Summary

green handleRenewable fuels are a broad classification of fuels, defined as produced from renewable, non-petroleum sources such as crop waste, animal waste or municipal solid waste and include

  • biofuels (vegetable oil used as fuel, ethanol, methanol from clean energy and carbon dioxide or biomass, biodiesel and renewable diesel),
  • hydrogen fuel (when produced with renewable processes) and
  • fuel synthesized from renewable energy sources, such as wind and solar.

This is in contrast to non-renewable fuels such as natural gas, LPG (propane), petroleum and other fossil fuels and nuclear energy. Renewable fuels have gained in popularity due to their sustainability, low contributions to the carbon cycle, and in some cases, lower amounts of greenhouse gases. The geo-political ramifications of these fuels are also of interest, particularly to industrialized economies that desire oil independence.

When using the word “fuel”, the tendency is to think of a liquid used in automobiles, trucks and planes. Nearly 30% of all energy consumed in the United States is used in transportation. Globally, transportation accounts for 25% of energy demand and nearly 62% of oil consumed. Most of this energy, two-thirds in fact, is burned to operate vehicles with the rest going to maintenance, manufacturing, infrastructure, and raw material harvesting.

Renewable fuels are looked at as a means of replacing energy needs from home heating to vehicle fuel to electricity generation. The basic concept is that if we use as much product as we grow or convert as much waste as we produce, then our net impact on the environment should be negligible if not zero. With the tremendous environmental impact of petroleum recovery, refining, and eventual combustion, the drive for an alternative is clear. The challenge is to find a fuel that can replace the practical qualities made from fossil fuels but does not pollute in the same way. A partial solution is renewable fuel, a cleaner form of energy.

Benefits of Renewable Fuels
Renewable fuels can be an alternative to conventional transportation fuels:

  1. 100% renewable and sustainable
  2. Fully compatible with petroleum diesel and jet engines and can be used neat or blended in any proportion. No requirement for blending with petroleum fuels.
  3. Petroleum and renewable fuels can be intermixed during distribution and storage without concerns relative to quality or specifications.
  4. Can be stored over long periods of time with no deterioration in quality.
  5. Renewable fuel is biodegradable, so if spilled, less harm compared to a fossil fuel spill.
  6. Increased energy security: renewable fuel can be produced domestically from a variety of feedstock (raw materials) while creating jobs.
  7. Fewer emissions: carbon dioxide captured by growing feedstock reduces overall greenhouse gas emissions by balancing carbon dioxide released from spent renewable fuel. Blends of renewable fuel can reduce carbon monoxide and hydrocarbons. In addition, the ultra-low sulfur content of renewable fuel enables the use of advanced emission control devices.
  8. Higher performance: renewable fuel high combustion quality results in similar or better vehicle performance compared to conventional diesel.

Renewable Fuel Market
The Energy Independence and Security Act of 2007 (EISA) established the Renewable Fuel Standard 2 (”RFS2”) program, which increased the volume of renewable fuel required to be blended into transportation fuel from 9 billion gallons in 2008 to 36 billion gallons by 2022. Based on the standard, each refiner and importer determines the minimum volume of renewable fuel that it must ensure is used in its transportation fuel.

rfs2

In the past five years, more than 40 commercial airlines around the world have flown an estimated 600,000 miles powered at least in part by biofuels. At least 19 airlines as well as the US military have conducted flights using blends of biofuels. The airline industry that has announced voluntary goals of achieving no rise in net carbon emissions after 2020 and reducing net carbon emissions to half of the 2005 level by 2050.

The chemistry to convert waste into fuels is now being tested around the world. Much of our energy need could be satisfied by turning our waste into liquid fuels. Countries offering biofuel subsidies are leading the race to develop second generation biofuels.

Renewable Diesel vs Biodiesel
Renewable diesel and biodiesel can be manufactured from the same feedstock sources but should not be confused as they are defined by the process in which they are produced.

Biodiesel is typically made by reacting vegetable oil or animal tallow with alcohol via transesterification, producing long chain fatty acid methyl esters (“FAME”), the pure non-petroleum fuel before blending with petroleum diesel, conforming to ASTM D6751 for use in diesel engines.

Renewable diesel (or green diesel) is produced from vegetable oil, animal tallow, brown trap grease and other fats and oils, alone or blended with petroleum, and refined by a hydrotreating or other conversion process. Renewable diesel must meet the same ASTM D775 standard as conventional diesel, allowing it to be legally used in existing diesel infrastructure and vehicles; can be used as a substitute for or blend in any proportion with petroleum-based diesel without modifying vehicle engines or fueling infrastructure; compatible with existing fuel distribution systems; blended renewable diesel can be distributed through modern infrastructure and transported through existing pipelines to dispense at fueling stations.

Renewable diesel offer advantages over FAME to include reduced waste and by-products, higher energy density and improved cold flow properties, with enhanced storage and stability.