Oil from Algae looks promising - and it can absorb excess CO2

[machI]

I can only wish that President Obama sees fit to fund algae research to bring about results in our lifetimes.

From Petri Dish to Gas Pump

By: Joan Melcher | February 08, 2008 | 05:36 PM (PST) |

In a comic book world, a superhero single-handedly addresses the ills of the world. Now imagine a simple organism simultaneously tackling three of Earth’s nagging problems: air pollution, global warming and depletion of energy supply. The organism with this potential is the lowly alga, sometimes known as pond scum. Since the dawn of time, it has been ready for its “15 minutes.”

Microalgae (to distinguish it from such macroalgae species as seaweed) have many desirable attributes for energy producers. Their oil content, in the form of molecules known as lipids, can be as high as 80 percent in dry weight, although 40 percent is more the average — still easily higher than any other biomass feedstock being considered today. Algae reproduce exponentially and can grow about anywhere. In fact, algae prefer salty and sunny conditions, opening up the possibility of using desert and marginal agricultural land for production of algal feedstock. They can even grow in wastewater, and they thrive on carbon dioxide from gas- and coal-fired power plants.

Solazyme is using a standard industrial fermentation process to produce its algal biodiesel. Wolfson believes the company’s proprietary process, based on proven methods that utilize the current infrastructure to refine and distribute the fuel, is the ticket to commercialization, which he sees as possible within the next two or three years.

Arizona Public Service Company (APS) is taking a different tact. It has partnered with GreenFuel Technologies of Cambridge, Mass., to test the feasibility of recycling carbon dioxide emissions from its Redhawk gas-fired power plant. Using GreenFuel’s trademarked technology, smokestack emissions are trapped and transferred to containers holding algae, which consume carbon dioxide and multiply. Estimates are that for every acre of algae grown on the plant site, 150 tons of carbon dioxide can be absorbed — possibly 80 percent of the total emissions from the plant.

http://beta.miller-mccune.com/article/162?article_page=1

[kristopher]

1. Don't you see a bit of a problem with the claims being made?

It's either/or.

Either you can burn the oil produced for fuel, or you can bury the raw algae and sequester to carbon.

The two benefits are mutually exclusive.

[machI]

3. Not all of the algae is made into oil

Some of the residue can just be plowed into the ground to aid agriculture.

The benefits of algae are there in reduced use of fossil fuels. It also has applications in energy storage. I can see collection of solar energy through algae growth and processing it into a hydrocarbon fuel that can be stored for use later.

[lumberjack_jeff]

6. if it's plowed into the ground for agriculture, the carbon finds its way right back into the air.

[TheWraith]

20. No, the carbon is integrated into the soil. nt

[eomer]

4. Can you recycle the carbon in a closed loop?

1. Burn oil (or a derivative) to produce electricity,
2. capture the carbon using algae,
3. turn the algae into oil,
4. loop back to (1.)?
   
   

[lumberjack_jeff]

5. Why is that better than an open loop?

fuel + o2 = co2

co2 + water + nitrogen + algae = fuel

I guess, in a way it is a closed loop with the atmosphere as one of the links.

It's carbon neutral, but unless you use the energy to bury trees, it's not a 2-for-1 deal.

[eomer]

12. Thanks for your patience, bear with me some more.

If the first step is to grow algae in open ponds then we will pull carbon from the atmosphere. Biodiesel is produced from the algae, the biodiesel is burned to produce electricity, the carbon is recaptured into algae, and more biodiesel is produced.

If this process is 100% efficient at capturing carbon from the burning biodiesel then we will have permanently removed carbon from the atmosphere. It will have been captured from the atmosphere and sequestered inside a loop that is closed from a carbon point of view.

The article compares the use of algae with other biodiesel sources like corn and, if I understand it correctly, says that algae solves a major problem of other sources, which is that if you clear new land (like rainforest for instance) in order to grow corn, then the loss of the carbon capturing capacity of the biomass on that land will take a long time to recoup. I guess the theory is that algae could be grown on land that is not currently arable and therefore eliminates that cost that would take a long time to recoup.

I'm sure there is some technical problem with the approach I described -- I have no background in this subject. Please, feel free to educate me.

[kristopher]

13. Did you read the OP?

Last para:
"Arizona Public Service Company (APS) is taking a different tact. It has partnered with GreenFuel Technologies of Cambridge, Mass., to test the feasibility of recycling carbon dioxide emissions from its Redhawk gas-fired power plant. Using GreenFuel’s trademarked technology, smokestack emissions are trapped and transferred to containers holding algae, which consume carbon dioxide and multiply. Estimates are that for every acre of algae grown on the plant site, 150 tons of carbon dioxide can be absorbed — possibly 80 percent of the total emissions from the plant."

You've described a carbon neutral cycle, which is fine. The tech is being spun as a way to make coal "clean" which isn't fine.

[eomer]

14. Yes, I read it.

The article actually discusses several alternative approaches, not just the one you're objecting to.

But I appreciate your explanations and now understand what would be wrong with the approach APS is looking at, which I had no clue about before. Thanks.

[RUMMYisFROSTED]

2. Poops for coupes?

:think:

[kristopher]

7. From the OP:

"Microalgae (to distinguish it from such macroalgae species as seaweed) have many desirable attributes for energy producers. Their oil content, in the form of molecules known as lipids, can be as high as 80 percent in dry weight, although 40 percent is more the average — still easily higher than any other biomass feedstock being considered today. Algae reproduce exponentially and can grow about anywhere. In fact, algae prefer salty and sunny conditions, opening up the possibility of using desert and marginal agricultural land for production of algal feedstock. They can even grow in wastewater, and they thrive on carbon dioxide from gas- and coal-fired power plants."

