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Can supercapacitors replace batteries?

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The electric car depends on batteries, and before EVs become a large chunk of our automotive fleet, there are probably going to be some changes.

Right now, Elon Musk is betting he can produce millions of small lithium-ion batteries not much bigger than the ones you put in your flashlight and string them together to power a $35,000 Tesla Model E over a range of 200 miles at speeds of up to 70-80 mph. The Model E also will also need an infrastructure of roadside “filling stations” and home chargers, although the best superchargers still take more than 20 minutes to achieve 80 percent capacity.

But there is another way to store electricity, long familiar to the designers of electrical circuits. It’s the capacitor, a device that stores a small current by static electricity rather than a chemical reaction. Capacitors sit in all of your electrical devices, from radio circuits to the most sophisticated laptops, and are essential to providing the steady electric current needed to run such electronics. But what if the concept of capacitors could be scaled up to the point where they could help power something as big as an electric vehicle? Granted, it’s a long, long way from the 1.5-volt capacitor in your iPad and powering a 4,500-pound Tesla along the Interstate, but researchers are out there probing and are already thinking in terms of a breakthrough.

Right now there’s a huge separation between the things that batteries can do and the things that capacitors can do. In a way they are complementary — the strengths of one are the weaknesses of the other. But researchers are working toward a convergence — or perhaps just a way of using them in tandem.

A battery employs chemistry by splitting ions in the electrolyte so that the negative ones gather on the cathode and the positive on the anode, building up a voltage potential. When they are connected externally an electric current flows. Batteries have a lot of energy density. They can store electricity up into the megawatt range and release a flow of electricity over long periods of time. The process can also be reversed, but, because the reaction is (once again) chemical, it can take a long time.

Capacitors store electrons as static electricity. A thundercloud is a great big capacitor with zillions of electrons clinging to the almost infinite surface area of individual raindrops. And as everyone knows, this huge stored capacity can be released in a “bolt of lightening.” Capacitors can be recharged almost instantly but also they release their energy almost instantly, rather than the even flow of a battery. One of their major uses is in flash photography. But their capacity for storing power is also limited. On a pound-for-pound basis, the best capacitors can only store one-fifth to one-tenth the equivalent of a chemical battery. On the other hand, batteries can start to wear out after five years, while supercapacitors last at least three times as long.

Back in the 1950s, engineers at General Electric, and later at Standard Oil, invented what have come to be called “supercapacitors.” Basically, a supercapacitor changes the surface material and adds another layer of insulating dielectric in order to increase storage capacity. Surface area is the key and engineers discovered that powdery, activated charcoal vastly increased the capacity of the storage plates. Dielectrics were also reduced to ultra-thin layers of carbon, paper or plastic, since the closer the plates can be brought together, the more intense the charge. Since then they have begun experimenting with graphene and other advanced materials that may be able to increase surface area by orders of magnitude. All of this means that much more electricity can be stored in a much smaller space.

But the problem of low energy density remains. Even supercapacitors can only operate at about 2.5 volts, which means they must be strung together in series in vast numbers in order to reach voltage levels required to power something like an electric car. This creates problems in maintaining voltage balance. Still, some supercapacitors are already being employed in gas-electric hybrids and electric buses in order to store the power siphoned off from braking.

Researchers in the field now see some possibility for convergence. Most exhilarating is the idea that the frame of the car itself could be transformed into a supercapacitor. Last month, researchers from Vanderbilt University published an online paper entitled, “A Multifunctional Load-Bearing Solid-State Supercapacitor,” in which they suggested that load-bearing materials such as the chassis of a car or even the walls of your house could be transformed into supercapacitors to store massive amounts of electricity on-site. Combined with advances in evening the flow of electrons from supercapacitors, this opens up whole new avenues of approach to the electric car.

All of these developments are a long way off, of course. Still, supercapacitors support the possibility of pulling out of your driveway in the morning and returning at night in your EV without needing to gas up with foreign oil at your nearest filling station.

Arctic Leaf

Shakespeare and Julia Child on monopolies, competition and alternative fuels

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You must remember the famous community activist who once asked, “To be, or not to be, that is the policy and behavior question; whether ‘tis nobler in the mind to suffer the slings and arrows of outrageously high, constantly shifting gasoline prices or to take arms against a sea of troubles generated by monopolistic fuel markets and open them up and end them.” I’m paraphrasing, of course.

Unfortunately, Shakespeare, now that we need him, is no longer available. But his question, articulated by his political friend Hamlet, still needs to be answered. I suggest we respond to his query in the context of another question: Is competition in the market for vehicular fuel a public good and in the public interest? Ah ha, you ask, why must we ask this question? Don’t we live in a capitalist or quasi-capitalist nation? Gosh, ever since we all were kids, were we not brought up on the wisdom of free markets and their ostensible link to freedom and democracy, a trifecta holy grail?

Sure we were! But the presented wisdom apparently didn’t mean all markets, and most important for this article, the market where most of us purchase fuel. By and large, the market for fuel is limited to a single, generally similar, primary product — gasoline. Competition, when it exists, generates from relatively small price differences, more often than not. Overblown value propositions in advertising concerning engine performance benefits from brand X or Y notwithstanding.

