Enthusiasm for alternative fuels has dropped considerably over the past few years.

Despite a Renewable Fuels Standard (RFS) mandating its use, ethanol isn't doing too well these days--either in mild blends for the majority of cars and trucks, or as E85 for "flex-fuel" vehicles.

But now there's a little more optimism surrounding biodiesel.

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A bipartisan group of 36 Senators--including presidential hopeful Bernie Sanders--is petitioning for an increase in the volume of biodiesel for an updated version of the Renewable Fuels Standard, reports Biodiesel Magazine (via Autoblog).

The Renewable Fuels Standard was passed by Congress in 2007, and requires specific volumes of alternative fuels to be blended with the national supply of gasoline and diesel.

At the time, it was seen as a way to reduce dependence on foreign oil, as well as provide some environmental and economic benefits.

2013 Audi TDI range

2013 Audi TDI range

However, several factors--including increases in fuel efficiency, and the underperformance of the biofuel industry--have brought the standard under fire.

Volumes of "advanced ethanol" not based on corn have never met the mandated volumes, and the problem worsens each year.

Nonetheless, the Senators believe increased production of biodiesel--rather than ethanol--should be encouraged.

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Under proposed Environmental Protection Agency (EPA) rules--which will be finalized in November--the amount of biodiesel blended with conventional diesel will increase to 1.9 billion gallons in 2017.

The Senators want to boost that volume to 2 billion gallons in 2016, and 2.3 billion in 2017.

2014 Ram 1500 EcoDiesel

2014 Ram 1500 EcoDiesel

They claim the industry has the potential to expand and create more jobs.

Their petition to the EPA also calls for eliminating imported biodiesel from the RFS totals, which they claim will protect current U.S. jobs.

The Senators' proposed figures are still lower than the 2.7 billion-gallon total advocated by the National Biodiesel Board trade group for 2017.


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