Hydrates are a water ice and usually a natural gas compound that have been explored by researchers as a source of alternative fuel or storage medium for CO2.  The PNNL researchers note at first discovery the hydrogen storage value approaches the goal of a Department of Energy standard and could make hydrogen hydrates practical and affordable for storage.

Using computer analysis of the ice and gas compound reveals key details of its structure and researchers have accurately quantified the molecular-scale interactions between the gases of either hydrogen or methane, also known as natural gas – and the water molecules that the form cages around them.

The research team’s results from the Department of Energy’s Pacific Northwest National Laboratory were published in Chemical Physics Letters online December 22, 2011.

While hydrogen is the most interesting use of hydrates, PNNL chemist Sotiris Xantheas the lead author said, the results could also provide insight into the process of replacing methane with carbon dioxide in the naturally abundant “water-based reservoirs.”

Here’s the marvel revealed in the research as put by Xantheas, “Current thinking is that you need large amounts of energy to push the methane out, which destroys the scaffold in the process. But the computer modeling shows that there is an alternative low energy pathway. All you need to do is break a single hydrogen bond between water molecules forming the cage – the methane comes out, and then the hydrate reseals itself.”  This revelation has major implications on natural gas recovery.

Previously Xantheas and the colleagues used computer algorithms and models to examine the water-based, ice-like scaffold that holds the gas. Water molecules form individual cages made with 20 or 24 molecules. Multiple cages join together in large lattices. But those scaffolds were empty in the earlier analysis.

To find out how fuels can be accommodated inside the water cages, Xantheas and colleague Soohaeng Yoo Willow built computer models of the cages with either hydrogen gas – in which two hydrogen atoms are bound together – or methane gas, a small molecule made with one carbon and four hydrogen atoms.

In the hydrogen hydrates, the idea that could potentially be used as materials for hydrogen fuel storage, a small hollow cage made from 20 water molecules could hold up to a maximum of five hydrogen molecules and a larger cage made from 24 water molecules could hold up to seven.

The maximum storage capacity equates to about 10 weight-percent, or the percentage of hydrogen by mass in the chunks of ice.

However packing hydrogen in that tight puts undue strain on the system.  But it nearly doubles the DOE’s goal for hydrogen storage above a 5.5 weight-percent.

Now the story gets intuitive, innovative and just clever.  Experimentally, hydrogen storage researchers typically measure much less storage capacities. The computer model showed them why: The hydrogen molecules tended to leak out of the cages, reducing the amount of hydrogen that could be stored.

The PNNL team found that adding a methane molecule to the larger cages in the pure hydrogen hydrate prevented the hydrogen gas from leaking out. The computer model showed the researchers that they could store the hydrogen at high pressure and practical temperatures, and release it by reducing the pressure, which melts it.

Understanding how the gas interacts and moves through the cages can help chemists or engineers store gas and remove it at will.

Willow and Xantheas’ computer simulations showed that hydrogen molecules could migrate through the cages by passing between the figurative bars of the water cages. However there’s a problem to work out, the cages also had gates: Sometimes a low-energy bond between two water molecules broke, causing a water molecule to swing open and let the hydrogen molecule drift out. The “gate” closed right after the molecule passed through to reform the lattice.

With methane hydrates, some fuel producers want to remove the gas safely to use it.  So, Willow and Xantheas tested how methane could migrate through the cages.

The water cages are only big enough to comfortably hold one methane molecule, so the chemists stuffed two methane molecules inside and watched what happened. Quickly, one of the water molecules forming the cage swung open like a gate, allowing one methane molecule to escape. The gate then slammed shut as the remaining molecule scooted into the middle of the cage.

Xantheas explains, “This process is important because it can happen with natural gas. It shows how methane can move in the natural world. We hope this analysis will help with the technical issues that need to be addressed with gas hydrate research and development.”

