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Grad student Phong V.V. Le stands with Professor Praveen Kumar in front of a stand of grass. The pair found a potential downside of switchgrass as a biofuel stock -- decreased soil moisture and increased humidity.  (Source: L. Brian Stauffer/University of Illinois)

A new study created a strain of yeast more efficient at turning red algae to fuel via fermentation. The new strand requires only half the time of its predecessor to produce biofuel.  (Source: Antibiotics for)

Algae/seaweed-based biofuels may be the ideal solution for sea-bordering arid regions, such as the Middle East.  (Source: Google Images)
Water usage is a potential concern for using switchgrass as a cellulosic biofuel feedstock

You can ferment it in bacteria.  You can subject it to outlandish temperatures and pressures.  But however you produce biofuel, one thing is constant -- you need a supply of carbon, the "feedstock".

I. Switchgrass == Environmental Threat?

One leading candidate for widespread use as a biofuel feedstock is switchgrass.  Fast-growing and hardy, switchgrass quickly produces a great deal of biomass.  But a new study by the
University of Illinois reveals a potential downside -- switchgrass' growth comes at the cost of soil moisture.

Switchgrass is apparently so effective at sucking water out of the ground that it could cause adverse affects to other human crops, as well as local ecosystems.  
Praveen Kumar, the Lovell Professor of civil and environmental engineering at the University of Illinois states, "While we are looking for solutions for energy through bioenergy crops, dependence on water gets ignored, and water can be a significant limiting factor.  There are many countries around the world that are looking into biofuel energy, but if they are adopting these (large grasses) into their regular policy, then they need to take into account the considerations for the associated demand for water."

The study examined transpiration -- the loss of water through plant pores.  Ultimately
switchgrass and another fast growing grass, Miscanthus, transpire at a higher rate than corn (the most widely used ethanol biofuel crop) and thus pull water from the soil at a faster rate.  This dries the soil and increases humidity.

The researchers also used a predictive model to study what would happen if the predictions of global warming
 were realized.  What they found was that while higher carbon dioxide levels decreased the transpiration rate by allowing the plant to open its pores to the air less frequently, higher temperatures negated this affect by increasing the rate of water loss while the pores were open.  Overall, the predicted affect was even higher rates of water loss.

Regardless of whether the warming scenario occurs, however, the study raises concerns for the viability of switchgrass and Miscanthus as biofuel feedstocks, particularly in drought-prone regions.

The study was published
 [abstract] in the peer-reviewed journal PNAS (Proceedings of the National Academy of Sciences).

Of course, the pro-corn, anti-grass bent should be taken with a grain of salt.  The University of Illinois has a long-standing relationship
 with the corn ethanol community, which would be displaced in a move to switchgrass cellulosic ethanol.  While this particular study was funded by a National Science Foundation grant, given the overall financial situation, it's possible that researchers at the University of Illinois could feel incentivized to find downsides of switchgrass and the upsides of corn.

II. Algae Could be the Cream of the Crop

That said, the University of Illinois, in a separate study, is promoting a fascinating biofuel alternative
 to both corn ethanol and switchgrass -- seaweed.  Recent efforts by the U.S. Marine Corps have heated up interested in algae- and seaweed-based biofuels.

The new study looks at how to speed up the slow process of fermenting red seaweed biomass to produce biofuel.  Currently Saccharomyces cerevisiae -- commonly named yeast -- is the leading candidate for fermentation as it has genes which code for proteins capable of digesting both galactose and glucose -- the two primary sugars in red seaweed.  However, wild-variety yeast "eats" glucose before it will eat galactose, making the fermentation process slow, and thus, ultimately, more expensive.

By introducing a new sugar transporter and enzyme that breaks down cellobiose at the intracellular level via a bit of gene splicing, the team was able to create a strain of yeast that simultaneously digests galactose and glucose, cutting the production time of red seaweed-derived biofuel in half.

Yong-Su Jin, an assistant professor of microbial genomics, compared the development "to a person taking first a bite of a cheeseburger, then a bite of pickle. The process that uses the new strain puts the pickle in the cheeseburger sandwich so both foods are consumed at the same time."

Professor Jin says that the pre-treatment process to break down seaweed into cellobiose -- glucose pairs -- and galactose is considerably less toxic than many of the potential processes to break down cellulose from terrestrial crops.  Furthermore, he says that red seaweed has several other advantage as well, including its higher biomass-per-unit-area density, its higher rate of carbon fixation than terrestrial biofuels crops, and its ability to grow in the sea, thus escaping land-space constraints.

