Solar Fuels: Making hydrocarbon fuels directly from CO2 and sunlight

July 6, 2015 | Jim Lane6

Drop-in Hydrocarbon fuels made directly by plants? Here. we look at the science and risks of turning an “ability” into an “industrial reality”.

It’s common knowledge that terrestrial plants (and many aquatic species) use carbon dioxide, water and sunlight to make the molecules they need — using a complex series of metabolic pathways established and controlled by their genetic code. And its common knowledge that there’s carbon in CO2 and hydrogen in water.

So, why don’t we teach plants to produce hydrocarbons, directly, usable for fuels and chemicals with which we power our industrial lives?

It’s an “oft-praised, not-so-oft-seen” alternative to using sugars, starches or oils — that is, the materials that plants produce, to make fuels, chemicals and materials. Turns out that cutting out the middle step and producing hydrocarbons out of the box is, as the Australians would say, “hard yakka” (tough sledding).

This is the goal which has animated Joule, a stealthy technology developer in Boston which has attracted legions of supporters and detractors — developing a system which photosynthetically grows a modified cyanobacteria that produces ethanol, diesel or jet-range molecules, or even a large array of renewable chemicals.

And lately, more researchers have been delving into the field.

Can it really be done?

For some time, researchers have known that the green algae knownas Botryococcus braunii are capable of accumulating huge quantities of hydrocarbons. In fact, as this “cool read” review of b. braunii states, “the best record was 86% of its dry weight for an algal sample harvested from a natural bloom.”

B. braunii’s magic? Ir has a knack for accumulating hydrocarbons in the “extracellular space” instead of “in the cytoplasm” — which is to say, it puts all the hydrocarbons on the driveway because the hall closet’s too small.

You might well ask, if a ton of b. brauniican contain up to 1720 pounds of hydrocarbons, or about 230 gallons of hydrocarbons for fuel, why aren’t we all driving around on it?

Three limitations. First, b. braunii makes a slightly complex form of hydrocarbon that needs to be “cracked down” to the fuel range.Second, no one has yet worked out a commercially-affordable production and harvesting system for algal fuels — companies like Algenol and Cellana say they are close to cracking that problem, but not with our friend b. braunii. Third, our friend here grows sloooooowly.

So work on the organism continues, but it inspires the question. Could other aquatic or even terrestrial plants ever be trained to directly produce a fuel?

To which the answer is, they already do — what we need to find is a way to make them produce it faster and in higher concentrations. Which is no simple task, as it turns out. That’s what Joule’s up to, more or less. In their case, they’ve done a lot of work to build an organism from the ground up.

So, how close are we and what are the limitations?

According to this impressive review which appeared earlier this year in Plant Biotechnology, the challenges are four:

a) improving photosynthesis efficiency
b) fine-tuning the MEP pathway
c) optimizing key terpene enzymes
d) designing proper storage strategies

Over at Joule, we seen some remarkable results reported on the first three fronts — with photosynthetic efficiency and biocatalysts.

According to a report last year, Joule has successfully engineered “a photosynthetic biocatalyst able to divert 95% of fixed carbon normally converted to biomass directly to fuel.”

Joule noted at the time: “Prior research has generally capped the photon energy conversion efficiency of photosynthetic processes at 2 – 3%. By contrast, Joule has applied a systems approach that spans biocatalyst, reactor and process engineering to negate the effects of these conditions, resulting in many-fold greater energy conversion efficiencies and supporting Joule’s estimated maximum of 14%.”

Storage? In most cases, we’ve seen researchers focus on secretion. That is, the cell won’t contain all the hydrocarbons we want to produce, so it’s secreted outside of the cell, ready for harvest. That’s the “milk the cow” rather than “shoot the cattle” approach to harvesting fuels from living cells. Algenol and Joule ar both working on that technology.

Joule, Algenol and their target molecules

Algenol’s demonstration system in Florida.

