Kohler

There is an urgency around the climate crisis today. Governments, businesses, and consumers are working toward making substantial changes before it is too late. For mission-critical power, the most popular solution is the diesel generator. While this is a proven, reliable technology, diesel gen-sets emit carbon dioxide (CO2) and other unwanted gases. For mission-critical power users, there is real pressure to reduce emissions from their generators while still ensuring there is no reliability reduction. This includes regulations to adopt cleaner alternatives, for example, Tier 4 in the US, aside from California.

New technologies such as fuel cells and batteries are not yet ready to provide affordable mission-critical power at the scale required. While suppliers are making substantial improvements to the efficiency of their diesel gen-sets, this will not be enough on its own to reduce emissions.

Thankfully, this does not mean we need to rush to adopt temporary or inadequate technologies. Biofuels such as hydrotreated vegetable oil (HVO) can provide an effective, low-emission alternative to diesel right now.
What is HVO?
HVO is a slot-in renewable alternative to conventional diesel that is available today. It can be used in existing infrastructure, such as mission-critical generators, without any modifications and reduces net lifetime CO2 emissions by up to 90%. It is a high cetane fuel, with a cetane number of 70- 90 compared to conventional biodiesel's 50-65 and fossil diesel's 40-55. High cetane has advantages such as better combustion, better cold start, and reduced emissions levels. Cetane number is often seen as a measure of the quality or performance of diesel fuel: the higher the number, the better the fuel burns within the engine of mission-critical equipment such as generators.

HVO is also very stable, with no bacterial growth, making it easier to handle and store than other fuels. It can be kept for up to ten years without any notable degradation. It is not prone to oxidation or water absorption, and it can perform in harsh conditions down to -29 degrees Fahrenheit. With a minimum flashpoint of 141 degrees Fahrenheit, it is safe to use in hotter climates.

The only performance downside to HVO is a slight reduction in power output due to lower volumetric mass. For mission-critical generator users, this does not result in less power electrical output. Rather the fuel consumption will rise by 3-5% to compensate for the difference in volumetric mass. Generator transient response time with the use of HVO is similar to performance with fossil diesel in operation.

At the moment, HVO is more expensive than fossil diesel. However, increased supply as new production plants come onstream is likely to help reduce the price of the fuel.

A plug-in solution

The production process of HVO means that the final product is similar in grade and quality to traditional diesel, so it can be used as a 'slot-in' for existing infrastructure without modification or any need to buy new engines. It is entirely compatible with the standard mix of petroleum-derived diesel fuels, so it can also be blended with traditional diesel – increasing flexibility for the end-user.

HVO is made from waste products and residues that don't impact agricultural land use, including vegetable oils, animal fats, and used cooking oils. It also plugs into a sustainable supply chain, with the use of waste feedstocks encouraging more local production than first-generation biofuels, which often rely on raw materials being shipped around the world. More local supply and production of HVO – closer to the end-user – means reduced carbon emissions associated with transportation.

The HVO production process is different from that used to create first-generation biodiesel, which was based on feedstocks being reacted with short-chain alcohols such as methanol. The process is sufficiently flexible to convert a wide range of low-quality waste and residue materials to hydrocarbon-based drop-in fuels, making it a flexible diesel substitute for a broad range of diesel engine applications. HVO could also be made from photosynthetic organisms such as algae in the near-to-medium term.

A step on the journey to sustainability

For applications such as mission-critical generators, HVO provides a cleaner and more sustainable alternative to conventional diesel and biofuels. The technical and performance characteristics of HVO mean it is becoming increasingly popular as a renewable fuel solution across a broad base of industries. Consequently, multi-million-dollar investments are being made in the global supply chain, and fuel is becoming more readily available from multiple suppliers in the US, China, and Europe. HVO can be produced in dedicated facilities that manufacture only HVO, or it can be co-processed with fossil oil in refineries.

Traceability is also going to become increasingly important, enabling businesses to measure and document their emissions reductions. Organizations such as International Sustainability and Carbon Certification confirm the authentication of feedstocks on a global scale, providing details of where fuel was made, its exact composition, and the amount of greenhouse gas emitted during its production and transportation. This level of traceability provides end-users with guarantees around environmental and ethical sustainability, ensuring, for example, that the production of the fuel has not resulted in damaging activities such as deforestation or land-intensive feedstocks.

Reduced emissions right now

The pressure to reduce emissions is necessary, but change doesn't need to come at the cost of reliability for mission-critical power. HVO is a genuinely risk-free solution that is already available today – and its widespread adoption is set to accelerate the pace of decarbonization rapidly, supporting organizations embarking on a longer-term journey to zero emissions.

Ultimately, generator manufacturers are making strides to ensure they are supporting customers with more sustainable solutions, enabling mission-critical power to continue supporting the next-generation, while helping the transition to net-zero. HVO is a truly drop-in solution, available now, that will play a big role in this journey.