Oil vs LPG Boiler: Pros, Cons & Costs

Natural gas’s availability, inexpensiveness, convenience, and reliability make it the ideal fuel choice for heating homes in many UK households. However, there are still close to four million households that are not connected to the gas grid. And if your home is one of them, you have no choice but to turn to alternative energy sources for your heating and domestic hot water needs.

Two of the most popular natural gas alternatives are oil and liquefied petroleum gas (LPG). Oil is currently the leading substitute for natural gas, with around 1.1 million homes presently relying on oil-fired heating systems. On the other hand, LPG is starting to gain popularity, thanks to the introduction of bulk storage tanks. And around 200,000 UK households are currently using LPG fired heating systems to provide central heating and domestic hot water.

Should I install an oil or LPG boiler?

If you live in an off-grid property and are currently scouring the market for a new boiler, you are probably wondering whether to install an oil or an LPG boiler. But before you can make a decision, you need to be informed on the pros, cons, and costs of each boiler and its fuel type. This guide will compare oil and LPG as heating fuels, giving the advantages, disadvantages and estimated costs of using each.

What are the similarities between oil and LPG?

Both heating oil and LPG are liquid fossil fuels with a high-efficiency rating that is almost as high as that of natural gas. In a home set-up, both oil and LPG can fire regular boilers, system boilers and combi boilers to provide heating and hot water. But since both fuels are highly flammable, they are usually stored in special storage containers that can be installed in your garden or underground.  Your boiler then draws the fuel from the container and burns it to generate energy for heating water in your home’s hot water system.

Another similarity between the two heating fuels is that they are bulky and need to be delivered to your property by a designated supplier as they require special handling. Moreover, you need to keep a keen eye on the fuel storage tanks and refill them in time as they can run out without warning.

What are the differences between oil and LPG?

Although heating oil and LPG share some similarities, they differ in more than one way.  For instance, heating oil is a liquid in its natural form. On the other hand, LPG is a colourless hydrocarbon gas that has been compressed and pressured into a liquid form.

In another stark contrast, heating oil is produced through refining crude oil while LPG is typically collected as a byproduct in the crude oil refinery process. LPG can also be tapped from natural gas streams or artificially made by cracking hydrocarbons.

Oil Boilers

Benefits of using an oil-powered boiler

If you opt to install an oil boiler, here are some benefits you will enjoy from having it.

• Oil boilers have a high-efficiency rating that ranges from 90% to 96%. Such a high rating means that almost all the burnt heating oil is converted to usable energy, and only a tiny portion is lost.
• Oil is a cheaper fuel compared to LPG and costs between 48-55 pence per litre.
• Most modern oil boilers are silent and extremely quiet when in operation. This trait is a great win for people who dislike noises in their homes and neighbourhoods.
• Some oil boilers can be installed externally, which helps you save indoor space, especially if you live in a small property.
• Oil is a reliable fuel that heats well even during the coldest of winters. As such, your oil boiler will continue heating your home without hitches or pauses whenever you need it.
• Oil has a good network of national and local suppliers, meaning you will always access fuel whenever you need it.
• Some oil suppliers have fitted customer oil tanks with remote sensors that notify them when your oil supply falls below 30-40%, depending on the season. The supplier then makes arrangements to refill the tank and bills you later.

Cons of using an oil-powered boiler

• Heating oil has a more pungent smell than LPG. Its unpleasant smell can have some effect on vulnerable people such as pregnant women.
• Oil tanks tend to be bulkier and aesthetically unappealing compared to modern LPG tanks. Since the oil boiler will be visible in your garden or behind your house, it is set to stick out like a sore thumb.
• Despite heating oil being a cost-effective heating solution, the upfront installation cost of the oil boiler is quite steep. For instance, installing the boiler and an oil tank alone will cost you upwards of £6,000 compared to around £3,000 for an LPG system.
• There is a high risk of oil spillage, which will cause a more severe environmental impact than LPG spills. As the tank owner, you will also be held responsible for any oil spills, and you are expected to cover the cleanup costs following the spillage.
• Oil tanks and boilers are expensive to service and maintain.
• Poor weather conditions impact delivery. If you live in a remote area, you won’t receive your scheduled delivery when the weather is bad. This will, in turn, affect your heating regime and might leave you vulnerable to the cold weather.
• Oil boilers are becoming rapidly out-phased due to their high environmental impact. The government has stated that no oil boilers will be installed in new homes after 2025. As such, it is not worth it to invest in a technology that is about to be outdated.

