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Is the Answer Encapsulated Hydrogen?

 

Here’s the problem: gasoline is an incredibly efficient energy-storage medium that’s hard to beat with current technology. A gallon of gasoline packs 114,000 BTU, which is the caloric equivalent of  about 43,000 Whoppers (without cheese, but with mayonnaise). This means the gas tank of a KLR650 contains enough energy to provide a nice lunch to a small city. That’s enough energy-storage capacity to ignore the inefficiencies of internal-combustion engines and drivetrains, where typically less than 20 percent of those burgers actually turn the back tire. 

Electric-powered vehicles are much more efficient—somewhere in the 75 to 85 percent range, in fact. But the pathetic energy density of current battery technology is the weak point, even though huge strides have been made in the last decade. Still, judging from the feedback to our story on the new Zero motorcycles, a motorcycle with a 40-mile range (and a top speed of less than 70 mph) isn’t going to impress anyone. Even if that capability doubles in 10 years, it’s still not that appealing to those of us used to cruising at  80 mph and going 150 miles or more between our 5-minute fill-ups. 

Hydrogen offers a solution. It’s the most abundant material in the universe, has three times the energy density of gasoline, and the most harmful pollutant emitted when it’s burned is steam (yes, I know it takes more energy to generate hydrogen than it stores). It can also power fuel cells to generate electricity, a proven (if expensive) technology that’s been in use for 50 years. The problem is that hydrogen is explosive (how was that trip to Lakehurst, Herr Zeppelin?) and must be stored and transported either at very high pressures or very low temperatures. That’s expensive to do, which means that hydrogen—in its current form—is a long way from being a practical fuel. 

But what if you could somehow pack that hydrogen into a substance that could be stored and transported like regular unleaded? That’s exactly what U.K.-based Cella Energy says its new technology will allow. Through a new process called “coaxial electrospinning,” chemical hydrides (hydrogen-containing compounds) are trapped in a nano-porus polymer. No, I don’t have any idea what that means, either, except that the end result is micron-sized beads that can store hydrogen. Since the beads are so tiny (if you laid a million end to end they would stretch a bit over three feet) a large quantity has properties similar to water. 

These beads could be stored in a plastic fuel tank in a vehicle, and then pumped into a “hot cell” where the hydrogen would then be used in a fuel cell, or in an internal-combustion engine. The empty nano-beads could then be stored in another tank for future disposal. The encapsulated hydrogen could also be somehow mixed with hydrocarbon fuel to boost its energy level and lower emissions. 

Sound too good to be true? Well, actually, it is—at least for now. The ammonia-borane/polystyrene nano-scaffold Cella has been using to develop encapsulated hydrogen is “not currently a viable commercial material: it is expensive to make and cannot be easily re-hydrided or chemically recycled.” 

But that doesn’t mean it won’t happen soon. “Better living through chemistry” is a cliché, but our modern civilization wouldn’t be remotely possible without the huge advances in chemical engineering we’ve seen in the last 150 years, advances that would seem like magic to a person from the 18th century. Will nanotechnology let us enjoy clean-burning, high-performing motorcycles guilt free? Or will we be stuck with the inoffensive hum of electric motors?

86 Comments

  1. Random says:

    Thankfully where I live petroleum-based energy sources for transportation are being systematically changed to ethanol or bio-diesel ones. Not really zero emissions but I believe at least some of that CO2 is going back to all that sugarcane (just to be burned again later).

    The better part of it is that it works, burns, vibrates and sounds just like any conventional engine you had before – even if it smells a little funny.

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  2. Zuki says:

    We are supplicants for knowledge! All hail to the greatest internet minds of the 21st century! Do not form an opinion and foolishly write it down here without approval. Be prepared to receive a wrathful gift for your weak mind… a convoluted educational spill, complete with “maximum confusion effect” from Tom Barber, or the preaching word of kpaul, the modern day Nostradamus!

    Both have knowledge that is beyond reproach (omnipotent, and/or sourced from government websites and Wikipedia.org). You shall accept and do what they say as absolute fact or be damned for the rest of your internal combustion polluting days!

