10 July 2008
The UK took a big step back from Biofuels this week. It seems the science has finally caught up with the rhetoric. Are biofuels all they are cracked up to be?
Maybe, but science tells us not the way we are headed now.
First of all let’s start with the basics.
The idea behind biofuels is a good one. The thought process works this way..
We grow corn which takes carbon out of the air and ground. We turn that corn into ethanol to burn in our gas tank. Yes, this will release Carbon back into the atmosphere, but we are just recycling it. The next crop of corn will suck the carbon right back out again.
Another benefit is that countries that use a LOT of oil are not as dependent on Middle Eastern suppliers. If we make enough perhaps we will not have to drill up the ANWAR and a thousand other places to supply our fix.
When we use gasoline (Petrol for you Aussies and UK folks) we are taking Carbon that was long ago taken out of the carbon cycle, and putting it back into the atmosphere.
This is not good because the more Carbon we put into the air, the warmer our planet gets.
It all looks good on paper but the devil is in the details.
When we calculate how much carbon we are saving with biofuels, we have to consider the energy needed to plant the crop. Fertilize the crop. Harvest it and convert it to ethanol. All that takes fuel! Burning that fuel releases carbon, and other pollutants into the atmosphere.
So what happens when you do the math?
The answer is you save about 10-15% of the carbon that would be released from just using oil like we do now. Congress loved the math so much, that last year they passed new requirements that increase dramatically the amount of ethanol we use over the next 15 years. The farmers love it because the price of corn has tripled in 3 years! How much of this rise is due to demand for biofuels is debatable, but a World Bank report released recently says a large amount of the price rise is due to biofuel demand.
While high food prices are a pain in the pocket book to most Americans, and Europeans, they are a pain in the stomach to many people in the third world. If you cannot afford to heat, you go hungry. This is a science blog, so I will leave the important moral issues for someone else. Let’s just follow the carbon.
THE SHOE DROPS HERE
It turns out that a lot of the corn now being grown around the world is being grown on land that was not cropland a few years ago. Therein lies the problem. When you turn an hectare of Prairie grass into a corn crop you release the carbon in that prairie grass, and some of the carbon in the soil into the atmosphere.
With high food prices around the world, there are millions of hectares of rain forest, grass land, and any other vegetation you can think of being plowed under to grow biofuel crops. Not just corn either, Palm oil is the reason that the topical rain forest in Indonesia is under attack.
When we redo the math, and add in the amount of carbon released by turning land already covered by vegeation into biofuel crops, a much different picture emerges.
It turns out that biofuels grown on converted land actually cause MORE carbon to go into the atmosphere. In some cases many times more Carbon! In some cases it will take hundreds of years to save any carbon from the atmosphere. A rain forest stores a LOT of carbon. Cutting it down to grow corn for biofuels will do much more harm than good.
In other words, if biofuels put more carbon into the atmosphere than oil- Better to use the oil!
The American Meteorology Society brought together some scientific experts on Biofuels recently in Washington. You can see their presentatons here:
(Scroll down until you see the biofuels image)
Right now every gallon of ethanol costs the taxpayer 50 cents in farm subsidies. So keep in mind that it is not as cheap as you might think.
So do we dump the idea?
There is VERY promising research that will likely show us how to make biofuels in a sustainable way that does not increase the carbon in our atmosphere. Unfortunately, they may not prove very popular with the National Corn Growers Association.
The evidence is growing that we do not have a lot of time to figure this out. One of the top climate scientists in the world believes we are already out of time. NASA’s James Hansen believes we might have already passed the tipping point, and we can no longer avoid significant changes to our climate.
The river of science supporting climate change has turned into an avalanche. I work hard to keep up with the peer reviewed science, and I have to tell you the news is not good.
Update Sunday 13-07-08:
CBS London correspondent Mark Phillips has done a very good piece on Bio fuels. He actually puts it much more succinctly than I do!