We know that Joule and Algenol are both producing ethanol — both have the capability to produce diesel-range molecules and other renewable chemicals, but we are not clear on the timelines and progress to date. Which is to say, they can make them, but we’re not clear on whether they can a) make them at commercial-feasible costs or b) make them at commercial-scale. Stay tuned on this channel.

The Joule system – a scaled process, as of October 2014, in Hobbs, NM.

Commercial-scale

Algenol and Joule are both expected to commence commercial-scale construction this decade — in the case of Algenol, we dont have a specific date; Joule says construction will commence in 2017.

What can be expected?

The sustainability equation. Though research into hydrocarbon production from terrestrial plants is ongoing, the timelines look long. And, we would expect that the Joule / Algenol approach, which uses non-productive land and non-potable water, is going to be the winner on sustainability hands down as long as the economics work.

So, think “photosynthetic organisms” for now, terrestrial plants maybe one day down the line, maybe never.

The CO2 equation. The systems that have been developed to date use direct CO2 fed from point sources. Think “climbing Mt. Everest” where the optimal result is from using a “bottled gas” supplement to make the trip. There’s been a lot of work on sequestering CO2 from the atmosphere — best we’ve seen is a mid-term target of $100 per ton, and with lower-cost CO2 available from point sources and plenty of it, it’ll to go that way, for now.

Who’s in the lead. For now, Joule and Algenol. But a growing cadre of researchers is working on this. We sure hope to see a highly-productive terpene-secreting organism one of these days. That really would be something.

Why make a $2 fuel when you can make a $5 chemical? The answer is simple, you make all the $5 chemicals you can, but one would rapidly run through all the available demand with a couple of scaled commercial faclities, in many cases.

The Bottom Line

Can it happen? It already does. Will it happen, industrially? A first-generation of the technology is expected in the next few years.

Gevo lands marine endorsement for isobutanol

By Gevo | June 18, 2015

• 
  Gevo's isobutanol plant at Luverne, Minnesota
  

Gevo Inc. has received a key endorsement for the use of its renewable isobutanol by the marine industry, following support and recommendation for the use of isobutanol by the National Marine Manufacturers Association as an effective, less damaging, more suitable biofuel alternative than ethanol for powering various types of marine and recreational boat engines.

The NMMA is the leading association representing the recreational boating industry in North America. Its member companies produce more than 80 percent of the boats, engines, trailers, accessories and gear used by boaters and anglers throughout the U.S. and Canada. Over the last five years, the NMMA has worked together with Gevo, the U.S. DOE, Argonne National Laboratory, the U.S. Coast Guard and others on the testing of isobutanol in a variety of marine engines. During this time, the NMMA has gathered a great amount of data supporting the viability of isobutanol as the preferred renewable fuel blendstock for gasoline-powered marine engines.

The studies showed that isobutanol fuel blends are a preferable power source for the marina markets. Isobutanol solves concerns that many boaters have with ethanol-blended fuels, which can damage internal engine parts. In the studies several advantages of isobutanol-blended fuel were apparent, including:

  -- Provides higher energy content;

  -- Prevents moisture absorption & phase separation; and

  -- Reduces engine corrosion.

 "We believe that the marine industry will be an important market for Gevo's isobutanol. The technical properties of isobutanol shine in this application. We appreciate the efforts and the collaboration between Gevo and the NMMA throughout the testing program. We are pleased to have provided, from our plant in Luverne, the isobutanol needed to make the 16% isobutanol blended fuels that the studies required, for both on-water tests and in the laboratory," said Dr. Patrick Gruber, Gevo CEO. "We are delighted with the results of the testing and to have the endorsement of the NMMA. Isobutanol has proven to be an effective, highly compatible biofuel for the recreational boating industry."

"Based on years of collaborative testing across the industry, biobutanol fuel blends, such as the ones provided by Gevo during our test program, are a safe and viable alternative to ethanol for use in recreational marine engines and boats up to 16.1 percent by volume," said Jeff Wasil, engineering manager, emissions testing, certification and regulatory development at BRP US Inc. (Bombardier Recreational Products), an NMMA member.