    Of course, you may repent and never again describe engine torque (or anything physics or science-related)incorrectly or buy a ‘Zero’ bike or other electric vehicle today! Do so, and you may find rapture awaits you!

    Stop pretending to be an engineer or scientist! Stop your disgusting, filthy habit of burning gasoline!!

    Beware. Don’t forget to kneel. Bow your heads. Accept. Be saved. Join Us.

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  3. Tom K. says:

    Not to pick nits, but there are closer to 43 Whoppers of equivalent energy in a gallon of gasoline than 43,000. Assuming 670 FOOD calories in a Whopper, and 252 HEAT calories per btu, and using your 114,000 btu’s per gallon of gas, the result is 42.9 Whoppers. I think your error came from assuming that a food calorie is the same as a heat calorie, when in reality, one food calorie contains the energy of 1000 heat calories. Either way, drink a gallon of gas or eat 43 Whoppers, same result. I’ll be quiet now….

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    • Tom Barber says:

      This is correct. The stated quantity in BTU translates to 2.87×10^7 regular (small) calories. A Burger King Whopper has 670 food (large) calories, which is equivalent to 6.7×10^5 regular (small) calories. The ratio is roughly 43.

      I would not have believed that 43 Whoppers contain as much energy as a gallon of gasoline. But I was also confused at first because I was thinking of the other kind of Whopper, you know, the chocolate-covered malted milk kind that Hershey makes. Each individual Whopper (small) contains 10.6 calories (large). Thus, roughly 63.4 Whoppers (small) equates to one Whopper (large), and the Whopper equivalency, small Whoppers to gallon of gasoline, is about 2,714. Note please that this is USA liquid gallons, not to be confused with the Imperial Gallon that the British and Canadians use, or the “Dry Gallon” that is sometimes used. The Imperial gallon is 20% greater than the USA gallon, i.e., 5 Imperial gallons are equivalent to 6 USA liquid gallons.

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  4. Wilson R says:

    Move closer work and commute on a bicycle. It’s the most efficient mode of transportation on earth. Americans, being extraordinarily lazy, will think that I’m kidding with this suggestion. Not only will you save on gas, insurance, vehicle maintenance etc.., you will be in much better health by the end of the month.

    • Mike B. says:

      Unless you plan to restructure civilization as we know it, commuting by bicycle is not a viable solution for the vast majority of motorists. I’m not lazy, I ride about 1000 miles annually but I simply couldn’t keep my job if I didn’t have motorized transportation.

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    • falcodoug says:

      have been riding a bike and motorcycle to work everyday now for over 20 years, 22 miles each way now. Rain or shine it is possible for some if you don’t need to take the grid lock freeways. Two wheels forever.

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      • falcodoug says:

        But I will walk before riding an electric or Hydrogen bike

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        • Dave says:

          Biking more than 1 or 2 miles is not feasible. I have ridden a motorcycle to work for 30 years except during the cold winter months. It is the perfect option for commuting. I get 58 mpg and my insurance is $10 per month. Motorcycle community is unheard of in the crowd that preaches ‘green’ solutions.

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          • Wilson R says:

            I ride my motorcycle to work these days, but when I lived closer to work I would take the bicycle. If gas ever becomes unavailable, we will be using alternative transportation. BTW, Long Beach just installed new bicycle lanes and car drivers are complaining non-stop about what a inconvenience it is to have bicycles share the road with them. I wish there were bike-specific lanes everywhere and then a lot more folks might try pedaling to work.

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  5. todd says:

    Perpetual motion has not yet been achieved. In every energy storage scenario you are required to input more energy than you ever will get back out of it.

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  6. kpaul says:

    Reality check: The U.S. coal reserves are capable of meeting domestic demand for more than 250 years at current rates of consumption. (from clean-energy.us). It’s cheap, reliable, proven. Electricity is like BoxerFanatic said a transmission method. So it all falls back to what is the most cost effective primary energy source. Hydrogen is costly to make compared to coal. Natural gas is a good supplement and great for heating homes but can’t supply the massive amounts of power needed for new transportation system not based on oil (by the way the U.S. oil reserves are only capable meeting domestic demand for 3 years according to USGS data)

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    • Paul says:

      250 years of you, me, China and India burning coal? Sweet! The earth’s surface will be 400F and our wretched descendants will be living deep in those handy coal mines fighting to the death over the last can of Spam. Yum.

