 20 years or so. Most likely, we'll just have super efficient diesel vehicles, and if nothing else, it'll probably be able to be sold to trucking companies/regular folk who still have older diesel vehicles... unless of course, some EPA law mandated that all diesel and gas-based vehicles are illegal and everyone owns vehicles with different fuel.
But at the rate of progress right now, in 20 years I bet diesel-based vehicles will be even more common than they are now, with more companies turning to bio-diesel capable vehicles instead of gas-based, since there are some good advancements in bio-diesel (such as algae... not that despicable corn ethanol industry).
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