Bio oil

Depending on the boiler it might possible to burn modified vegetable oil in place of heating oil, but there are both environmental and financial reasons why it’s not really an effective solution. If you currently heat your home with oil and are seeking an alternative then a modern wood-fired boiler or perhaps a heat pump is likely to be better.

One of the key issues is that the amount of liquid biofuel we can produce sustainably in the UK is very small, and can meet only a tiny proportion (less than 5%) of the transport fuel demand – let alone further demand from heating. This applies to both oil from crops like oil seed rape, plus the small amount of waste cooking oil available.

To meet a certain energy demand requires far less land for wood fuel than it would for crops like oil seed rape, as the yield in tonnes of fuel per hectare is much higher for wood. In addition, much less processing is needed to make wood into a useable fuel compared to the processing of oil crops (or indeed the processing of waste cooking oil).

If there is a demand for bio-oils beyond what we can meet in the UK, then much more will be imported. This will push up production overseas from, for example, palm oil – with environmental damage from increased deforestation.

Liquid biofuels (like biodiesel or bioethanol) were generally been used for transport purposes in the UK because there was more financial benefit in doing so (due to taxes, although this is no longer really the case). However, there are not usually financial benefits against lower cost heating fuels.

Bulk vegetable oil or commercial biodiesel will both be much more expensive than heating oil. Making your own biodiesel is an involved process and you’ll still need to get the raw material. This is not straightforward – waste cooking oil is generally now collected by companies that pay for it and do the relevant paperwork to show that they’re dealing with it properly. You’ll also need to invest in some modifications to an oil boiler to make it able to burn a biofuel (for some boilers, especially newer ones, this may not be possible anyway).

Given the cost of biodiesel, investing in a modern boiler able to (or even specifically designed to) burn this fuel will still leave high running costs, possibly up to twice as much as an efficient modern wood-fired boiler or a well-designed heat pump system.