The team’s work is still all in the computer, but the insight should allow a broad spectrum of researchers a blueprint for experimentation and the beginning steps of processes and engineering.  The best news is the storage rate is very high and the temperatures are in an easy to access zone with common refrigeration and low energy requirements to do the warm up.  The engineering challenge to today is substantial, but some very good minds are going to light up with this news.

The Very Large Unmangaged Mexico City Landfill. Its a huge resource waiting for use. Click image for the largest view.

Now new research from North Carolina State University points to one species of microbe that  is paving the way for other methane producers.  The starting bug has been found. That opens the door to engineering better landfills with better production management.  Imagine a landfill with real economic prospects beyond getting the trash out of sight.

The NCSU researchers found that an anaerobic bacterium called Methanosarcina barkeri appears to be the key microbe.

Methanosarcine Barkeri Colony Culture. Click image for the largest view.

Dr. Francis de los Reyes, an associate professor of civil engineering at NC State and co-author of a paper describing the research explains how the research got its start, “Landfills receive a wide variety of solid waste, and that waste generally starts out with a fairly low pH level. The low pH level makes it difficult for most methanogens – methane-producing organisms – to survive. We started this project in hopes of better understanding the mechanism that raises the pH level in landfills, fostering the growth of methanogens.”

What the NCSU researchers found was M. barkeri – a hearty methanogen that can survive at low pH levels. M. barkeri’s role is to consume the acids in its environment, producing methane and increasing the pH levels in its immediate area. This, in turn, makes that area more amenable for other methanogens.

Simplified Landfill Diagram. Image credit earth911.com.

Water; usually a problem to keep out of landfills – is key.  As the moisture leaches through the landfill, it spreads those high pH levels – making other parts of the landfill habitable for M. barkeri and other methane-producing microbes. M. barkeri then moves in and repeats the process, leaving neutral pH levels – and healthy populations of other methanogens – in its wake.

M. barkeri and its methanogen cousins produce large quantities of methane, and as methane is a powerful greenhouse gas, landfill methane leaks could be bad news for the environment. Methane can be, and often is, collected at landfill sites and used for power generation. With the NCSU research the basic tool to exploit problem is available opening the door to much more and better exploitation.

Another payoff is the methanogens break down the solid organic waste as they go, compacting it so that it takes up less space.  If the research gets to the obvious end, landfills themselves might be mined for the inorganics matrerials and then reused again.  That would be a huge relief for everyone with a moment to think about it.

It may well happen more quickly as Dr. de los Reyes explains, “The research community can use our findings to explore ways of accelerating the methane-generation process creating methane more quickly for power generation, and making additional room in the landfill for waste disposal.”

Here’s the paper’s title and link.  “Effect of Spatial Differences in Microbial Activity, pH, and Substrate Levels on Methanogenesis Initiation in Refuse,” will be published in the April issue of Applied and Environmental Microbiology. The paper was co-authored by Dr. Bryan Staley, who did the work while a Ph.D. student at NCSU; de los Reyes; and Dr. Morton Barlaz, professor and department head of civil, construction and environmental engineering at NCSU.

Waste Management, Inc. and the Environmental Research and Education Foundation funded the research.  For that, and the expectation that cleaning up will look like a better more earth friendly thing to do, we are thankful. Keep those funds coming and lets hopes the technology gets to work quickly.  Your humble writer finds landfills necessary but dreadful necessities that deserve a path to productivity.

When they first saw the data, environmental chemist Tonya Del Sontro and her PhD supervisor Professor Bernhard Wehrli were skeptical. But the unexpectedly high values stood up to careful analysis: On average, daily emissions of methane (CH4) from Lake Wohlen amount to more than 150 mg per m2 surface area. This is by far the highest emission rate recorded to date for a temperate reservoir. At a summer water temperature of 17°C the rate is twice as high, which makes it comparable to the emission rates observed for tropical reservoirs.

Del Sontro Checking Methane Results in Lake Wohlen. Click image for the largest view.