Consumers who, many times, assiduously read the papers or go online to find out where different brands of tires are cheapest or travel miles to visit dealers to get a perceived “good deal” on a car are frequently constrained to their neighborhood gas stations or the stations located near the nearest shopping center or big box store. While price may be a key factor in driving their decision as to which station will fill up their tank, absence of diverse fuel alternatives results in a relatively narrow band of prices per gallon and a competitive floor on consumer savings and costs.

Opening up gas markets will be tough. The oil industry controls or strongly influences over 40 percent of the stations and holds a big, profitable stick concerning what can be sold and how it can be sold at its franchised facilities. Prices are set low enough to scare independents into selecting less-than-favorable locations, or pricey enough to give them some room to keep their own costs relatively high.

To date, state pilot or demonstration programs concerning alternative fuels like ethanol and methanol have had mixed results. Why? Their costs of production and their environmental/GHG costs are lower than gasoline. Are we Americans just dumb? No. Initiatives to date have had to surmount problems including: consumer access to fuel stations with flex-fuel pumps (their costs range from $50,000 to over $100,000); a growing but still relatively small percentage of flex fuel autos compared to the total number of vehicles; the lack of consumer information concerning their own flex-fuel vehicle’s ability to use ethanol; the fear generated by some interest groups often related to the oil industry about the impact of alternative fuels on engines; the seeming ability of the oil industry to manage local prices; and the decisions by supply chain participants, particularly retailers to raise alternative fuel prices to capture immediate profits (reducing their intermediate and long-term ability — as the new kid on the block — to compete with gasoline.)

Evidence from Brazil suggests that demand emanating from an educated public, combined with a commitment to increase the pool of alternative-fuel vehicles and readily accessible fuel stations with ethanol pumps will cause a reduction in gasoline prices. Juliano J. Assunção, Joao Paulo Pessoa and Leonardo Rezende noted in a December 2013 London School of Economics publication, “Our estimates suggest that the model prediction is correct and that as the percentage of flex cars increase by 10%, ethanol and gasoline energy equivalent prices per liter fall by approximately 8 cents and 2 cents, respectively. Considering the volume of sales and size of the flex fuel fleet in 2007, a rough estimate suggests consumer savings to the order of 70 million Reais in the Rio de Janeiro state that year. Our estimates also show that the price gap as well as the price correlation between the two fuels has increased with the increased penetration of flex fuel cars.” Other studies have suggested similar positive impacts.

A U.S. recipe appears clear and consistent with America’s assumed belief in letting the market decide most resource allocation issues connected to the production of non-social welfare related goods and services. Ingredient one: Amend laws and regulations to encourage individual owners to convert older cars to flex-fuel automobiles; ingredient two: mix the resulting converted cars with newer flex-fuel vehicles to create a large flex-fuel pool; ingredient three: liberally sprinkle in enough information to inform consumers and potential-ethanol-supply-chain participants, including potential blenders and retailers, of the potential demand for ethanol as a fuel; ingredient four: add real, solid seasoning to the mix by fostering development, distribution and the sale of natural-gas-based ethanol to achieve significant increased environmental and cost benefits. Julia Child couldn’t build a better dish for the nation as it simultaneously tries to expand the viability of renewable fuels, and Shakespeare’s friend, Hamlet, would not need antidepressants.

Arctic Leaf

DME poses a challenge to CNG

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If there’s an Achilles’ heel to the efforts being made to introduce compressed natural gas (CNG) into the country’s vehicles, it is that somebody is going to come along with a liquid fuel that works much better.

CNG has many things going for it. Natural gas is now abundant and promises to stay that way for a long time. That puts the price around $2 a gallon, which is a big savings when gas costs $3.50 and diesel costs $3.70 per gallon. Trucks — mid-sized delivery trucks and big 18-wheelers — are the target market. Delivery vans usually operate out of fleet centers where a central compressor can be installed to service many vehicles. Meanwhile, pioneering companies such as Clean Energy Fuels are busy building an infrastructure at truck stops along the Interstate Highway System to service long-hauling tractor-trailers on their cross-country routes.

But there is a weakness. As a gas, CNG requires a whole new infrastructure. Compression tanks must be built at gas stations, much stronger than ordinary gas tanks and tightly machined, so gas does not escape. Even under compression, CNG has a much lower energy density than gasoline. This requires special $6,000 tanks that must still take up more space. In passenger vehicles they will devour almost all the trunk space, which is why vendors are concentrating on long-distance tractor-trailers.

As a result, there always seems the chance that some liquid derivative of methane is going to come along and push CNG off the market. Methanol has been a prime candidate since it is already manufactured in commercial quantities for industrial purposes. M85, a mixture of 85 percent methanol and 15 percent gasoline, is legal in the United States, but has not been widely adopted.

Now a new candidate has emerged in the long-distance truck competition — dimethyl ether or “DME.” Two methane ions joined by a single oxygen molecule, DME is manufactured from natural gas and has many of the same properties as methanol. It is still a gas at room temperature but can be stored as a liquid at four atmospheres or -11o F. It can also be dissolved as a gasoline or propane additive at a 30-70 percent ratio. In 2009 a team of university students from Denmark won the Shell Eco Marathon with a vehicle running on 100 percent DME.

