BIOFUEL EMISSIONS: A complex debate about ‘cleaner’

Does filling up with biofuels – instead of regular fuel – save the environment?

That’s sort of like asking if a bag of mixed nuts is healthier than a bowl of fruit. The mixed nuts have more protein and iron, but fruit has less fat, fewer calories and more vitamin C – and everybody digests differently.
What’s cleaner depends on different factors.

A U.S. Department of Energy emissions model does tell us this: From making the fuel to driving down the highway, biofuels release fewer pollutants across many – but not all – categories.

And future changes in vehicle technology, government regulations and fuel production are likely to trim those emissions even further.

For example, using E85 – a mix of 85 percent ethanol with gasoline – is projected to emit 14 percent fewer greenhouse gases than regular gasoline. Greenhouse gases are a combination of pollutants that have an impact on air quality and climate change.

However, E85 releases a greater percentage of volatile organic compounds, which contribute to the creation of ground-level ozone or smog, and particulate matter, which can be harmful to the heart and lungs.

Making a ruling on biofuels is difficult even for some environmental groups who want to champion the alternative fuels but are uncertain of their overall impact. Josh Dorner, spokesman for the Sierra Club in Washington, D.C., agreed that biofuels emit fewer greenhouse gases than fossil fuels, but said there are drawbacks.

“Biodiesel is worse than regular diesel in terms of particulate matter – one of the pollutants more dangerous to human health. And due to its evaporative properties, ethanol at low concentrations can, in fact, worsen ground-level ozone and other air pollutants,” he said, adding that higher concentrations, such as E85, might offset those pollutants.

Biofuel plants also can dirty the air, especially if they’re powered by burning coal, he said.

“Biofuels can either be a boon to the environment and the fight against global warming, or an environmental disaster, depending on dozens of factors,” he said.

Des Moines Register