The researcher selected the red variety (Gelidium amansii) of seaweed as it’s a fast-growing variety found in abundance in one very space-constrained region -- Southeast Asia.

The study on the work was published [abstract] in the peer-reviewed journal Applied and Environmental Microbiology
.  The study follows work earlier this year published [abstract] in PNAS, which saw Professor Jin's team introduce pathways for simultaneous digesting of xylose -- another plant sugar -- and cellobiose into a yeast strain.

Together the studies paint an interesting picture.  Switchgrass is potentially undesirable in arid regions and in space-confined regions.  However, many of these same regions border the sea.

So for regions like the Southeastern United States, Southeast Asia, the Middle East, and Japan, growing biofuels in the sea might be the wisest approach of all.



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No need for biofuels now!!
By TheEinstein on 8/31/2011 12:01:05 AM , Rating: 0
I read the opener at MichelleMalkin.com but here is the meat of it for the TL;DR crowd...

CERN has proven that clouds are formed by Cosmic Radiation (Something other scientists claimed, but Al Gore and crowd had them silenced).

Using the chamber described here (With a full sensor, not finding the press release at the moment, but I will eventually) http://public.web.cern.ch/public/en/res … UD-en.html they proved beyond ANY doubt clouds are formed by Cosmic Radiation.

What does this mean?

1) Cosmic Radiation is affected by our Sun's magnetic 'push'. This field fluctuates in strength due to Tidal and other factors. This means sometimes more, sometimes less Cosmic Radiation reaches earth (Jupiter has a big field as well and does play in somewhat).

2) Cosmic Radiation, as the test proved, is the one factor that makes water molecules in the upper atmosphere bind into cloud vapor.

3) Water Vapor in of itself is the BIGGEST factor in keeping heat in the Earth's Atmosphere... however Cloud's are the biggest factor in REDUCING the amount of heat that gets to the lower atmosphere (Bounces off the clouds and back out, also in cloud form they do not absorb a lot of heat compared to the molecules)

4) When we get a lot of Cosmic Radiation we get WET + COLD years. When we get less Cosmic Radiation we get DRY + HOT years.

5) There is a significant amount of variance that is possible. A heavy source of cosmic radiation can be on the opposite side of the sun for instance, while our side can be dry, or there can be a solar flare (which does have an effect), or the sun itself may be experiencing a change in its magnetic field. These changes can result in more, or less Cosmic Radiation for us. This can actually vary significantly... for instance, at night we are aimed one way, and at day another way.

I would like to note I have been claiming this as truth for at LEAST 3 years. Now CERN has gone and proven it. I have pointed at evidence that the information Global Warming (and climate change opportunists/fearmongers) have used it flawed (criminally at places) and no one from the left ever even tried to admit any portion can be

From www.Michellemalkin.com

quote:
The science is now all-but-settled on global warming, convincing new evidence demonstrates, but Al Gore, the IPCC and other global warming doomsayers won’t be celebrating. The new findings point to cosmic rays and the sun — not human activities — as the dominant controller of climate on Earth.

The research, published with little fanfare this week in the prestigious journal Nature, comes from über-prestigious CERN, the European Organization for Nuclear Research, one of the world’s largest centres for scientific research involving 60 countries and 8,000 scientists at more than 600 universities and national laboratories. CERN is the organization that invented the World Wide Web, that built the multi-billion dollar Large Hadron Collider, and that has now built a pristinely clean stainless steel chamber that precisely recreated the Earth’s atmosphere.

In this chamber, 63 CERN scientists from 17 European and American institutes have done what global warming doomsayers said could never be done — demonstrate that cosmic rays promote the formation of molecules that in Earth’s atmosphere can grow and seed clouds, the cloudier and thus cooler it will be. Because the sun’s magnetic field controls how many cosmic rays reach Earth’s atmosphere (the stronger the sun’s magnetic field, the more it shields Earth from incoming cosmic rays from space), the sun determines the temperature on Earth.


~~~~~~~~~~~

Thus we do NOT need biofuels until they can be done cheaper than oil!




By TheEinstein on 8/31/2011 12:01:58 AM , Rating: 3
RE: No need for biofuels now!!
By michael67 on 8/31/2011 2:30:42 AM , Rating: 2
Nice, but hows this relevant to making seaweed a bad alternative for fuel?

Can you pleas tell me how seaweed has baring on all this?


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