So is it practical? Well, we’ll soon find out. Volvo has just announced it will release a version of its D13 truck in 2014 that runs on DME. At the same time, Volvo pushed back the launch of its natural gas version of the same line, meaning it may be changing its mind about which way the technology is going to go. In case you haven’t been keeping abreast, Volvo is now the largest manufacturer of heavy trucks in the world, having acquired Mack, America’s oldest truck company, in 2000.

So does that mean that CNG may turn out to be a dead end and Clean Energy Fuels is going to get stuck with a lot of unused compressor pumps? Well, hold on a minute. Technology does not stand still.

Last week at the Alternative Clean Transportation Expo in Long Beach, Calif., Ford and BASF unveiled a new device for the Ford F-450 CNG fuel tank. It’s called a Metal Organic Framework (MOF), a complex of clustered metal ions built on a backbone of] rigid organic molecules that form one-, two-, or three-dimensional structures. Lots of surface area is created, making MOFs porous enough to hold large amounts of gaseous material such as methane.

MOFs create the possibility that on-board CNG tanks will not have to operate under extremely high pressure or extremely low temperatures. Like a metallic sponge the high-surface material soaks gas right up, where it can be easily dislodged as well. According to BASF and Ford, the same amount of natural gas that requires 3,600 pounds per square inch (PSI) can be stored in an MOF tank at close to 1,000 PSI. That makes a big difference when it comes to designing an automobile.

So does that mean natural gas is going to be able to hold its own against DME and other liquid competitors? Well, wait a minute, there’s still more. Not only is MOF technology good at storing methane, it also works with hydrogen! That means the hydrogen-fuel cell — still the favorite among Japanese manufacturers — may be able to work its way back in the game as well.

In fact, Ford isn’t playing any favorites. Equipped with its new MOF tanks, the F-450 will offer drivers a choice of seven — that’s right, seven — different fuel options using the same internal combustion engine. “Ford has no idea which of these fuels will make the most sense,” Ford’s Jon Coleman told Jason Hall of Motley Fool. “So we need to build vehicles that have the broadest capability and the broadest fuel types so our customers can choose for themselves.”

That’s the name of the game. It’s called Fuel Freedom.

Arctic Leaf

Star light, star bright: Wishing for a cleaner, less-expensive fuel

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Star light, star bright, I wish I may, I wish I might, have this wish I wish tonight… How many of you said these words on a starry night, particularly if you were with your best girl or boyfriend as a teenager? Or, as a loving parent, how many of you taught your child to say these words as part of your effort to build his or her vocabulary or memory…or just to instill their capacity to dream?

Now Kate Gordon, the, legitimately well respected, president of Next Generation, seems to have forgotten the difference between wishing, hoping, dreaming and reality. Her recent brief “expert” article in the Wall Street Journal departs from reasonable projection into fanciful wishes.

Gordon is correct that the “average car” on the U.S. road is about 11 years old and that their negative impact on GHG emissions and our health is significant. She is also correct in pointing to the large impact that high gas prices have on “our wallets,” (I would add) particularly for low and moderate-income households. Clearly, for the poor and near-poor families and for the economically fragile moderate-income households, present gas prices mean less of the basic necessities: modest job choices, good food, housing and healthcare.

Where Gordon and I part company is with her suggestion that an auto replacement initiative or what she calls an Enhanced Fleet Modernization programs would generate a visible, short-term impact and would likely be supported now, by assumedly the federal or state governments, in a significant way. (I should indicate that while I was head of the urban policy in the Carter administration, HUD senior officials thought about offering support by providing older cars to carless, low-income folks to permit them to secure job opportunities in the suburbs. How times have changed. The concern about GHG emissions and other pollutants emitted from older cars that run on gasoline are now seen as a real environmental problem.) The difficulty with Ms. Gordon’s proposal is number one, money and bureaucracy; number two, money and bureaucracy; and number three, money and bureaucracy. Even California, which she touts, has had mixed results with its replacement and incentives to replace older car programs. Clearly, exporting California’s experience to many other states, given economic and political constraints, would be difficult and would likely result annually in a relatively small impact on the nearly 300,000,000 cars in the U.S of which approximately 85-90 percent are over six years old.

Car replacement is a nice thought, but probably, at this time, an exotic one. If policymakers are seriously looking for a way for large numbers of owners of older cars to immediately reduce their vehicle’s negative effect on the environment, air quality and their own costs of fuel, there are better ways. While we wait and hope for the advent of vehicles that are ready to run on renewable fuels and that simultaneously meet the travel as well as budget needs and demands of most low, moderate and middle-income Americans, we should look at natural-gas-based ethanol as a fuel for newer flex fuel cars and for large numbers of older vehicles converted to flex-fuel vehicles.

Ethanol is not perfect as a fuel but it is better than gasoline. It emits fewer GHG emissions and other pollutants harmful to the nation’s quality of life. Recent regulations, like ones initiated by Colorado, that significantly reduce emissions from drilling now will likely make life cycle environmental evaluations of natural gas changed into ethanol a much better environmental deal. The process appears technologically feasible at a cost lower than the production costs of gasoline. If ethanol is allowed to compete with gasoline by oil companies on an even playing field — oil companies generally control who gets what and where at most “gas” stations — ethanol will be cheaper than gasoline for the consumer.