Algae is a good way store energy in a very usable form - a liquid with high energy density. It provides a much better return on energy input than other biofuels.

But

As indicated by the quote in bold, a frequent impression readers gain from these articles is: Fossil fuel > CO2 capture in algae > Algae to fuel.

I've seen this mental model here on DU so many times that there is no question it results from a quick, uncritical read of these type articles.

My point was to show that it is inaccurate. Algae is great, and it can do both things, it just can't do them with the same batch of algae. At some point the captured CO2 has to be locked away deep underground (shove it back in the coal mines?) instead of being used for fuel.

[Indenturedebtor]

8. Yes. Though it would definately reduce our total CO2 output

The energy used comes from "new" sunlight. Not the sunlight of millions of years ago. It is a nearly carbon neutral source of energy, and would therefore reduce our overall output.

But you could grow algae in ponds in the desert to make it completely carbon neutral.

Ultimately though we'll need to focus on wind, tidal, and solar to power and heat our homes. That's where most of the carbon comes from if i'm not mistaken.

Oh and we'll need to grow our beef in testubes cause all of those car farts are killing us!

[kristopher]

9. "The energy used comes from "new" sunlight"

Here is a discussion of algael biofuel by Robert Rapier at his R-Squared Energy Blog.
http://robertrapier.wordpress.com/category/algal-biodiesel/

If the subject is of great interest to you he provides a link to the close-out report of the U.S. DOE Aquatic Species Program; it is about halfway down the page.

[GliderGuider]

10. I don't get what's so exciting about this

The proposed techniques do not use atmospheric CO2, they use CO2 derived from fossil fuels. As a result this approach depends on fossil fuels being burned in the first place. The best that can be achieved by growing algae is a second pass through the energy cycle, using the carbon originally derived from the fossil fuel to bind the energy from sunlight. This does not result in carbon sequestration.

Even the "second pass" advantage is limited to the energy carried by the amount of carbon actually incorporated in the biofuel. Relative to the total amount of carbon we release from the oil, natural gas and coal (about 24 million tons of carbon per day), that "second pass" amount is unlikely to make any detectable difference to global warming. All it will enable is a tiny bit more human activity for the same amount of carbon.

We would be much further ahead putting our time and energy into actual carbon sequestration (burying either charcoal or raw trees?) and non-carbon energy carriers like wind-generated electricity.

[kristopher]

11. There is hype and reality

The hype is sequestering carbon and allowing the continued use of fossil fuels; the reality is a 3.2:1 EROI for algae diesel compared to a 1.2:1 for ethanol.

[Nederland]

15. Confused

Are you saying that it would better if the CO2 was coming from the atmosphere, or are you just opposed to biofuels altogether?

[GliderGuider]

16. We need to start reducing atmospheric CO2

Making second-pass biofuels using the exhaust from fossil fuel power plants doesn't accomplish that. If we are going to use biofuels, we should at least make them using atmospheric CO2.

With that proviso, and the proviso that the fuels are not made from potential food sources, I'm not categorically against biofuels. I am against biofuels that violate either of those conditions.

On a more philosophical note, I look on biofuels simply as another energy source. IMO the problems that humanity and much of the biosphere face stem from excessive levels of human activity (I=PAT). In order to alleviate those problems I would like to see overall human activity levels reduced. Since energy is the primary driver of our activities, any effort to increase our energy use will increase our activity. Even an attempt to maintain our energy use will maintain a level of activity that has already put our species into overshoot, much to the detriment of the rest of the biosphere. As a result, I'm fundamentally opposed to any further increase in energy production, whether it's fossil fuels, biofuels, or electricity.

I believe that a universal, cooperative, voluntary reduction in our activity and energy use is improbable, so I see one of two possible outcomes. The first is that we will experience involuntary reductions due to the full or partial collapse of industrial civilization. The second possibility is that we will keep on going until we have totally trashed the biosphere -- at which point we will experience a full or partial collapse of industrial civilization.

I do expect that we will try to avert such outcomes through last-minute changes, but I do not expect us to be fully successful. The more we seek to maintain our activity levels through clever technology or industrial expansion, the less successful we will be.

[Nederland]

17. What's the difference?

Making second-pass biofuels using the exhaust from fossil fuel power plants doesn't accomplish that. If we are going to use biofuels, we should at least make them using atmospheric CO2.

What's the difference between making biofuels from atmospheric CO2 and making biofuels from fossil fuel exhaust that under normal circumstances would be dumped into the atmosphere?

[GliderGuider]

18. The main difference I see

Is that the FF approach couples the algae production to continued FF use, while the atmospheric approach doesn't. In practice I suppose there's no difference, but if we follow the first path it can seem (or be spun) that we're reducing the impact of burning FF when in fact we're not. We're merely making it more efficient (getting more energy out of the same carbon), and thereby increasing the level of activity (and the resulting ecological damage) we can get from every unit of carbon. We need to reduce our consumption of fossil fuels, but making them essential to the production of biofuel gives ammunition to those who don't wish to see human activity curtailed.

[GliderGuider]

19. On further reflection, I will modify my position a bit.

In overall energy terms, biofuels are a sideshow -- a mere bagatelle. As such, their manufacture is incidental to the story of the human race and the rest of planetary life. Any negative consequences they might have are lost in the noise of the big picture of human energy use. The one qualification to that is that biofuels must not be made from food sources, as that could have a significant impact on human life.

My major objection is really about the significance of high-density, high-quality energy sources in general to human activity and the consequent ecological damage of that activity.