Overall, the Lake Wohlen reservoir on the river Aare produces 150 metric tons of methane a year. This is about the same amount as is emitted annually by around 2000 cows, which are for the global warming crowd a nemeses to the atmosphere.  In more sensible terms 150 metric tons could be equivalent the CO2 emissions or fuel needs over 25 million cars kilometers or 15.5 million miles. Wohlen isn’t even that big of a lake.

This is worthwhile news.  The careful observer knows that methane is an abundant naturally produced fuel, the sources of which are just getting explored.  For the Swiss Institute’s researchers the funding might have come from the global warming scheme.  Del Santos said, “So hydropower isn’t quite as climate-neutral as people have assumed in the past,” in a reference to hydropower dammed reservoirs.  Little does she seem to know or the press release writer that one way or another the microbes are going to get that organic matter, dam or not.

At the same time, she does not wish to dramatize the findings of her research: even if the Aare river hydropower plant is taken to be responsible for all the methane emissions from the reservoir, and these are expressed in CO2-equivalents, a coal-fired power station with the same output produces 40 times as much CO2. However, the emissions from Lake Wohlen do indicate that run-of-the-river reservoirs can also be significant sources of methane emissions in temperate regions. As Professor Wehrli notes, “That’s something which has previously been overlooked in greenhouse gas budgets.”  It’s a great resource if someone can catch the methane before is goes to the atmosphere.  150 metric tons equals 165 standard tons, about eight semi-truck trailer loads by weight. Keep in mind that a therm gained by methane vs coal gives off a lot less CO2, too.

The methane production in Lake Wohlen is attributable to organic matter transported by the Aare River from Lake Thun and the rest of the drainage basin. In the reservoir, the organic matter settles rapidly, undergoing microbial fermentation in the sediments. “In the summer,” says Del Sontro, “the water in Lake Wohlen sometimes looks like champagne, with masses of gas bubbles rising to the surface.” To study these bubbles, the Eawag scientists used custom-made gas traps in the form of inverted funnels. The analyses revealed that they were mainly composed of methane.

Del Sontro Loading Methane Collector. Click image for the largest view.

That might be an idea for a diversion to collect the run off and gather the organic matter for a process to make methane for use and retuning cleaner water to the river.

During the winter, due to the cold temperatures, methane emissions are minimal. According to Wehrli, this explains why climate researchers have previously focused largely on the huge reservoirs lying in tropical regions where, temperatures are warm throughout the year, and inundated forest areas provide a large supply of nutrients for microbes. Likewise, low water temperatures and low nutrient inputs mean that large Alpine reservoirs do not give rise to significant methane emissions. The researchers now plan to study other run-of-the-river reservoirs on the Central Plateau so as to determine whether Lake Wohlen is a special case, or whether methane budgets need to be revised for Switzerland as a whole.

Odds are that Lake Wohlen isn’t special other than the surprise value of high altitude and low temperature.  But the research does beg certain questions.  First would be the organic value of say the Mississippi River in Louisiana.  The Mississippi is rich in organics and fertility and should be a stunningly large source of raw material. The second question could be is there an economical way to harvest the organics and process to methane products for sale.  The third then would be what state in the drainage basin is going to let all that get to Louisiana when they realize what’s going on.

Sometimes the global warming folks just can’t help themselves.  There are rare instances of the money spent revealing a new opportunity.  This writer can’t help but smile over this one.

Del Sontro’s full paper is available here as a pdf download.

The team uses methane, the primary component of natural gas, a plentiful and an attractive fuel and raw material for chemicals because it is more efficient than oil, produces less pollution and could serve as a practical substitute for petroleum-based fuels until renewable fuels are widely useable and available.  Note that making methane from biomass isn’t particularly difficult.  The research could lead to a new step in a process of biomass to fuels.

Methane Model With 3D Balls. Click image for the largest view.

Methane’s main disadvantages are its difficult and costly to transport because it remains a gas at temperatures and pressures typical on the Earth’s surface, requiring dedicated pipelines to get it to markets and highly pressurized and cooled tanks for storage.