It is relatively inexpensive to convert older cars to flex-fuel vehicles — perhaps as little as $100 to $200. Finding a way through lessening the cost of certification to expand the number of conversion kits certified by the EPA and, or, where relevant, allowing recalibration of software and engines, would expand the benefit-cost ratio for many older cars. Star light, star bright, we can have the wish we wish tonight concerning a cleaner environment and lower consumer prices in a relatively short time, while we continue to push for electric vehicles and a whole range of renewable fuels to achieve prime-time performance for most Americans.

Arctic Leaf

Clean Energy Fuels sees daylight ahead

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Wall Street was abuzz last week as Clean Energy Fuels, the leading supplier of natural gas for use in delivery and heavy-duty trucks, jumped 11 percent in one day after a long slump in which investors were questioning its business model.

“We’re at the very beginning of a major shift to natural gas for trucking – a shift that could take a decade before the growth slows – and Clean Energy Fuels is the leader in the market,” added Jason Hall of Motley Fool, who had been skeptical of the company in the past but is now turning enthusiastic.

“Natural gas vehicles are here to stay,” added James E. Brumley on SmallCap Network, in one of the many enthusiastic endorsements the company received last week. “So Clean Energy Fuels is very much a right-time, right-place idea. It’s not just that the company is the biggest and the best at what it does. There’s a market of scale for what it has to offer.”

It hasn’t been easy. The company, the brainchild of legendary oilman T. Boone Pickens, seemed poised for growth last year but suddenly hit a sudden downdraft in January. Skepticism grew over whether compressed natural gas (CNG) or liquid natural gas (LNG) would be the best substitute for diesel in heavy-duty trucks. The debate is really inconsequential since the two are interchangeable – LNG for large-scale storage and transport with some use in the biggest rigs and CNG for fueling smaller commercial vehicles. Nevertheless, the controversy drove down CEF’s stock price 25 percent since the first of the year.

“Much of the conversation in the investor community over the past six months has been dominated by the false idea that CNG and LNG were competing fuels,” wrote Hall in a recent evaluation. “But while we’ve been arguing, Clean Energy Fuels has been opening stations for trucks across the country. And the company is a leader in both.”

Once again, it seems to have been a case of investors becoming absorbed in short-term focus while ignoring the long-term prospects of the company. True, Clean Energy Fuels has not yet delivered a profit but its progress in building infrastructure to enable us to use significant portions of our natural gas resources as a substitute for diesel fuel has been significant. Here’s what the company has accomplished so far:

  • Clean Energy Fuels has delivered 800 million gallons of CNG and LNG to light and heavy-duty trucks.
  • The company has built approximately 500 fueling stations across the country.
  • It has installed over 1,500 compressors for delivering CNG to vehicles worldwide.
  • It has two LNG production plants.
  • It has 60 LNG tankers making 5,000 deliveries every year.
  • It has two renewable natural gas plants producing bio-methane.
  • It has 39 major airport fueling stations.
  • It now fuels over 35,000 trucks, large and small, with CNG each day.

As you can see, this is no fly-by-night operation. Whether the company is profitable or not right now, Pickens is obviously in it for the long haul.

Clean Energy Fuels’ long-term goal is a “CNG superhighway” that will offer fueling stations to long-haul trucks along all the major interstates that crisscross the country. But its major success to date has been in servicing fleet vehicles for delivery companies and municipalities.

  • CEF currently services 230 trucks a day for UPS with big plans for expansion.
  • CEF has contracts with Owens-Corning, Lowe’s, Proctor & Gamble and other commercial establishments’ fleet owners for their delivery vehicles.
  • Garden City Sanitation of San Jose has converted 23 refuse trucks to natural gas using CEF’s services.
  • CEF will be fueling Kroger’s new 40-unit fleet of LNG trucks later this year.

Analysts believe that refuse and delivery fleets, especially those that are garaged overnight and can be refueled at a central CNG station, will become one of the company’s major markets.

CEO Andrew Littlefield just announced a loss in revenues for the first quarter of 2014 but said this was because of the expiration of the federal volumetric excise tax credit (VETC), which had provided $26 million in 2013. Overall, the trend is definitely upward:

  • LNG fuel deliveries increased 22 percent to 16.7 million gasoline gallon equivalents.
  • CNG deliveries increased 16 percent.
  • When the VETC is excluded, overall revenues were up 43 percent. 
  • Sales of Redeem, the company’s renewable bio-methane product, increased 45 percent.

Sean Turner, COO for Gladstein, Neandross & Assoc., a leading consulting firm for the development of alternative fuels, notes that the NGV market in the United States is actually larger than in countries such as Argentina and Pakistan, which have been at it for a longer time. “While North America might lag behind in the adoption curve of other countries, natural gas usage per vehicle is actually near the top worldwide,” he said. “This is because other countries have tended to employ NGVs for passenger cars, whereas the U.S is now concentrating on medium-sized and heavy-duty trucks.” And as T. Boone Pickens likes to point out, natural gas will be unrivaled in this marketplace since electric vehicles cannot produce the torque needed to power those long-haul vehicles.

