Renewable Diesel Poses Viable Option

Renewable Diesel Poses Viable Option

By now, most are familiar with biodiesel. It is a cost-effective and more environmentally friendly alternative to conventional petroleum-based diesel fuels when used in the correct applications.

“Biodiesel improves lubricity when compared to Ultra Low Sulfur Diesel (ULSD),” says Kaleb Little, senior communications manager, National Biodiesel Board. It also reduces emissions of hydrocarbons, particulate matter and carbon dioxide.

However, there are limitations when compared to petroleum-based diesel. Biodiesel typically has a higher cloud point, which means it may not perform well in low temperatures unless blended with traditional petroleum-based diesel; it has a tendency to absorb more moisture; and it typically produces slightly less power and fuel economy when used in higher blends.

It is also chemically distinct from petroleum diesel and has a separate ASTM standard. “Biodiesel must meet the ASTM D6751, its own separate ASTM standard that was developed back in 2002,” says Little.

Biodiesel comes blended with petroleum diesel fuel in various ratios, from B5, which is 95% petroleum diesel and 5% biodiesel, all the way up to B100, which is pure biodiesel. Engine manufacturers often publish the maximum content of biodiesel recommended, such as B10 or B20.

“Notably, all of the Big Three auto makers — Ford, General Motors and Fiat Chrysler — have supported high biodiesel blends for nearly a decade,” says Little. “Among U.S. heavy-duty truck segments, which account for more than 87% of actual diesel fuel usage, every major engine manufacturer has a recommendation in their owners’ manuals for B20 or higher, except for Daimler’s Detroit Diesel. Vehicle manufacturers don’t warranty fuel, rather just their own parts and workmanship.”

Perhaps the biggest hurdle for biodiesel is the availability of feedstocks to produce it. It is typically made from oils and fats such as soybean oil or used cooking oil, with soybean oil the most common feedstock. These sources are simply not capable of producing enough quantity to completely replace petroleum-based diesel.

The inherent limitations of biodiesel could soon be addressed by an emerging fuel source known as renewable diesel. “Renewable diesel is a drop-in fuel,” says Joanne Ivancic, Advanced Biofuels USA. “It can replace petroleum diesel completely. Also, it has no sulfur and has other properties that make it better than petroleum-based diesel.”

“Biodiesel and renewable hydrocarbon diesel fuel offer higher cetane numbers than traditional petroleum diesel for better combustion,” notes Little. “They also both dramatically reduce life-cycle carbon emissions

Date: 9/5/2016