Within this article it makes the claim that hemp oil is a viable alternative to crude oil. It doesn't go into any detail. It only states that hemp oil is a "clean fuel" while listing in the title "Hemp could free us from oil", among other things.
To what extent can hemp oil be used as a fuel? What is the energy output compared to fossil fuel (oil or coal)? How much hemp would be needed for comparable transportation norms as used by fossil fuel (i.e. a barrel of crude oil is similar to X amount of hemp)? Probably beyond the scope of this site, but what must be done first before hemp can be available for fuel, assuming the engine was engineered to operate on hemp oil, and is that even possible?
Or are these claims based on replacing oil based plastics with hemp based plastics? This article makes a number of claims about hemp plastics, including "Hemp plastic can completely replace oil based plastic materials that we are using today". How does hemp compare as a plastic? How much would be needed to meet current demands for plastics? Can that much hemp be reasonably farmed without stifling other crops?
We already know that hemp is not better than trees for paper, yet those claims continue to be published on the internet, so I have my doubts about hemp oil replacing fossil fuel oil.