IN-DEPTH: THE CHALLENGE of USING BIOFUELS TO CUT TRANSPORT EMISSIONS

Liquid biofuels still have a significant role to play in meeting the UK’s climate change targets.

Image of biofuel.

The Royal Academy of Engineering analysis, commissioned by the UK Department for Transport (DfT) and now-defunct Department of Energy and Climate Change (DECC), reviews the most significant sustainability issues associated with the use of biofuels.

It argues that some biofuels can help the UK to meet the greenhouse gas emissions savings required under EU and UK rules.

They also offer potential options for cutting emissions in tricky-to-decarbonise transport sectors, such as aviation, shipping and heavy goods vehicles (HGVs), it says.

But the report cautions that the use of biofuels can in some cases result in problems, such as knock-on emissions due to land-use change, degradation of land and increases in food prices.

Sensible policies can minimise these downsides by promoting the use of non-food crops and wastes to produce biofuels and disincentivising feedstocks linked to unsustainable land-use change.

Carbon Brief breaks down the main findings of the report, which provides an overview of the current status of biofuels in the UK.

Over the past decade there has been a rising interest around the world in biofuels as a means to cut transport emissions. More than 60 countries have now launched biofuel programmes and set targets for blending biofuels into their fuel pools.

In the UK, transport accounted for 29 per cent of CO2 emissions in 2015, the second-largest source after electricity generation. Emissions in this sector have barely changed since 1990.

Back in 2008, the UK introduced the Renewable Transport Fuel Obligation (RTFO), its main mechanism for supporting the supply of renewable fuels in transport.

This required 2.5 per cent of total road transport fuel to come from biofuels in 2008/09, with the proportion increasing to 4.75 per cent by 2013. It applies to all firms who supply more than 450,000 litres of road transport fuel per year to the UK market.

This is especially a worry for so-called first-generation biofuels, which are those produced from food or animal-feed crops, such as wheat or soy, rather than from energy crops or waste.

• First generation biofuels are those produced from food and animal crops. They are used to replace fossil fuels and cut emissions. However, there are significant concerns their use could lead indirectly to higher emissions, such as by indirectly increasing deforestation.
• Biofuels are often separated into two other buckets: second and third generation.
• Second generation or “advanced” biofuels are those produced from sources which cannot be used for food. These include dedicated energy crops, such as miscanthus, agricultural and sawmill residues, wood wastes, and used cooking oil.
• The Royal Academy of Engineering  assessment of over 250 separate studies finds these tend to have a greater potential than first-generation biofuels to reduce greenhouse emissions, although this is only the case if there is no land-use change.
• Third-generation biofuels, sometimes also referred to as advanced biofuels, are those produced from algae. According to the report, at their present state of development, these aren’t a viable option: their emissions are currently higher than those from fossil fuels and they are not economic to produce. Algae production is likely to remain restricted to high-value products, such as cosmetics, dietary supplements or speciality chemicals, for some time, the report found.
• The RTFO was expected to be extended to mandate a 10 per cent share for biofuels by 2020, in line with the EU’s 2009 Renewable Energy Directive (RED). This requires a minimum 10 per cent share of renewable energy in member states’ transport sectors by 2020.

However, significant concerns have emerged that the production of biofuels can lead to land-use changes – such as deforestation – which reduce emissions savings, and even in some cases increase emissions above those of the fossil fuels alternative. There are also concerns that the growth of biofuel feedstocks can increase the degradation of land, water resources and ecosystems.

Alongside the disquiet over uncertain emissions savings, there have also been concerns that the use of food crops to produce biofuels could lead to higher agricultural commodity prices. The report notes there is so far little agreement on the magnitude of this problem and its relationship with food security. On the other hand, biofuel markets could also be used as a balance to absorb surplus production of food-crops in normal years and provide a cushion in years of unexpected supply disruptions.

Dwindling interest

For all these reasons, enthusiasm amongst policymakers for increasing the use of biofuels has waned. This was especially the case after a 2008 government-commissioned review by Prof Ed Gallagher, a former Environment Agency chief executive, recommended that targets higher than 5 per cent should only be implemented if emissions from land-use change are avoided. The target in the UK currently remains at 4.75 per cent, far short of the 10 per cent mandated by the EU for 2020.

The Committee on Climate Change (CCC) has also advised caution to ensure biofuels achieve real emissions savings on a lifecycle basis, saying that biofuels’ role in transport should be limited in the long term. However, it has recommended the government should raise biofuels’ share of road-fuel energy to 8 per cent by 2020 and 11 per cent by 2030.

Since the market for biofuels is driven by the legal requirement to blend them into road transport fuel, the current reluctance to increase RTFO as previously expected has caused financial difficulties for UK biofuel plants, the Royal Academy of Engineering report notes.

While the UK maintains an overall commitment to increase biofuels in its energy mix, its use of biofuels has actually slightly decreased since 2013/14, as the graph below shows. Liquid biofuels currently make up about 3 per cent of total transport fuel supplies in the UK (note that the 4.75 per cent biofuel target applies only to road transport fuel).

Supply of biofuels in the UK by fuel type. Source: Royal Academy of Engineering, Sustainability of liquid biofuels, based on 2017 biofuels data from the Department for Transport.

SOURCE: www.eco-business.com