ENERGY FROM RENEWABLE LIQUID FUELS

HVO AND BIODIESEL FOR DIESEL POWER GENERATORS

The most common fuels used to power generators are diesel and natural gas, but there are other options. Engines for generator sets are available in a wide range of configurations, capable of burning green fuels.

CAT® diesel generators can run on renewable liquid fuels and have been using biodiesel and HVO for more than a decade.

In any case, Eneria can provide guidance and recommendations for switching to renewable liquid fuels.

Renewable liquid fuels for CAT units – HVO and Biodiesel^®

Renewable liquid fuels, such as Hydrogenated Vegetable Oil (HVO) and biodiesel, which have been available in some markets for more than 20 years, are becoming an increasingly popular choice among customers who want to reduce the environmental impact of their operations, as well as an alternative in an era of reduced resources for traditional fuels i.e. gas.

What are renewable liquid fuels for generators?

Renewable liquid fuels are produced from resources such as vegetable oils, including soybean oil, canola oil and palm oil, as well as used cooking oils and animal fats. While resources may vary around the world, complete fuel specifications are independent of the raw material.

HVO and biodiesel are the two main renewable liquid fuels readily available to end users and acceptable for use in the engines of CAT^® power generators:

It should be noted that hydrogenated vegetable oil (HVO)/renewable diesel (RD) complies with diesel specifications, except for density. HVO has a lower density than diesel fuel.

Biodiesel and HVO come from the same raw materials but differ in the processing and chemistry of the final product. Both fuels can be used on their own or mixed with conventional diesel in varying percentages.

Advantages of using HVO and biodiesel from renewable fuels in generators

HVO and biodiesel have similar advantages over diesel and other fossil fuels:

• reduced carbon intensity during engine operation;
• reduced greenhouse gas (GHG) emissions;
• biodiesel is non-toxic and biodegradable;
• reduced carbon monoxide, particulate matter (PM) and sulfate emissions, as well as hydrocarbon emissions and air toxicity;
• both fuels convert free solar energy and atmospheric carbon dioxide into fuel that displaces fossil fuels;
• water savings;
• biodiesel production reduces the amount of wastewater compared to the production of petroleum-based fuels.

• production of petroleum-based fuels.

Biodiesel and HVO specifications and standards for power generators

Biodiesel is registered with the U.S. EPA and is approved for use at any mixture level in both machinery diesel engines and power equipment. In the United States, the applicable B100 mixing specification is ASTM D6751. The specification for the B20 mixture in the US is ASTM D7467. The European EN 14214 fuel standard ensures that biodiesel is suitable even for state-of-the-art CAT engines. EN 16709 describes B20 and B30 biodiesel mixtures.

HVO fuels must comply with EU 15940 specifications. HVOs also meet ASTM D975 and EN 590 diesel specifications except for density.

Performance of biofuels in generators

Engines in generators powered by renewable liquid fuels have similar performance to those powered by conventional diesel, but experience a slight drop in power and fuel economy. The low-temperature properties of HVO and biodiesel must be suitable for the power generator’s ambient environment.

Some regions or municipalities, especially where renewable fuel mandates exist, may have high availability of biodiesel and HVO. In other areas, access to them may be difficult. Then, there is a need to transport them, which – sometimes due to long distances – may reduce the positive environmental impact of these fuels.

Nevertheless, biodiesel fuels are usually more readily available than HVO. This is due to various factors, including the ease of processing and feasibility of the technology.

Use of biofuels in continuous and emergency operation

There is a difference in the applicability of biodiesel and HVO for continuous and emergency generators:

The price of biodiesel mixture varies depending on geographic area, base material (corn, soybeans, etc.), supplier and government taxes. Although renewable liquid fuels may cost more than diesel, owners of generators with diesel engines can switch to these fuels without replacing their engines with new ones. In addition, for fleets of power equipment, managers can switch to renewable liquid fuels without acquiring new stocks of spare parts.

HVO fuels have similar ageing properties to diesel fuel. The differences in the use of biodiesel and HVO for backup power are due to the nature of the fuels. However, biodiesel has a shorter shelf life due to its composition. Biodiesel can age with storage time and deteriorate in quality with age. The shelf life depends on the level of the mixture. Pollution control measures are critical to the use of any fuel, diesel or renewable. Fuels must be protected from water and dirt.

There are specific guidelines for the use of renewable liquid fuels, and users should be aware of the differences when compared to traditional oils and diesel fuels.

When switching from diesel to biodiesel for the first time, shorter service intervals are recommended, with special attention paid to fuel filters, hoses, pumps and seals. Whenever converting your power unit to biofuel, consult your Eneria representative for guidance and information on the proper transition of your new or existing equipment to biofuel. In such a case, Eneria can discuss any adjustments to the equipment that may be necessary to be implemented in a particular installation.

Written bymail: kamil.gwara@eneria.pl

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