One of my clients is considering converting his petrol-fueled fleet of vehicles to liquefied petroleum gas (LPG).
He thinks it will save him ~10% on fuel costs each year once.
Many others are thinking of doin the same so I decided to write a short post on the benefits of LPG vs. petrol vehicles and when people should switch.
LPG vs Petrol Vehicles
LPG, also known as propane or autogas, is a by-product of crude oil extraction and the refining process.
Many people consider LPG as an alternative to petrol because they believe the combustion of propane results in lower CO2 emissions. Unfortunately, the jury is still out on this matter.
In fact, two recent studies found conflicting results in terms of the production of hydrocarbons from the combustion of LPG. The first found a significant increase in CO2 emissions compared to petrol and the other showed a slight increase at a low engine load but a considerable decrease at a high engine load.
Particulates Emission and Octane Rating
What is certain is that LPG burns cleaner than petrol. As a result, the emission of particulates is very low.
Moreover, LPG is non-toxic, non-corrosive and free of tetra-ethyl lead and additives.
It also has a high octane rating (The octane rating is a measure of how likely a gasoline or liquid petroleum fuel is to self ignite. The higher the number, the less likely an engine is to pre-ignite and suffer damage).
In terms of fuel costs, LPG costs a little more than half the price of petrol or diesel, but the fuel economy is about 20-25% lower. Therefore you can get much more bang for your buck (or in other words, more miles per gallon).
According to the AA, overall running costs of an LPG car is approx. a third less than a petrol-only car – but only once you've recovered the cost of the conversion.
The cost of converting an existing petrol car so it can run on petrol or LPG costs between £1,500 and £2,500.
When to Switch to LPG
In order to make this investment worthwhile, you will need to travel around 14,000 miles a year (i.e. if you have a typical delivery van then you are most likely doing about 20,000 miles p.a., LPG is, therefore, a good option to consider if you are trying to reduce your total life operating costs for the van).
From an insurance perspective, the Automobile Association advises that the installer should provide you with a registration receipt to show that the conversion has been done correctly. A copy of this will be required by your insurance company.
If you live in Europe (incl. the UK) you should also note that you can't take an LPG powered car through the Eurotunnel, even if the tank has been emptied or disconnected. There are also restrictions in some underground car parks here and in Europe.
It is important to be aware of any location-based restrictions.
In short, the benefits of LPG vs. petrol fuel cars are significant, but only make economic sense if you are running at high engine loads and doing at least 14,000 miles a year.