Whether all this makes Clean Energy Fuels a hot stock again is something Wall Street will have to decide. But in terms of moving America toward greater reliance on homegrown natural gas, the news is all favorable.

Arctic Leaf

Let freedom ring: Oil companies, capitalism and fuel choice

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It’s a free county, ain’t it? Americans have many choices that are denied to citizens of other less-fortunate nations. But we forget how many decisions are made for us, sometimes out of necessity, such as paying taxes; sometimes out of greed, such as the monopolistic actions of oil companies in denying many Americans the ability to purchase alcohol-based fuels at their corner gas station. Try it someday! On your way home from work, on your shopping trip to your friendly supermarket or on your way to see a movie at your favorite theater, make a stop for fuel at a gas station. Make sure to have some gasoline in your tank, because it likely will take you a lot of time to find a gas station that sells E85 or even E15.

Now, I went to Harvard Law School for four days, before I decided that there were too many lawyers around and memorizing case studies was not my forte. But Harvard provides significant value added, apart from being near Harvard Square and Boston. I was exposed to terms and content related to antitrust, restraint of trade, collusion and monopolies. Now, I didn’t stay long enough to know whether those concepts applied to oil companies that restrict consumer choices of alternative fuel. Probably not, because I am sure, by now, one of my Harvard colleagues would have filed a well-reimbursed case to break open the fuel market to options like ethanol, methanol and more. But whether legal or not, oil companies deserve their comeuppance for limiting many of us who, too often, are required to use more expensive, environmentally harmful gasoline, instead of existing, safe, alternative fuels.

How do they do this? Well, if you are a gas station owned or franchised by an oil company, your contract and rules related to behavior often prevent you from adding a pump or adding to an existing pump to sell E15 or E85. As relevant, since oil companies generally require the stations they own to buy fuel from them, and since they don’t sell E15 or E85, adding a pump would be akin to waiting for the hereafter (and acting on faith that you will get there).

Wait, there is more! Every now and then an oil company wants to publicly show it is a bit beneficent (for image purposes), but don’t hold your breath with respect to proof that image and reality are the same. Sure, you might find an alternative-fuel pump near the rear side of the garage proximate to the men’s room, or, if you are lucky, on the side of the station near the air pump. Most oil-company-owned stations and franchisees are generally precluded from putting an alternative-fuel pump under the covered island or space out front. They also face restrictions on advertising alternative fuels as an available product and oil-company pricing limits competition from alternative fuels.

Congress has refused to enact open fuels legislation, which would require oil companies to open up their gas stations to other fuels. Ongoing efforts by public and private sector advocates, as well as nonprofit groups, to encourage policies that would convert older cars to flex-fuel vehicles and to encourage Detroit to build more FFVs could well lead to a large consumer market for alternative fuels and generate a positive market reaction among independent gas companies and, perhaps, even some smart oil companies. While I have been wading through the pros and cons of allowing oil companies to increase exports to other nations, I do believe that if increased exports are in the nation’s future, they should be approved only if the oil companies agree to require their stations and franchises to offer alternative fuels in a primary space alongside gasoline. A bit of tat for tat is in the public interest. Let freedom ring for consumer! Let capitalism mean competition for gasoline and alternative fuels at your nearby gas station! Oh, I forgot, alternative fuel station!

Arctic Leaf

From lab to market, it’s a long haul

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The Energy Information Administration has done us an enormous favor by producing a simple chart to make sense of where the development of energy storage technology is going. Energy storage, as the EIA defines it, includes heat storage, and a quick look at the chart reveals that those forms that involve sheer physical mechanisms – pumped storage, compressed air and heat reservoirs – are much further along than chemical means of storage, particularly batteries.

The EIA divides the development of technologies into three phases – “research and development,” “demonstration and deployment” and “commercialization.” It also ranks them according to a factor that might be called “chances for success,” which is calculated by a multiple of capital requirements times “technological risk.”

As it turns out, only two technologies that could contribute to transportation are in the deployment stage while three more are in early development. The two frontrunners are sodium-sulfur and lithium-based batteries while the three in early stages are flow batteries, supercapacitors and hydrogen. The EIA refers to hydrogen as one of the ways of storing other forms of energy generation, particularly wind and solar. But hydrogen is also being deployed in hydrogen in hydrogen-fuel-cell vehicles that have already been commercialized.

Other than building huge pumped-storage reservoirs or storing compressed air in underground caverns, the chemistry of batteries is the most attractive means of storing electricity, which is the most useful form of energy. Batteries have always had three basic components, the anode, which stores the positive charge, the cathode, which stores the negative charge, and the electrolyte, which carries the charge between them. Alexander Volta designed the first “Voltaic pile” in 1800 by submerging zinc and silver in brine. Since then, battery improvements have involved finding better materials for all three components.

Lead-acid batteries have become the elements of choice in conventional batteries because the elements are cheap and plentiful. But lead is one of the heaviest common elements and becomes impractical when it comes to loading them aboard a vehicle.