The UW and UNC scientists have found a step for devising a way to convert methane to methanol or other liquids that can easily be transported, especially from the remote sites where natural gas is often found. The huge investments in natural gas production are becoming more of the liquefaction effort to make the gas transport ready.

The team’s findings are published in the Oct. 23 issue of the journal Science.

Methane is so attractive and valued because of the molecule’s high-energy single carbon and four hydrogen atom bonds. Methane doesn’t react easily with other materials, so it is most often simply burned as fuel. Oxidizing breaks all four hydrogen-carbon bonds and produces carbon dioxide and water, said Karen Goldberg, a UW chemistry professor in the UW news release introduction.

Goldberg explains converting methane into useful chemicals, including readily transported liquids, currently requires high temperatures and a lot of energy. Catalysts that turn methane into other chemicals at lower temperatures have been discovered, but they have proven to be too slow, too inefficient or too expensive for industrial applications.  Binding methane to a metal catalyst is the first step required to selectively break just one of the carbon-hydrogen bonds in the process of converting natural gas to methanol or another liquid.

The research paper describes the first observation of a metal complex (a compound consisting of a central metal atom connected to surrounding atoms or molecules) that binds the methane in solution. This compound thus serves as a model for other possible methane complexes. Within the complex, the methane’s carbon-hydrogen bonds remained intact as they bound to a rare metal called rhodium.

Goldberg says, “The idea is to turn methane into a liquid in which you preserve most of the carbon-hydrogen bonds so that you can still have all that energy. This gives us a clue as to what the first interaction between methane and metal must look like.”

Maurice Brookhart, a chemistry professor over at UNC said the carbon-hydrogen bonds are very strong and hard to break, but in methane complexes breaking the carbon-hydrogen bond becomes easier.  Brookhart says, “The next step is to use knowledge gained from this discovery to formulate other complexes and conditions that will allow us to catalytically replace one hydrogen atom on methane with other atoms and produce liquid chemicals such as methanol.”

Methanol Model With 3D Balls, Click image for the largest view.

The team’s work should spur further advances in developing catalysts to transform methane into methanol or other liquids, Goldberg said. She noted that actually developing a process and being able to convert the gas into a liquid chemical at reasonable temperatures still is likely some distance in the future.  But it’s still substantial progress.

The lead author of the paper is Wesley Bernskoetter, who is now at Brown University, did the work while at UNC. Goldberg, Brookhart and Cynthia Schauer, associate chemistry professor at UNC, are the co-authors.

The work comes out of a major National Science Foundation-funded collaboration, the UW-based Center for Enabling New Technologies Through Catalysis, directed by Goldberg, that involves 13 universities and research centers in the United States and Canada, including UNC. The Center’s goal is aimed at finding efficient, inexpensive and environmentally friendly ways to produce chemicals and fuels. Additional funding came from the National Institutes of Health.

When you think about methane, one reaches out much further than natural gas.  The climate change crowd rails about cattle belches, farts and manure emissions, but all animals are sourcing methane to the atmosphere, some of which could be captured.  That can include the vent over every restroom and bathroom, the sewers, water treatment plants and landfills.  The total methane availability is stunning.

A low temperature catalyst available to install across the spectrum of sources would make a lot of fuel available.  Products are already coming; Toshiba Corp has launched the company’s first direct methanol fuel cell (DMFC) product, the Dynario, as an external power source that delivers power to mobile digital consumer products.

Dynario Toshiba's First DMFC Product.

With an injection of methanol solution from its dedicated cartridge, Dynario starts to generate electricity that is delivered to a digital consumer product (i.e. a mobile phone or a digital media player) via a USB cable. On a single refill of methanol, which can be made in an around 20 seconds, Dynario can generate enough power to charge two typical mobile phones.

This writer would love to escape the cell phone charger with a squirt of methanol.  The technology is coming and the UW and UNC research team has made a significant discovery to get the fuel production process ready.

As a natural gas production or as a storage form of renewable electricity production, this is surely a marketplace disruptive event. The team’s experiments led to an 80% low efficiency rating – which for storage from renewables would be tolerable.