The formal announcement by the NMMA to endorse isobutanol as an industry-wide biofuel alternative comes as the fuel industry focuses on addressing the congressionally-mandated renewable fuel standard, which requires 36 billion gallons of renewable fuel to be blended into the gasoline supply by 2022. These events will help broaden the market for Gevo's isobutanol fuel technology, enabling Gevo to support recreational boating in its efforts to move towards alternative, renewable fuels and chemicals.

• 

  Image: iStock

  FULL SCREEN
• 

  Image: iStock

  FULL SCREEN

• Previous
• Next

Predicting sediment flow in coastal vegetation

Model could help engineers design erosion-prevention strategies in marshes, wetlands, aquatic forests.

Jennifer Chu | MIT News Office
June 16, 2015

Seagrass, kelp beds, mangroves, and other aquatic vegetation are often considered “ecosystem engineers” for their ability to essentially create their own habitats: Aquatic leaves and reeds slow the flow of water, encouraging sediments to settle nearby to form a foundation on which more plants can grow.

Such underwater forests provide shelter to hundreds of organisms, and can also protect shorelines from erosion. However, in the last few decades, large swaths of aquatic vegetation have disappeared around the world, including 100 million acres of wetlands, and thousands of acres of seagrass and kelp beds, in the United States.

In large part, sediment transport — how sediment flows through a region — determines the survival of coastal marshes and mangroves: Plant growth depends on the accumulation of sediment to the seafloor. When strong storms or currents carry sediment away, underwater forests can also wash away, exposing coastlines and riverbanks to erosion.

Now researchers at MIT have developed a simple model that can help scientists understand how and when sediments move through a region of aquatic vegetation, such as a wetland. The researchers say engineers may use this model to design better ways to restore seagrass, mangroves, and other underwater plant beds. For example, using the model, scientists may be able to identify locations where aquatic vegetation may be less prone to erosion.

“Wetlands are very important because they protect our coastal areas, but they are eroding,” says Qingjun Yang, a graduate student in MIT’s Department of Civil and Environmental Engineering. “With this, engineers can do modeling on how the stresses vary, and whether it would be helpful to plant vegetation here or there, based on the equation.”

Yang and her colleagues —Heidi Nepf, the Donald and Martha Harleman Professor of Civil and Environmental Engineering at MIT, and postdoc Francois Kerger — have published their results in the journal Water Resources Research.

Catching drift

To estimate sediment transport in aquatic environments, one key factor is what’s known as “bed shear stress” — the friction exerted by water at the seabed, which gives scientists an idea of how sediments move across the seafloor. Existing models and equations calculate bed shear stress for underwater environments without vegetation. However, there exist no applicable models for vegetated regions, as plants create more complicated currents and eddies, muddying the picture of sediment transport through such regions.

Yang and her colleagues sought to develop a model of bed shear stress for vegetated environments by first setting up a controlled experiment to simulate sediment transport through a simple, reed-like environment.

In a large, 10-meter recirculating water tank lined with a bottom layer of plastic, the researchers erected thousands of thin dowels to simulate sturdy, marsh-like reeds. They then deposited polymer particles in the water, and ran a pump to circulate water through the tank.

Using a technique called laser Doppler velocimetry, they aimed a pair of lasers into the tank at various depths and positions. The researchers used the lasers’ backscattering, or reflected light, to calculate the particles’ velocity at a particular location. As the particles were very small, their velocity was equal to that of the surrounding water parcels, or groups of water molecules. The researchers then converted velocity measurements into estimates of friction, or stress, between water parcels, and at the bed.

Shaping the seabed

After multiple trials, the researchers observed that the friction exerted by one water parcel on another resembled a linear function with depth: The deeper a water parcel, the more friction it experienced, with the most stress occurring at the bed. This linear relationship is contrast to a well-established theory of bed shear stress, called “the law of the wall” — a theory that has mostly been applied to nonvegetated regions, and that generally assumes that an aquatic environment exerts constant stress near the bed, regardless of depth.

