Sunday, February 10, 2008

Biofuels Bad News

According to two studies published this week in Science, when all relevant factors are accounted for, biofuels produce more greenhouse gas emissions than fossil fuels. From Wired:
Biofuels seemed so promising at first -- what could be cleaner than running our cars and factories on plants? But early prognostications were a bit thin on details. They didn't always account for the energy that would be needed to grow, harvest and refine the fuels. Most importantly, they didn't consider that greenhouse gas-gobbling vegetation would need to be cleared for fuel crops -- or, if these were planted on existing pastures, that new fields would be cleared to make space for displaced food crops.

Put these factors in the equation, and biofuels don't do much good at all.

Let's wrench ourselves away from this course before more tax and private money is spent. Let's let our political leaders know that being green requires a little extra research into outcomes.

If I had to guess the future for fueling the vehicle you buy 15 years from now, I'd guess a plug-in hybrid that get the vast majority of its energy from a grid run on these new, ultra-cool maglev turbines. Of course, thin-film solar panels on your own house will also be part of the equation.

8 comments:

Steve Peterson said...

I'm not sure though that those concerns hold for algae-based solutions. New Scientist has a write-up:

Algae
is the Solution


For one thing, I wonder if the algae model is new enough that it was part of the study.

Bruce Cordell said...

Steve,

I think you're right--the studies' conclusions sited by Wired may not hinge on 2nd generation biofuel technologies--the switch grass option still sounds iffy, but algae in tanks could be very interesting option!

Daniel said...

Apart from not being as "clean" as being thought for years, biofuels have another problem: Competition with food: Whatever we burn in your car, other humans cannot eat anymore. And with a growing global population, burning food will be harder to justify than it is even now.

We will need biomass for nonfood-purposes in the future, but I don't think food will be one of them. It is more likely that biomass will be used as subastitute for oil-based basic materials.

My guess is that the future of fuel is hydrogen, produced by wind- and solarpowered electrolysis and used in fuel cells. That is a way to solve one of the problems of solar and wind energy: Their energy production is not related to the the need for energy. "Storing" it in the form of hydrogen makes it available whenever energy is needed.

Btw: Hydrogen-powered cars can be used as hydrogen generators when not used for transportation: Just connect your car with (for example) solar panels and let the fuel cell run on reverse. Cars producing their own fuel... sounds great, doesn't it? :)

Bruce Cordell said...

Daniel,

I have heard that food price increases of late are already tied to crops being set aside for fuel, so your point is scarily real.

Your points on energy storage and transportation are great. I guess it'll be a race to see if long-languishing H fuel cells will improve more quickly than long-languishing battery technology :-)

John DiFrancesco said...

First of all, I think we need to reduce the population of the planet (by natural attrition, not genocide) by a good 50-90% over the next century. That solves a lot of crop/food/water/land scarcity issues. (But that's a rant for another day...)

I think that large scale investment into and adoption of solar power goes a long way. Imagine plug-in hybrids whose entire hood and roof surfaces were covered in thin-film PV, allowing them to partially recharge off-grid, especially in the sunny/southern states. Or every home roofed in PV. Solar panels on the back of every cell phone, ipod, etc. Combine that with advances in LED technology for cool, low-power lighting, and we can really make a dent in our remote energy generation needs, without needing to take food out of people's mouths.

Or drive up the price of our oh-so-precious high fructose corn syrup. (But that's a rant for another day...)

Bruce Cordell said...

John,

It sounds like we would have very similar rants!

Daniel said...

...maybe the question is stupid, but I'm not too deeply into the solar power topic yet, and since we're talking about it here...

What about PV cells getting dirty?

Especially we Europeans like the idea of creating huge "solar farms" in Northern Africa (I believe in desert areas, mostly)and transporting the electric energy in DC highpower lines through the Mediterranean Sea to, well, Europe.

As much as I like that idea, what I don't get is how they will solve the problem of sand and dust that settles down on the PV cell's surface and reduces their efficiency down to zero?

And about your "race"-comment:
We should not think in terms of competition when it comes to different solutions for the energy problem (or almost any problem). Inefficient ideas like biofuels will be scrapped, but I don't see the neessity for "either this or that" thinking. Combinations bring out synergies that often are vastly superior to single-way solutions. Perhaps it's the same here and "batteries and fuel cells"are better than "batteries vs. fuel cells"

Bruce Cordell said...

Daniel,

Good question about dirty PV cells. On mars, frequent windstorms seem enough to do the trick for the rovers--but atmospheric conditions are different here of course.

And, yep, you're right, I doubt one technology will "win." It'll be a combination that gets the job done. It just seems like we're always "about 10-20 years out" from reliable hydrogen fuel tech, thus I threw in the bit about the battery technology coming on strong. 'Course, that could be wrong, too.