The story from the Penn State press release on finding the serendipitous innovation as Logan puts it, “We were studying making hydrogen in microbial electrolysis cells and we kept getting all this methane. We may now understand why.”

Methanogenic microorganisms produce methane in marshes and dumps, but scientists have thought that the organisms turned hydrogen or organic materials, such as acetate, into the methane. However, the Logan team found, while trying to produce hydrogen in microbial electrolysis cells, that their cells produced much more methane than expected.

“All the methane generation going on in nature that we have assumed is going through hydrogen may not be,” said Logan. “We actually find very little hydrogen in the gas phase in nature. Perhaps where we assumed hydrogen is being made, it is not.”

In the initial experiment with microbial electrolysis cells an electrical voltage is required to be added to the natural voltage produced by bacteria using organic materials to produce current that produces the hydrogen. The team learned that the Archaea microbe, using about the same electrical input, could use the current to convert carbon dioxide and water to methane without any organic material, bacteria or hydrogen usually found in microbial electrolysis cells. There’s your “eureka!” moment. Must make the wind and solar storage folks and the global CO2 controllers smile.

The result – Logan puts it plainly, “We have a microbe that is self perpetuating that can accept electrons directly, and use them to create methane.” It’s almost unnerving in its simplicity.

Penn State's Logan Cheng and Xing. Click image for more info.

This innovation is obviously going places so lets get the team members named on the post. They are Shaoan Cheng, senior research associate; Defeng Xing, post doctoral researcher, and Douglas F. Call, graduate student, environmental engineering. Congratulations! It’s a great example of research investing coming up with something off the original mark, yet extremely worthwhile and valuable.

The finer details are the team created a two-chambered cell with an anode immersed in water on one side of the chamber and a cathode in water, inorganic nutrients and carbon dioxide on the other side of the chamber. They applied a voltage, but recorded only a minute current. The researchers then coated the cathode with the biofilm of Archaea and not only did current flow in the circuit, but the cell produced methane.

Logan says, “The only way to get current at the voltage we used was if the microbes were directly accepting electrons.” Another key he notes, is the electrochemical reaction takes place without any precious metal catalysts and at a lower energy level than converting carbon dioxide to methane using conventional, non-biological methods. Maybe it really will be a cheap technology.

If the electricity comes from a non-carbon source such as wind or solar power they’d be carbon neutral. The process doesn’t sequester carbon; it recycles it into new fuel. If the carbon is recaptured in each cycle it stays carbon neutral.

Logan reminds gently that methane is preferred over hydrogen because a large portion of the U.S. infrastructure is already set up to easily transport and deliver methane. He also notes it would be a great way for off peak capture of renewable energy into transport, home heating, commercial, and industrial fuel.

The quick sensation is that producers of CO2 suddenly have a revenue source instead of a cap and tax problem if they so choose.

Are we really sure we want to lose all that CO2 to sequestration?

Might want to think that through without the global warming hysteria bringing such damning bias to the science.

Go guys! And thanks to the National Science Foundation and Air Products and Chemicals, Inc. who provided the project support.

Photocatalytic Converter CO2 & H2O to Hydrocarbons. Click image for more.

The Penn State researchers at the Department of Electrical Engineering and Materials Research Institute use dual catalysts to efficiently turn carbon dioxide and water vapor into methane and other hydrocarbons using titania nanotubes in a process using solar for the energy source. Chemically converting water and carbon dioxide to methane seems simple on paper — one carbon dioxide molecule and two water molecules become one methane molecule and two oxygen molecules. But the energy needed for the reaction to occur is at least eight photons for each produced molecule.

In the Nano Letter paper the team notes, “Recycling of carbon dioxide via conversion into a high energy-content fuel, suitable for use in the existing hydrocarbon-based energy infrastructure, is an attractive option, however the process is energy intense and useful only if a renewable energy source can be used for the purpose.”