Yang developed an equation for bed shear stress based on the linear stress observed in the group’s experiment. She then used the equation to successfully predict friction at the bed, based on the velocity of water parcels at any location above the bed.

Yang says the model is most relevant for environments with relatively smooth beds and emergent vegetation — long, thin plants, such as reeds, that extend from the seabed to the water surface.

“We can use this model to predict how much energy it takes for sediment to begin to flow, and how fast the flow has to be,” Yang says. “The faster the flow, the more friction is exerted on the bed, and the more the sediment begins to move. Then we know how the land will evolve, and how we can shape and design vegetation and soil so they can live on without much erosion.”

“As anyone can imagine, the presence of plants makes the flow patterns very complicated — we can only approach the problem from a statistical perspective, by modeling relevant statistics of the flow field through the plants,” says Francesco Ballio, a professor of civil engineering at the Polytechnic University of Milan who was not involved in the research. “This model can be already used for calculation of the flow field in vegetated water systems such as rivers and wetlands. … As a consequence, it may be incorporated also as a component of more complex eco-hydrodynamic models for water bodies management and restoration. But this will require some testing.”

This research was funded, in part, by the National Science Foundation.

FEEDING THE HUNGRY WITH MICROALGAE

Spirulina cultivation in Bangui, Central Africa Republic. Photo: Nutrition Santé Bangui

in Worldcrunch about a 72-year old French chef who has taken on the challenge of bringing spirulina to the malnourished youth of the Central Africa.

Freddy owns a restaurant, the Relais de Chasse (hunting lodge), a popular eatery in Bangui, the capital of the Central African Republic. He also works with an agricultural cooperative, hidden in the middle of luxuriant tropical vegetation, where the “miracle product” spirulina is made. Spirulina can get a child suffering from dietary deficiencies on his or her feet in just a matter of weeks.

In the local market spirulina sells for about 30 Euros per kilogram, and is a serious, natural and affordable alternative to the famous “Plumpy’nut,” a French-made sugar and peanut paste that is widely used by NGOs to fight against child rickets in developing countries.

Freddy comes from Brittany, in the northwest of France, but has spent almost half his life in Africa, single-handedly dealing with his small spirulina factory and a child nutrition center, where his “magic potion” is saving lives. Freddy himself swallows a large coffee spoon of it every morning, and welcomes his guests to do the same. It’s the secret, he says, to his own good health.

Freddy’s fascination for spirulina began in 1991, when he accommodated Dr. Jean Dupire, a general practitioner working for a local clinic. Dr. Dupire had just obtained two large barrels of spirulina that were supposed to go to Zaire, which was at war, but ended up by accident in Bangui. Locals didn’t know what to do with the barrels. But for the doctor, a nutrition specialist, they were a priceless treasure. He knew all about the virtues of this microalgae filled with proteins that also has most of the essential nutrients, and lacks only Omega-3 to be complete.

To treat the unfed children and compensate for the lack of Omega-3, the doctor developed a “spirulina-fish” formula. The results have been nothing short of spectacular. “In one month, a child suffering from severe malnutrition is back on his feet,” says Dr. Dupine, who plans to expand the model by training doctors and producers.

Algal genes advancing pacemaker technology

June 22, 2015
Kevin Hattori

Technion researchers have successfully established a new approach for pacing the heart and synchronizing its mechanical activity without the use of a conventional electrical pacemaker. This novel biologic strategy employs light-sensitive genes that can be injected into the heart and then activated by flashes of blue light.

Professor Lior Gepstein

More than 3 million people worldwide have had electronic pacemakers implanted. The most common indication for a pacemaker is the treatment of a slow heart beat which can put patients at risk for fainting, heart failure, and even death. Pacemakers work by sending electrical signals to the heart to regulate the heart beat. Pacemakers can also be used for cardiac resynchronization therapy (CRT), an approach aiming to synchronize the contraction of the heart’s two ventricles in order to improve heart function, symptom status and decrease mortality in some patients who suffer from heart failure.

