Now is the time to embrace fuel alternatives
New regulations are coming, that will address big picture targets such as Net Zero Carbon and also incremental updates that drive change over time. In the UK, for example, measures have been put in place to limit the use of off-road ‘red’ diesel (responsible for high NOx and PM10 emissions) in several sectors, including construction.1
These changes provide an opportunity for businesses to take a closer look at their fuel choices, and consider which options enable them to remain both compliant and cost-efficient. In this article, we explore the cleaner burning alternatives that are capturing their attention, with a focus on liquid biofuels.
Currently, the most widely used fuel alternatives are biofuels such as bioethanol for gasoline engines and biodiesel for diesel engines. These can be used as a component in standard fuels, typically amounting to between 5 and 30% of the total volume (depending on legislative requirements) or can even be used as a sole fuel.
Bioethanol can be used in its alcohol form, which is derived from fermented sugar or starch. It can also be converted into ETBE (Ethyl-Tert-Butyl-Ether), which improves its combustion capability and improves compatibility with pipelines and engines in comparison to ethanol.
Biodiesel, on the other hand, is comprised of fatty acid esters, which are obtained by reacting vegetable or animal fat with an alcohol to achieve properties close to those of diesel. It’s also possible to hydrotreat such oils and fats to obtain Hydrotreated Vegetable Oil (HVO), an alternative fuel solution which fully meets the requirements of the Renewable Transport Fuel Obligation (RTFO) and therefore can be used as 100% drop-in fuel.2
Three generations of innovation
First-generation biofuels are produced from edible feedstocks such as beetroot, corn, wheat and sugar cane for bioethanol, or rapeseed, sunflower, soybean, and palm for biodiesel. The downside of these edible feedstocks is that they are also needed for food supply. This concern has led to the development of second-generation biofuels from non-edible feedstocks, such as lignocellulosic biomass and crop waste residues.
More recently, we have seen the arrival of third-generation biofuels. These can be produced from algae – microorganisms that convert sunlight, water and carbon dioxide into energy via photosynthesis.
One of the great benefits of algae is that it requires low input to derive a production yield of over 30 times more energy per acre than can be achieved with second-generation biofuel crops. Not to mention, food waste is under the spotlight right now. You may have read a blog post or two about transforming used chip fat into hydrotreated vegetable oil (HVO), but so far, the search continues for a reliable, consistent source of ethically sourced raw materials.
Overcoming challenges
Every fuel alternative has its own unique qualities to accommodate. Bioethanol, for example, may contaminate engine oil through bioethanol dilution during engine operations. This degrades the oil’s ability to protect the engine against high friction, wear, corrosion, and sludge, which in turn can lead to engine failure. In addition, adding bioethanol into gasoline alters its properties, resulting in the corrosion of the fuel injector and electric fuel pump, or problems starting up the engine in cold weather conditions.3
Biodiesel, meanwhile, can cause fuel filter blockage and leave internal and external deposits on the injector, also leading to cold start problems. Fortunately, there are now plenty of engine oil and fuel additive solutions available on the market that are designed to mitigate these effects.
Solutions to watch out for
- Multifunctional additive packages containing deposit control additives, designed to protect vehicle fuel pumps, lines and injectors from build-up.
- Engine oil additive packages and high-quality base oils to protect an engine against friction, wear, corrosion and sludge.
- Zeolite beads to support the drying process during hydrogen production.
Growing opportunities
Where do the opportunities for growth of biofuels now lie? When it comes to bioethanol, Brazil retains its position as a global source of sugar cane feedstock, while China and India are two key growth markets that experts will be looking to in the near term.4 Meanwhile, expanding HVO production in Singapore and the United States is expected to account for over half the predicted increase in biodiesel output.5
Other Alternative fuels
Other cleaner burning fuels to watch out for include:
• Liquefied Natural Gas (LNG), which is known for automotive transportation applications and is now gaining traction in industries such as shipping – its 0% sulfur content is fully aligned with the 2020 sulfur cap put in place by the International Maritime Organization (IMO).7
• Hydrogen is also considered a clean fuel, as it emits water but no CO2 upon combustion. As such, it’s useful for combustion engines, as well as in the fuel cells that are used in electric vehicles. The challenge is keeping it accessible, so innovators are both looking at ways to enable storage on board vehicles and considering how to develop a suitable fuelling network.
3. Food Technol Biotechnol. 2018 Sep; 56(3): 289–311 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6233010
5. Ibid.