Grimes says in the Penn State news piece, “Converting carbon dioxide and water to methane using photocatalysis is an appealing idea, but historically, attempts have had very low conversion rates. To get significant hydrocarbon reaction yields require an efficient photocatalyst that uses the maximum energy available in sunlight.”

The dual catalyst describes as titanium dioxide nanotubes doped with nitrogen and coated with a thin layer of both copper and platinum to converts a mixture of carbon dioxide and water vapor to methane. The serious results are using visible outdoor light; they are reporting a 20-times higher yield of methane than previously published attempts conducted in laboratory conditions using intense ultraviolet light exposure.

The team used natural sunlight to test their nanotubes in a chamber containing a mix of water vapor and carbon dioxide. They exposed the co-catalyst sensitized nanotubes to sunlight for 2.5 to 3.5 hours when the sun was producing between 102 and 75 milliwatts for each square centimeter exposed.

The research story is nanotubes annealed at 600 degrees Celsius and coated with copper yielded the highest amounts of hydrocarbons and that the same kind of nanotubes coated with platinum actually yielded more hydrogen, while the copper coated nanotubes produced more carbon monoxide. Both hydrogen and carbon monoxide are normally occuring intermediate steps in the process and as the building blocks of syngas, can be used to make liquid hydrocarbon fuels.

The team then built a nanotube array with about half the surface coated in copper and the other half in platinum, they enhanced the hydrocarbon production and eliminated carbon monoxide. The yield for these dual catalyst nanotubes was 163 parts per million of hydrocarbons an hour for each square centimeter. The yield from titania nanotubes without either copper or platinum catalysts is only about 10 parts per million, or a 16.3 fold increase in productivity using the dual catalyst innovation.

Grimes adds, “If we uniformly coated the surface of the nanotube arrays with copper oxide, I think we could greatly improve the yield.”

This is a ‘first result’ kind of breakthrough. The team learned that lengthening the titanium dioxide tubes, which for other applications increases yield, does not improve results. “We think that distribution of the sputtered (the method of spreading) catalyst nanoparticles is at the top surface of the nanotubes and not inside and that is why increased length does not improve the reaction,” says Grimes.

The most practical news is that the catalysts shifted the reaction from one that used only the energy in ultraviolet light to one that used other wavelengths of visible light and therefore more of the sun’s energy. This is a very significant innovation.

There is a great deal to do in this field with Penn State leading the way now. The research team is now working on converting their batch reactor into a continuous flow-through design that they believe will significantly increase yields.

Methane is already an accelerating fuel market with the U.S. military deploying fuel cells, more marketing and political efforts to convert personal transport to methane or natural gas and the Pickens Plan pressing for substituting methane products for oil imports.

These points all make clear that the Penn State team’s effort is much more significant than most people realize. I’m duly impressed and wish to send along a congratulatory thought to Craig Grimes, Oomman K. Varghese and Maggie Paulose, Materials Research Institute research scientists and Thomas J. LaTempa, graduate student in electrical engineering.

Today methane is simply compressed or compressed and chilled to a liquid state. The compression is usually to 3000 psi on up to 4000 psi. To get to the liquid state the compression is light, about 3.6 psi and cooled to –260 degrees F or -163 degrees C. Compression can get better than 1/100^th the volume. Liquefied methane gets to 1/600^th the volume of free gas. Those ratios of volume are important.

Tanks are enclosed volumes. The 20 gallon gasoline tank isn’t especially large and holding a liquid it can be molded to fit cavities so making good use of an available volume. But when you get pressured up the tanks need cylindrical shapes with spherical ends to keep the materials used minimized so controlling the cost. That’s when the volume within a vehicle becomes an issue. They must be integrated early in design to avoid foregoing some other features.

The U.S Department of Energy has a storage goal stated as 180 v/v or standard temperature and pressure equivalent volume / volume of the absorbing material. Roughly speaking the USDOE number is 1/180 or so. With that in mind we can make some sense of the year’s research so far in new technologies for storage.