The great advantage of lithium-ion batteries has been their light weight. The lithium substitutes for metal in both anode and cathode, mixing with carbon and iron phosphate to create the two charges. Li-ion, of course, is the basis of nearly all consumer electronics and has proved light and powerful enough to power golf carts. The question being posed by Elon Musk is whether they can be ramped up to power a Tesla Model S that can do zero-to-60 with a range of 300 miles.

Tesla is not planning any technological breakthrough, but will use brute force to try to scale up. Enlarging li-ion batteries tends to shorten their life so the Tesla will pack together thousands of small ones no bigger than a AA that will be linked by a management system that coordinates their charge and discharge. Musk is betting that economies of scale at his “Gigafactory” will lower costs so that the Model X can sell for $35,000. According to current plants, the Gigafactory will be producing more lithium-ion batteries than are now produced in the entire world.

In the sodium-sulfur battery, molten sodium serves as the anode while liquid sodium serves as the cathode. An aluminum membrane serves as the electrolyte. This creates a very high energy density and high discharge rate of about 90 percent. The problem is that the battery must be kept at a very high temperature, around 300 degrees Celsius, in order to liquefy its contents. A sodium-sulfur battery was tried in the Ford “Ecostar” demonstration vehicle as far back as 1991, but it proved too difficult to maintain the temperature.

Flow batteries represent a new approach where both the anode and cathode are liquids instead of solids. Recharging takes place by replacing the electrolyte. In this way, flow batteries are often compared to fuel cells, where a steady flow of hydrogen or methane is used to generate a current. The great advantage of flow batteries is that they can be recharged quickly by replacing the electrolyte, rather than taking up to 10 hours to recharge, as with, say, the Chevy Volt. So far flow batteries have relatively low energy density, however, and their use may be limited to stationary sources. A German-made vanadium-flow battery called CellCube was just installed by Con Edison as a grid-enhancement feature in New York City this month.

Supercapacitors use various materials to expand on the storage capacity devices in ordinary electric circuits. They have much shorter charge-and-discharge cycles but only achieve one-tenth of the energy density of conventional batteries. As a result, they cannot yet power vehicles on a stand-alone basis. However, supercapacitors are being used to capture braking energy in electric trams in Europe, in forklifts and hybrid automobiles. The Mazda6 has a supercapacitor that uses braking energy to reduce fuel consumption by 10 percent.

The concept of “storage” can be also be expanded to include hydrogen, since free hydrogen is not a naturally occurring element but can store energy from other sources such as wind and solar. That has always been the dream of renewable energy enthusiasts. The Japanese and Europeans are actually betting that hydrogen will prove to be a better alternative than the electric car. Despite the success of the Prius hybrid, Toyota, Honda and Hyundai (which is Korean) are putting more emphasis on their fuel cell models.

Finally, methanol can be regarded as an “energy storage” mechanism, since it too is not a naturally occurring resource but is a way to transmit the potential of our vast reserves of natural gas. Methanol proved itself as a gasoline substitute in an extensive experiment in California in the 1990s and currently powers a million cars in China. But it has not yet achieved the recognition of EVs and hydrogen – or even compressed natural gas – and still faces regulatory hurdles.

All these technologies offer the potential of severely reducing our dependence on foreign oil. All are making technical advances and all have promise. Let the competition begin.

Arctic Leaf

Can graphene, the wonder material, build better batteries?

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In 1962, German researcher Hanns-Peter Boehm suggested the versatile carbon atom, which can form long chains, might be configured into a chicken-wire pattern to create a stable molecule one atom thick.

The idea remained a theoretical construct without even a name until 1987, when researchers started calling it “graphene.” Basically, graphene is two-dimensional graphite, the pure carbon material that makes up “lead” pencils. The term was also used to describe the carbon nanotubes that were beginning to attract attention for their ultra-solid properties. For a while there was talk of elevators reaching up into space until it became clear that creating nanotubes without impurities that degrade their properties was currently out of the reach of mass production.

Then in 2004, Andre Geim and Kostya Novoselov, two researchers at The University of Manchester, came up with something a little more prosaic. They applied Scotch tape – yes, ordinary Scotch tape – to pure graphite and found they could peel off the single layer of carbon in the chicken-wire pattern that Boehm had described. They called this substance “graphene” and were awarded the Nobel Prize in 2010.

The discovery of single-layer graphene has set off a stampede into research of its properties. Carbon is, after all, a versatile element, the basic building block of life that can also be packed into a material as hard as a diamond, which is also pure carbon. When stretched out into lattices a million times thinner than a human hair, however, it has the following remarkable properties:

  • It is the strongest material ever discovered, 300 times stronger than steel.
  • It is the most electrically conductive material ever discovered, 1,000 times more conductive than silicon.
  • It is the most thermally conductive material ever discovered.
  • It is bendable, shapeable and foldable.
  • It is completely transparent, although it does filter some light.

In short, graphene is now being touted as “material of the 21st century,” the substance that could bring us into an entirely new world of consumer products, such as cell phones that could be sewn into our clothes.

