Biodiesel: A green alternative fuel that's getting greener

For fleets looking to switch to cleaner, greener vehicles, electric and hybrid vehicles are the options that most often spring to mind. But, as Hitachi Capital Vehicles Solutions’ recent Future of Fuel Report reminds us, there are other alternatives to petrol and diesel that can help to bring down greenhouse gas emissions – alternatives that might be more viable in particular cases. One of these is biodiesel.

What is biodiesel?

Biodiesel is a biofuel made from vegetable oils and animal fats, and is usually blended with regular diesel when used to power vehicles. In fact, all diesel drivers use biodiesel whether they know it or not. That’s because the Government’s Renewable Transport Fuel Obligation (RTFO) requires large fuel suppliers to source some of their fuel from renewable sources, and the diesel that comes out of most forecourt pumps is therefore a blend containing up to 7% biodiesel.

Like normal diesel and petrol, biodiesel produces carbon dioxide (CO2) when it is burnt inside an engine. However, the plants used to produce it also absorb CO2, so the net emissions over its life-cycle are much lower. On average, biodiesel produces only around 10 to 15% the greenhouse gas emissions of fossil fuels.

The changing sources of biodiesel

According to the Government’s latest figures, 686 million litres of biodiesel were supplied under the RTFO in the financial year 2016-17. The vast majority (86%) of that was made from used cooking oil, while most of the rest came from waste animal fat (6.8%), general food waste (2.6%) and brown grease (2.1%). Brown grease is extracted from restaurants’ wastewater or from the sewers.

Back in 2010-11, supplies of biodiesel were actually quite a bit higher (899 million litres), but they were less environmentally-friendly than today’s. Around 39% of it came directly from crops – mostly soy from Argentina, but also significant quantities of soy from the United States; oilseed rape from Germany, the UK, France and Ukraine; and palm from Indonesia and Malaysia.

Those purposely-grown sources have largely been eliminated from the UK’s biodiesel, with almost all of it now being produced from waste. This means that, while the amount of biodiesel has decreased, the greenhouse gas savings because of it have gone up.

The obstacles to biodiesel

So why haven’t more fleets switched to fully biodiesel-powered vehicles? According to our survey of 149 fleet professionals for the Future of Fuel Report, just 7% use them. We also found that the main obstacles were infrastructure, vehicle availability and vehicle cost.

The Government is offering grants towards the cost of electric vehicles and working to increase the number of charge points around the country. Perhaps it should introduce similar policies for biodiesel to alleviate fleet managers’ concerns.