The next issue to address is the cost of tanks. The 20-gallon gas tank would only cost a few dollars. As progress is made on Compressed Natural Gas tanks the cost will come down, but for today we’ll look at cost issues and volume effectiveness. The last aspect in the cost issue will be the difference between CNG, gasoline and diesel at fill up. With prices wavering about with such volatility and the vast differences from location to location for natural gas prices, an old number of natural gas being about 2/3rds or so the cost of gasoline or diesel can be used. So, a more expensive tank can be expected, and to some as yet unknown extent, justified.

Route from Corncob to Stored Methane

Intuitively, the low cost leader might be the University of Missouri-Columbia and Midwest Research Institute in Kansas City created carbon briquettes with complex nanopores capable of storing natural gas at an unprecedented density of 180 times their own volume and at one-seventh (about 500 psi) the pressure of conventional natural gas tanks. 500 psi could be low enough to make more adaptive shapes. The raw material is corncobs, the center cylinder of the corn plant that holds the kernels as they grow. Currently they are usually just pitched out the back of the farmer’s combine as the kernels are harvested. This has to be a cheap resource that has collection and transport costs before the processing into the briquettes.

Peter Pfeifer of MU says “We are very excited about this breakthrough because it may lead to a flat and compact tank that would fit under the floor of a passenger car, similar to current gasoline tanks. Such a technology would make natural gas a widely attractive alternative fuel for everyone.” Pfeifer believes the absence of such a flatbed tank has been the principal reason why natural gas, which costs significantly less than gasoline and diesel and burns cleaner, is not yet widely used as a fuel for vehicles.

“Our project is the first time a carbon storage material has been made from corncobs, an abundantly available waste product in the Midwest,” said Pfeifer. “The carbon briquettes are made from the cobs that remain after the kernels have been harvested. The state of Missouri alone could supply the raw material for more than 10 million cars per year. It would be a unique opportunity to bring corn to the market for alternative fuels–corn kernels for ethanol production, and corncob for natural gas tanks.”

A test pickup truck, part of a fleet of more than 200 natural gas vehicles operated by Kansas City, has been in use since mid-October. The researchers are monitoring the technology’s performance, from mileage data to measurements of the stability of the briquettes and have started work on the next generation of briquettes to store more at lower briquette production costs.

A Methane Cage of Nano-sized Crystals

Hong-Cai Zhou and colleagues at Miami University published a report describing development of a new type of MOF (metal organic frameworks), called PCN-14, (porous coordination network) that has a high surface area of over 2000 m²/g. Laboratory studies show that the compound, composed of clusters of nano-sized cages, has a methane storage capacity 28 percent higher than the DOE target (230.4 v/v), a record high for methane-storage materials. Published in the Jan. 23 issue of ACS’ Journal of the American Chemical Society the costs are not explored, although the temperature and pressure are at standard. Note that this solution would be 38% of liquid without pressure or chilling. The costs are well worth exploring in this idea too.

Dry Water - Composition Graphic - Time to Capacity

In a report in Nature News, Andrew Cooper and his colleagues at the University of Liverpool, UK, have found that they can trap methane in a bizarre material dubbed ”dry water”, a mixture of silica and water that looks and acts like a fine white powder. The methane reacts with the water to produce a crystalline material called methane gas hydrate, in which individual methane molecules sit inside ice-like cages of water molecules. A liter of methane gas can be stored in about 6 grams of the material that they say, is very close to the target set by the US Department of Energy. This material is sourced from silica, the base material of sand helping to make this method economical relative to other, more exotic potential methane-capture materials.

This looks great, but the reality check is the density of the fuels. Natural gas would I suspect, needs cleaned to be stored by these tanking systems all the way to near pure methane, a not particularly difficult or costly enterprise but one that yields about 87% of the original natural gas. The other products like ethane and propane are valuable hydrocarbon products as well. Nor is there discussion about the price to get methane in and out of these solutions.