The new optogenetic approach for cardiac pacing and resynchronization was developed by Prof. Lior Gepstein and Dr. Udi Nussinovitch of the Technion-Israel Institute of Technology’s Rappaport Faculty of Medicine, and Rambam Medical Center.

“Our work is the first to suggest a non-electrical approach to cardiac resynchronization therapy,” Gepstein said. “Before this, there have been a number of elegant gene therapy and cell therapy approaches for generating biological pacemakers that can pace the heart from a single spot. However it was impossible to use such approaches to activate the heart simultaneously from a number of sites for resynchronization therapy.”

If the biological pacemaker can be adapted for humans, it could help patients avoid many of the drawbacks of electrical pacemakers. These include the surgical procedure needed to implant the device, the risk of infection, the limitation on the number and locations of the pacing wires used, the possible decline in cardiac function resulting from the change in the normal electrical activation pattern, and the limitations on implantation in children.

“This is a very important proof-of-concept experiment, which for the first time, demonstrates a mechanism to pace the heart without the need for wires and allows for simultaneous pacing from multiple sites,” said Dr. Jeffrey Olgin, chief of the Division of Cardiology and co-director of the Heart and Vascular Center at the University of California, San Francisco. “The most common site of failure of current pacemakers are the leads or wires that connect the heart muscle to the electrical impulse. The approach demonstrated in this paper has the potential to eliminate these wires or have a single lead excite multiple sites simultaneously.”

Pacing the heart with light is part of the emerging field of optogenetics, which has gained considerable momentum in the field of brain research. Researchers working in the field have been taking light-sensitive genes from algae and placing them in cells where they act like a switch, turning certain behaviors on or off when the cells are exposed to pulses of light.

As they report in the journal Nature Biotechnology, the Technion researchers injected one of these algae genes (channelorhodopsin-2) into a specific area of rat heart muscle. The scientists then showed that the light-sensitive protein expressed at this site could be turned on with flashes of blue light and drive the heart muscle to contract. By altering the frequency of the flashes, Gepstein and Nussinovitch could control and regulate the heart rate. They went on to deliver the gene to several places in the heart’s pumping chambers, and demonstrated the ability to simultaneously activate the heart muscle from many places in an effort to synchronize the heart’s pumping function.

Scientists will need to do more research for this optogenetic-based pacemaker strategy to become a reality in human health, Gepstein said. For instance, the gene injected in the rat experiments is sensitive to blue light which has poor tissue penetration potentially limiting its utility in large animals or humans.

“This means that the affected cells have to be relatively superficial–near the surface of the heart–and that an optical fiber should be implanted bringing the illumination beam as close as possible to the cells,” Gepstein said. “A potential solution in the future may be the development of similar light-sensitive proteins that will be responsive to light in the near-red or even infra-red spectrum, which penetrates tissue much better, allowing illumination from a long distance.”

The Technion-Israel Institute of Technology is a major source of the innovation and brainpower that drives the Israeli economy, and a key to Israel’s renown as the world’s “Start-Up Nation.” Its three Nobel Prize winners exemplify academic excellence. Technion people, ideas and inventions make immeasurable contributions to the world including life-saving medicine, sustainable energy, computer science, water conservation and nanotechnology. The Joan and Irwin Jacobs Technion-Cornell Institute is a vital component of Cornell NYC Tech, and a model for graduate applied science education that is expected to transform New York City’s economy.

American Technion Society (ATS) donors provide critical support for the Technion—more than $2 billion since its inception in 1940. Based in New York City, the ATS and its network of chapters across the U.S. provide funds for scholarships, fellowships, faculty recruitment and chairs, research, buildings, laboratories, classrooms and dormitories, and more.

Anaerobic Digestion News: 10 Easy Biomethane Lessons

Anaerobic Digestion News: 10 Easy Biomethane Lessons: Lesson 1. The Real Biomethane Definition The definition of biomethane is quite a difficult one, because there are competing definitions....

Anaerobic Digestion News - What is Biogas?

Anaerobic Digestion News - What is Biogas? - Its Chemical Composition and Upgrading and Compression... - rpj1941@gmail.com - Gmail