If you are a socially responsible investor, you may want to rethink any commitment you have to ethanol and its use as a fuel supplement, oxygenate, and climate change solution.

The U.S. Energy Information Administration (EIA) reports that U.S production of ethanol (the predominate biofuel in use) is the highest it has been since Jan. 2012.

Source:U.S.Energy Information Administration (EIA)

The UN is rethinking ethanol
However, the UN Intergovernmental Panel on Climate Change (IPCC) reports in two of its own Working Group Reports that ethanol may not be all it's cracked up to be. The IPCC states in its Working Group III – Mitigation of Climate Change report, chapter 8, page 21:

...for some biofuels, indirect emissions—including from land use change—can lead to greater total emissions than when using petroleum products... 

In addition, IPCC states that ethanol has a lower energy density...

However, ethanol has about a 35% lower energy density than gasoline, which reduces vehicle range—particularly at high blend levels...

...making it a less effective fuel.

Reducing human food stocks?
There is also strong debate that production of ethanol from human food stocks reduces the available food for human consumption, resulting in global food stress. Princeton University researcher Tim Searchinger conducted research and found that:

Many models... are predicting that even in the long run, much of the food diverted to biofuels will not be replaced... In the short-term, farmers have less ability to boost food production, so more of the crops diverted to biofuels must come from the food eaten by people. These even greater impacts on hunger are likely to continue if governments continue to demand that biofuel production grow at a rate faster than farmers can fully match.

Forbes magazine also reports that U.S ethanol consumption alone accounts for food losses that could feed hundreds of millions:

In 2014, the U.S. will use almost 5 billion bushels of corn to produce over 13 billion gallons of ethanol fuel. The grain required to fill a 25-gallon gas tank with ethanol can feed one person for a year, so the amount of corn used to make that 13 billion gallons of ethanol will not feed the almost 500 million people it was feeding in 2000. This is the entire population of the Western Hemisphere outside of the United States. 

Alternatives to the alternatives
A variety of alternative energy sources show long-term promise, and alternatives that do not draw from human food stocks should be the preferred alternatives. Recent research indicates that isobutanol may be a good alternative to ethanol. It is less corrosive, absorbs little water, has a higher energy content, can be produced in existing retro-fitted ethanol plants, and can be produced from waste cellulose products rather than human food stocks.

The U.S Department of Energy confirms this research with research of their own led by the Oak Ridge National Laboratory:

Using consolidated bioprocessing, a research team led by James Liao of the University of California at Los Angeles for the first time produced isobutanol directly from cellulose. The team's work... represents across-the-board savings in processing costs and time, plus isobutanol is a higher grade of alcohol than ethanol.

"Unlike ethanol, isobutanol can be blended at any ratio with gasoline and should eliminate the need for dedicated infrastructure in tanks or vehicles," said Liao,... "Plus, it may be possible to use isobutanol directly in current engines without modification." 

All investors, and especially socially responsible investors, may want to check out companies such as Dupont (DD) and BP (BP 0.98%), which are collaborating on their Butamax project. These two large companies have the resources to pursue and market Butamax isobutanol products, and now the legal standing as they won the patent case brought against them by rival Gevo. Butamax reports that they are still using human food stocks in their process but they are pursuing alternative stocks.     

Intrexon (PGEN 1.45%) is taking a different approach. Intrexon is working to use the methane components of natural gas as the stock for microbial conversion to isobutanol. This process will not use human food stocks and will take advantage of abundant natural gas resources. While natural gas is a fossil fuel and environmental purists may argue against its use, it does produce a viable liquid fuel substitute to ethanol for use in existing engines. You can read additional details in this Fool.com article.

Frankly, ethanol presents a dilemma for socially responsible investors. It also presents a dilemma for a number of other reasons. If alternative energies are to be mandated upon the consumer then we should use the best alternatives. Isobutanol looks to be a better solution to ethanol both socially and economically.