The internet, and especially the Stagea formum in SAU, is no place for political/economic discussions (arguments) take it outside boys!
LPG is only a short term solution, it doesn't help the fact we're running out of oil. We have about 30yrs left of crude, then another 30 available to us in shale oil, which costs about twice as much to extract. Look towards the future of hydrogen fuel cells and improvements in battery storage systems.
Thinking that, i know my kids probably won't ever drive a petrol fueled car. unless of course i get a delorean and Mr Fusion....etc