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    • e-bob says:

      What would “current rates of consumption” be if everyone was running their vehicles on electricity? Unknown….

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    • Tom Barber says:

      “Natural gas is a good supplement and great for heating homes but can’t supply the massive amounts of power needed for new transportation system not based on oil”

      I don’t think this is the right way to look at natural gas. Demand will fluctuate depending on what changes we make with how we use it. This makes it difficult to predict how long it will last, and there is also significant uncertainty in how much there is within the USA. But the best estimates suggest that at the present rate of consumption, it will last at least another century. It just does not make sense to me to attach the label of “supplement” to natural gas but not to coal. There are of course still people who do not believe that global warming is real or that the contribution to this effect from burning hydrocarbons is appreciable, but for people who don’t disbelieve these things and for whom these concerns is a part of their reality, there can be no question that natural gas is much cleaner than coal. This is due to the fundamental fact that the ratio of carbon to hydrogen is far lower for natural gas than for coal. The perspective of electrical power as a means for transmission of power is appropriate as concerns at least electrical power that is generating from burning hydrocarbon fuel. The efficiency consideration is pertinent, and it follows that natural gas has an advantage over coal because cars can be converted to burn natural gas directly. Environmentalists argue that even the coal-burning power plants should be converted over to natural gas without delay. There is already a substantial pipeline network for natural gas distribution, even more substantial than the pipeline distribution system for gasoline, owing to the universal use of natural gas for heating. Filling stations for natural gas do not represent any sort of substantial investment in infrastructure, any more than stations where you can charge the battery in your electrical-only vehicle, but there is of course a big difference in how long you have to wait for the recharge, during which time your car is taking up space. When you consider how congested gasoline filling stations get during certain times of day, the prospect of electrical-only vehicles remaining withing the filling station for a period 100 times greater does not present a rosy picture. Electrical-only vehicles will fill only a small niche. GM of course realized this and put a small gasoline engine in the Volt, but evidently they kept this a secret until recently. Hybrid cars are a different matter; they make perfect sense other than the concerns with battery cost and disposal. Those concerns are valid, but notwithstanding those concerns, the direction in which we should be trying to push the technology in the near term should be toward hybrid vehicles and vehicles that burn natural gas in lieu of gasoline. There are companies that specialize in converting existing vehicles and their existing engines over to burning natural gas instead of gasoline. I have no doubt that it is not dirt cheap, but obviously it works. As soon as natural gas filling stations become commonplace, more people will be willing to have the conversion done, or else will choose a natural gas vehicle for their next car. There is no incompatibility between hybrid vehicles and natural gas. In fact, the hybrid vehicles on the road already could be converted over to run on natural gas instead of gasoline.

      And I have saved the best for last. In addition to all of the above rational that strongly implies that we should be converting all of our gasoline-burning vehicles over to natural gas, there is this reason: we get natural gas from North America, not from the Middle East.

      If the government endeavors to push the technology in certain directions, the government should push the technology in favor of natural gas. We have subsidies and tax breaks for every sort of crazy idea under the sun. Until recently, we even had federal subsidies for tobacco farming (and may still do for what I know). Why not tax breaks and subsidies for the installation of natural gas filling stations, to include pumps at existing filling stations, and why not tax breaks and subsidies for conversions of existing vehicles to natural gas, and tax breaks for buying a new vehicle that burns natural gas, on top of the tax break that applies for hybrid vehicles?

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  7. Chris #2 says:

    This may be a viable technology for our grandchildren’s generation. But for the here and now Natural Gas is the most practical alternative to $4 a gallon gasoline. Everything’s already in place, and our known reserves if used for motor fuel are equal to several hundred years at current usage.

    Another practical alternative is synthetic gasoline and diesel from coal. That technology has been around for 70 years, it’s what fueled the Nazi war machine (any oil wells in Germany? No, but plenty of coal). South Africa get’s something like 30% of their gasoline and diesel this way (called the Fischer Tropsch process if you want to read up on it). And the US has the vast majority of the worlds coal reserves.
    We should be developing these practical, proven solutions instead of all these gee whiz solutions that rely on exotic unproven technology that would require a complete retooling of our existing infrastructure.

