Personally, I'm all for going back to the horse and cart, walking or biking. I do little (none) of the latter, purely because as far as I'm concerned, cars and bikes on the same bit of tar do not mix :).
Up until recently, I had glossed over the possibility of converting the car to LPG . LPG stands for Liquefied Petroleum Gas - a mixture of butane and propane. LPG is produced during crude oil refinement, or is extracted from oil or natural gas seams. It's often referred to as autogas in other countries
A conversion seemed pretty costly and I've never owned vehicles I've kept for long enough to recoup the cost. I also wasn't aware of any environmental benefits of LPG.
The Australian Government recently announced a subsidy for LPG conversions, so I took another look at the option, and was very pleasantly surprised. Not only is LPG around half the price of petrol currently, but it also generates 15% less carbon dioxide and 20% less other harmful gases when combusted. LPG is particularly efficient in comparison to petrol in relation to cold engines - which is the situation when taking shorter journeys or even when you're embarking on a longer journey.
LPG also evaporates quickly if spilled, so there's no risk of earth/water contamination. LPG engines are also quieter, so less noise pollution.
Yes, it's a fossil fuel and yes it's not a *real* green, earth-friendly solution, but if I can cut back on what my vehicle spews into the atmosphere; I guess it's better than taking no action at all. Let's call it a small step among many.
Source: Green Living Tips