All this still remained somewhat theoretical, since no one had been able to produce graphene in dimensions larger than single tiny crystals. When these crystals were joined together, they lost most of their properties. Two weeks ago, however, Samsung announced that it has been able to grow a graphene crystal to the size of a wafer, somewhat on the same dimensions as the silicon wafers that produce computer chips. Thus, the first step toward a new world of electronics may be upon us. Graphene cannot be used as a semiconductor, since it is always “on” in conducing electricity, but combined with other substances it may be able to replace silicon, which is many researches believe is currently reaching its physical limits.

So what does this mean for the world of transportation, where we are always looking for new ways to construct automobiles and find alternative power sources to substitute for our gas tanks? Well, plenty.

Most obvious is the possibility of making cars out of much lighter-weight materials to reduce the power burden on engines. Chinese researchers recently came up with a graphene aerogel that is seven times lighter than air. A layer spread across 28 football fields would weigh only one ounce and a cubic inch of the material would balance on a blade of grass. All this would occur while it still retained its 300-times-stronger-than-steel properties. Graphene itself would not be used to construct cars, but it could be layered with other materials.

But the most promising aspect of graphene may be in the improvement of batteries. Lithium-ion batteries achieve an energy density of 200 Watt-hours-per-kilogram, which is five times the 40-Wh/k density of traditionally lead-acid batteries. That has won it the prime role in consumer electronics. But Li-ion batteries degrade over time, which is not a problem for a cell phone, but becomes prohibitive when the battery must undergo more than 1,000 charge cycles and is half the price of the car.

Lithium-sulfur batteries have long been thought to hold promise but they, too, deteriorate quickly, sometimes after only a few dozen charges. But recently, researchers at Lawrence Berkeley Labs in California modified a lithium sulfur battery by adding sandwiched layers of a graphene. The result is a battery that achieves 400 Wh/k – double the density of plain lithium-ion – and has gone through 1,500 charging cycles without deterioration. This would give an electric car a range of more than 300 miles, which is in the lower range of what can be achieved with the internal combustion engine.

And so the effort to improve electric vehicles is moving forward, sometimes on things coming out of left field. If graphene really proves to be a miracle substance, look for Elon Musk to be discussing its wonders as he prepares to build that “megafactory” that is supposed to produce lithium-ion batteries capable of powering an affordable new version of the Tesla.

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Is butanol the next big thing in biofuels?

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Fuel Freedom recently learned about a man named David Ramey who drove his 1992 Buick Park Avenue from Blacklick, Ohio to San Diego using 100 percent butanol, without making any adjustments to his engine.

Ordinarily this wouldn’t be big news. But with the EPA now considering cutbacks in the 2014 biofuels mandate, some producers of ethanol are starting to turn to butanol as a way of getting around the limitations of the 10 percent “blend wall” that is threatening to limit ethanol consumption. This could be another breakthrough in our efforts to limit foreign oil.

Butanol is the alcohol form of butane gas, which has four carbons. Because it has a longer hydrocarbon chain, butane is fairly non-polar and more similar to gasoline than either methanol or ethanol. The fuel has been demonstrated to work in gasoline engines without any modification to the fuel chain or software.

Since the 1950s, most butanol in the United States has been manufactured from fossil fuels. But butanol can also be produced by fermentation, and that’s where another opportunity for reducing our dependence on fossil fuels exists.

The key is a bacterial strain called Clostridium acetobutylicum, also named the Weizmann organism for pioneering biological researcher Chaim Weizmann, who first used it to produce acetone from starch in 1916. The main use for the acetone was producing Cordite for gunpowder, but the butanol, a byproduct, eventually became more important.

Once set loose on almost any substratum, Clostridium acetobutylicum will produce significant amounts of butanol. Anything used to produce ethanol — sugar beets, sugar cane, corn grain, wheat and cassava, plus non-food crops such as switchgrass and guayule and even agricultural byproducts such as bagasse, straw and corn stalks — can all be turned into butanol. (Of course, not all of these are economical yet.)

Given the modern-day techniques of genetic engineering, researchers are now hard at work trying to improve the biological process. In 2011, scientists at Tulane University announced they had discovered a new strain of Clostridium that can convert almost any form of cellulose into butanol and is the only known bacterium that can do it in the presence of oxygen. They discovered this new bacterium in, of all places, the fecal matter of the plains zebra in the New Orleans Zoo.

DuPont and BP are planning to make butanol the first product of their joint effort to develop next-generation biofuels. In Europe, the Swiss company Butalco is developing genetically modified yeasts from the production of biobutanol from cellulosic material. Gourmet Butanol, a U.S. company, is developing a process that utilizes fungi for the same purpose. Almost every month, plans for a new butanol production plant are announced somewhere in the world. Many refineries that formerly produced bioethanol are now being retrofitted to produce biobutanol instead. DuPont says the conversion is very easy.

What are the possible drawbacks? Well, to match the combustion characteristics of gasoline, butanol will require slight fuel-flow increases, although not as great as those required for ethanol and methanol. Butanol also may not be compatible with some fuel system components. It can also create slight gas-gauge misreadings.

While ethanol and methanol have lower energy density than butanol, both have a higher octane rating. This means butanol would not be able to function as an octane-boosting additive, as ethanol and methanol are now doing. There have been proposals; however, the proposals are for a fuel that is 85 percent ethanol and 15 percent butanol (E85B), which eliminate the fossil fuels from ethanol mixes altogether.