Notable oil boiler manufacturers

If your heart is set on installing an oil boiler, you might as well do it right by acquiring one from a reputable manufacturer. The leading oil boiler manufacturers are Worcester Bosch, Grant, Firebird, Warmflow, and Mistral.

LPG Boilers

Now that you have seen the upsides and downsides of using oil to heat your home, you might want to know how LPG fares compared to it. Here is a summary of the advantages and disadvantages of using an LPG boiler over an oil boiler.

Benefits of using an LPG-powered boiler

• LPG boilers are cheaper than both oil and gas boilers. Their prices start at £350 for basic models and end at £2,500 for the most advanced models.
• LPG is an environment-friendly fuel and has 12% lower emissions compared to oil. It also leaves less ash and soot, making it a cleaner fuel compared to oil. Moreover, it runs no risk of oil spills and the accompanying colossal cleanup costs.
• Stored LPG fuel can be used to fuel cooking appliances such as cookers and stoves.
• You don’t necessarily have to purchase an LPG boiler if you are switching over from a gas-powered one. This is because an experienced engineer can help you convert your gas boiler to an LPG boiler at a fee.
• LPG boilers are quieter compared to oil boilers while in operation.
• The fuel storage tank is smaller and more appealing compared to an oil storage tank. Moreover, you can use cylinder storage, which is more compact and can be fitted inside your home. If you don’t fancy a fuel cylinder inside your home, you can also opt to install an underground storage tank that will be out of sight at all times.
• Since LPG boilers are installed and maintained by Gas Safe registered engineers, it is easier to find technicians who can help service and maintain your LPG boiler.

Cons of an LPG-powered boiler

• LPG is more expensive compared to oil and costs between 39-46 pence per litre.
• LPG has few reputable national and local suppliers, meaning it might be hard to find competitive prices and good customer services.
• Storage cylinders are usually small and tend to run out within a few weeks. As such, you may still be forced to go for a storage tank that is bulky and unappealing.
• Failure to monitor your usage and the remaining fuel supply may mean that you run out of LPG in the middle of winter.
• LPG fuel prices are subject to revisions and can rise by as much as 7p per litre going in the second year of use.

Notable LPG boiler manufactures

If you are considering going for an LPG boiler over an oil boiler, ensure you get one from a leading manufacturer to ensure you don’t run into problems down the road. Some of the top LPG boiler manufacturers include ATAG, Worcester Bosch, Baxi, Ideal, and Vaillant.

Oil vs LPG boiler prices

Both oil and LPG boiler need a tank for storing the fuel supply. When installing either type of boiler, you have to factor in the cost of the boiler itself, as well as that of the fuel storage tank. Generally speaking, an oil boiler is more expensive to install than an LPG boiler.

On average, a new oil boiler will cost you £2,000, while an oil storage tank will range from £1,000 to £2,800. The average cost of installing an oil boiler and a storage tank will vary from £3,000 to £4,800. The cost can even be higher if you are installing a boiler from a premium brand.

A new LPG boiler costs around £1,100, while an outdoor storage tank costs between £250 and £1,000. If you opt for a storage cylinder, be prepared to part with around £65 for a 47kg cylinder.

Fuel Prices

Fuel cost prices for both oil and LPG are measured in pence per kilowatt-hour (kWh). Pence per kilowatt-hour is a measure of how much it will cost to heat your home for an hour using a given fuel type. In general, heating your home using oil is cheaper and will cost you 4.81p/kWh, while LPG will cost you around 7.19p/kWh.