Renewable Identification Numbers (RINs) could be a fantastic deal for investors – if the 2013 trend continues. RINs, part of a federal mandate that requires fuel producers to either make or buy ethanol or to buy RIN ethanol credits, have shot up to $1.25 a gallon. That's a wee bit higher than the price last December, when it dropped down to one cent a gallon. That means there's been a 2,000 percent price increase in prices since the beginning of the year!

The increase comes from 2007 federal guidelines that require fuel companies to produce 13.8 billion gallons of ethanol produced this year. Trouble is, demand is expected to be much lower than that – around 10.6 billion gallons – and so vehicle fuel blenders, which include oil refiners, have to buy credits to meed the requirement. That pushes up the price of RINs like corn stalks after a rain.

Valero Energy thinks that buying RINs will cost the company about $750 million this year.

The US Environmental Protection Agency's drive for E15 in gasoline is unlikely to move forward soon and help meet those ethanol targets, and there hasn't been enough demand lately for typical gasoline with E10 to fill the gap. Valero Energy, the largest oil refiner in the US, thinks that buying all of the RINs it needs to will cost the company about $750 million this year. Valero said consumers will have to pay more at the pump for gasoline to offset the cost.

Two companies involved with futures trading of RINs – CME Group and The Intercontinental Exchange – must be enjoying the 2,000 percent gain. Outside of these two trading companies, though, the market for RINs is "small and illiquid," according to coverage in 24/7 Wall St. Some members of this market have been RIN fraudsters and there are members of Congress who want to see the 2007 ethanol mandates go away, which makes the overall future of RINs questionable.