The only other objection that has been raised is that consumers may object to butanol’s banana-like smell. Other than that, the only problem is cost. Production of butanol from a given substratum of organic material is slightly lower than ethanol, although the increased energy content more than makes up for the difference.

Ironically, the EPA’s decision to cut back on the biofuels mandate for 2014 is now driving some refiners to convert to butanol, since its greater energy density will help it overcome the 10 percent “blend wall.”

“Michael McAdams, president of the Advanced Biofuels Association, an industry group, said butanol was a ‘drop-in’ fuel, able to be used with existing gasoline pipelines and other equipment because it does not have a tendency to take up water, as ethanol does,” The New York Times reported last October. “‘It’s more fungible in the existing infrastructure,’ he said. ‘You could blend it with gasoline and put it in a pipeline — no problem.’

“Butanol would also help producers get around the so-called blend wall, Mr. McAdams said…With the 10 percent limitation, ‘you don’t have enough gasoline to put the ethanol in,’ he said. ‘You don’t have that problem with butanol.’”

So here’s to butanol. It will be yet another big step in reducing our dependence in foreign fuels.

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Take me shopping for eggs, copper and corn starch

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Good news for a world often filled with bad news has recently been generated by two major U.S. universities, both in regards to the efficacy of alternative fuels. Maybe the announcements will lend confidence that America can find a way to balance economic growth with environmental concerns. Increasing success over time will mean that (paraphrasing in part, the late Sen. Robert Kennedy) the nation will not have to accept “what is” with respect to the dominance of gasoline as a fuel, but can consider “what could be” concerning the use of alternative, cleaner, safer, environmental-better and cheaper fuels.

Stanford University professors, in a paper co-authored by Dr. Matthew Kanan, assistant professor of chemistry, announced that they have developed a copper catalyst that can efficiently convert carbon monoxide and water into ethanol. Quoting from a recent MIT Technology Review (April 2014), “while the work is still experimental, it’s significant because the group was able to synthesize ethanol and other desired products with so little energy input.” The Stanford researchers envision a “two-step process in which carbon dioxide is first converted into carbon monoxide using either existing processes or more energy-efficient ones that are currently under development. Then, the carbon monoxide would be converted to ethanol or other carbon-based compounds electrochemically. The key to the new catalyst is preparing the copper in a novel way that changes its molecular structure.”

How long will it take to get from idea to market? If the copper-based process survives further lab tests and evaluations, and if it is then converted into a prototype that is able to produce ethanol fuel, a big push to convert the prototype to real-world status from both the private sector and government would be warranted.

Stanford’s “breakthrough” — if the process becomes marketable and can generate lower-priced, environmentally-safe ethanol that is capable of fueling flex-fuel vehicles (FFVs) and older, converted FFVs — will be significant, even perhaps a disruptive technology. With the proper support, hopefully in the not-too-distant future, increased use of the copper catalyst will minimize and maybe even end the food vs. fuel and land-use allocation fights, as well as help resolve GHG emissions and other pollutant issues that have sometimes frustrated the use of corn-based ethanol and muted receptivity to natural-gas-based ethanol. Technological improvements concerning production reflected in recent life-cycle analysis of corn-based ethanol and reasonable assumptions concerning the cost and environmental benefits of natural-gas-based ethanol, combined with the success of Stanford’s copper catalyst approach, could offer owners of FFVs (both converted and new vehicles) a wider variety of alternatives to secure ethanol that, clearly, will be cheaper, safer and better for the environment.

Stanford’s good news was matched by Cornell’s. Dr. Yingchao You and Dr. Hao Chen announced that they had discovered that a component of corn starch and the yolk shell structure of eggs improve the durability and performance of lithium batteries. In this context, they note that lithium-sulfur batteries are a very solid alternative to lithium-ion batteries. Stabilization problems related to its capacity can be resolved by using amylopectin, a polysaccharide (mainly good old corn starch).

Enveloping the battery’s lithium sulfur cathodes, with an encasing resembling the shell of an egg yolk (sulfur coated with an inexpensive polymer) also apparently improves the battery’s durability and performance.

Cornell has initiated a startup company to take the new and improved starch, egg-yolk shell battery to market. Maybe sometime soon, moderate and middle-income owners of electric cars that are less expensive than what is now available will be able to reduce their fear of driving long distances and feel confident about the life and efficiency of the batteries in their vehicles.

I avoided chemistry, physics and engineering in college. I knew I was not destined to become neither city planner nor designer at MIT when my first student-planned bridge went under water instead of over it. While my efforts were applauded by the Malthusians among my colleagues, they were not regarded highly by professors. Since graduation, unless supported by respected colleagues with a background in relevant sciences and engineering, I have been hesitant to suggest approval of science-driven energy innovations. I am a policy and program person. However, after review and discussions with trusted experts, I believe the Stanford and Cornell initiatives have a good chance to see the light of day, or, more appropriate, see the light in the market place. If one or both do, we will all be better off and the number of feasible alternative transportation fuels available to the consumer will grow. Hooray for copper, starch and eggs.