Methane is only 1,000 BTUs per standard cubic foot, so needing 125 cubic feet to equal the BTUs of one gallon of gasoline. But the volume of a gallon tank to the volume of a cubic foot is 1/7.48 – a 7.5 to 1 volume increase to maintain the total energy on board. So a 180 v/v storage solution (about a 50% increase in methane to volume) would be about a 1 of 5 reduction in range for the same tank volume. Or the 20-gallon gas tank replaced by methane at 180 v/v would be equal to 4 gallons of gasoline. Even at the liquid state, methane isn’t equal to gasoline. We’re going to have to get used to stopping to fill more often.

This will work. In the U.S. natural gas has a historic price advantage to gasoline. Methane is abundant, can be found, made, scavenged, and converted from oil. Even more important over time is that methane makes a fine fuel cell fuel. Swap out that internal combustion engine for a fuel cell and there might be a 3, 4 or better multiple of efficiency. If methane can be marketed at a 1/3 lower cost than gasoline, and be used four times as efficiently, the cost per mile compared to gasoline will be very low indeed.

It is. And there is a lot more to come.

Recently Mr. Pickens and his Plan make the case that natural gas, aka methane, could be used to displace imported oil for fueling personal light vehicles such as cars. The CEO of Chesapeake Energy, Aubrey K. McClendon, the U.S.’s largest producer of natural gas has hooked up to the Pickens Plan with advertising called CNG Now to promote more gas use. (CNGNOW.org) There are uncounted microorganisms that make methane, huge supplies of organic material to make it from and as hydrocarbons go, methane is the easiest to live with from pollution perspective. The shale natural gas, the tight sands natural gas, and the methane hydrates if they can be gathered pose an incredible supply beyond what’s in proven reserves are now. Natural gas will be with us for a very long time.

So when Oklahoma University researches working to root into the microorganisms that eat pipelines form the inside out found that these microorganisms could live in depleted oil reservoirs and convert unattainable oil into harvestable natural gas, I just have to look a little deeper.

There are in excess of 500,000 miles of petroleum pipeline in the U.S. The problem of leaks comes from the bit of water that comes along with crude production and the proportion has grown and is growing constantly as more water is used for enhanced recovery and comes along with oil production. It was long thought that anaerobes didn’t grow without oxygen, but that’s been proved wrong, microbes are quite good at life without oxygen. This is leading to laboratory research by 14 OU experts across the spectrum of the field. While the driver is the destruction of pipelines, the clue that microorganisms could be fed into old reservoirs and restart hydrocarbon production promises a big payoff.

Two thirds is the minimum expressed number of the oil remaining in place from known U.S. oil reserves. That’s a great deal of hydrocarbon available for reworking into methane. It also offers another way to relieve the pressure on oil for transport use. If OU can get a working organism to seed oil reservoirs the number of jobs, good return on investments, and energy security for the U.S. economy would be need only good rates of oil conversion to be a great benefit. The re-creation of oil patch and the good jobs and healthy economy would cover a wide swath of America.

The microorganisms are already known to work. OU is already looking into other kinds of reservoirs such as oil shale and other unconventional oil deposits.

From a beginning of trying to grasp the biological aspects of pipeline deterioration, the environmental activities that naturally clean hydrocarbon spills, and the difficulties of petroleum storage has started a new field, anaerobic hydrocarbon metabolism. Seen in the field as hydrocarbon splitting, this is a field with unprecedented possibilities.

This new science might need much more attention and funding for more research. The possibilities here stretch the imagination. What was once thought as depleted would not be, what was thought to be uneconomic may well be fruitful, what was once shut in might be a prolific production. There is lots of room for new careers in this area.

I look forward to more natural gas. It’s a common fuel, naturally made with a well known and in place distribution network already in place. If I were a politician, policy maker or investor, my prime concern wouldn’t be is the enough, but wondering when the next glut would be and the steps to help the business make and sell even more.

If energy security is the goal, then methane is the fastest and likely the lowest cost route to get there. With concentrated intelligence and effort, thoughtful and supportive policies, the U.S. can get to security and if truth be told – rather than be an energy importer, re-establish itself as an energy exporter once more.