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    • kpaul says:

      Yep totally agree. We have enough coal to support our current consumption for 250 years.

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      • GaryF says:

        Source, please. It’s not that I doubt you; it’s just that I doubt you.

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        • Chris #2 says:

          From the Michinac Center for Public Ploicy, Russ Harding Feb. 2009:

          http://www.mackinac.org/article.aspx?ID=10272

          “The most compelling argument for CNG vehicles is that abundant natural gas reserves in North America (assuming those reserves are allowed to be developed), could substantially reduce or eliminate our dependence on foreign oil for the transportation sector. This is a significant advantage to CNG as no other suggested alternative comes as close to achieving the goal of U.S. energy independence”

          From the June 2006 Pittsburgh Gazette:

          “SECUNDA, South Africa — Every day, conveyor belts haul about 120,000 metric tons of coal into an industrial complex here two hours east of Johannesburg.
          The facility — resembling a nuclear power plant, with concrete silos looming over nearby potato farms — superheats the coal to more than 2,000 degrees Fahrenheit. It adds steam and oxygen, cranks up the pressure, and pushes the coal through a series of chemical reactions.
          Then it spits out something extraordinary: 160,000 barrels of oil a day.
          daily production now meets about 30 percent of South Africa’s transport-fuel needs.

          Shenhua Group, China’s largest coal producer, has started work on China’s first commercial coal-to-oil facility, designed eventually to produce as many as 200,000 barrels of oil equivalent a day. Although that plant uses a different process from Sasol’s at Secunda, Shenhua officials are in negotiations with Sasol to jointly build at least one additional 80,000-barrel-a-day plant using the South African company’s technique.”

          “two senators from coal-producing states, Barack Obama of Illinois and Jim Bunning of Kentucky, introduced a bill to offer loan guarantees and tax incentives for U.S. coal-to-liquid plants.”

          Read more: http://www.post-gazette.com/pg/06229/714268-28.stm#ixzz1E4UeKIhY

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  8. BoxerFanatic says:

    Electricity is not a primary energy source, unless you are Doc Brown, and can capture a bolt of lightning.

    Electricity is an energy transmission format that has to be generated from other energy (usually a heat source… like fossil fuels…)

    And it doesn’t even transmit without losses in heat and electric field generation. You get less out at the end of the line than you put in at the beginning, unlike most pipelines.

    Hydrogen is not naturally occurring in mass quantities of uncombined molecules. Hydrogen is one of the most reactive elements, and combines with organic compounds or oxygen, or lots of other things very easily. It takes a lot of energy input to separate hydrogen from water or other molecules. Plus then you have to keep the hydrogen from either re-combining with other elements, or from leaking through materials with loose molecular structures. Plus you have to keep it cryogenically condensed to have enough volume in a portable tank to be of any use.

    The physics and chemistry just don’t support mass marketing and widespread use, until some new gestalt-shift scientific break-through comes along, and those can’t be predicted or planned for, because they may never happen.

    Even in biology, animal and plant life on this planet don’t use direct hydrogen for energy, and don’t have batteries, either. Bioelectric aspects are vital for signals, but bioelectricity is not primary fuel for biological organisms, either.

    Organic chemistry is the methodology of how life on this planet uses energy, because it is the most feasible format. Petrochemicals are an area of organic chemistry, and petrochemicals also make the most sense, just as the article states, it is hard to beat gasoline’s feasibility and energy density. Natural Gas is also an alternative, even if they are fuels for on-board electric generation, if generating and using electricity on-board a car turns out to be more efficient that using kinetic energy directly, without an electrical middle-man between the fuel to kinetic energy conversion, and using kinetic energy to move a vehicle.

    Wishful thinking doesn’t change the laws of physics and their application to chemistry, or chemistry’s impact on biology, or engineering.

    BTW, I wish we got that 5-door sedan version of the Mazda 6 in the US… especially if it had Mazdaspeed power and AWD like the previous generation Mazdaspeed 6. Although I’d choose a different color than Lilac colored paint.

    • Old town hick says:

      I had a gestalt-shift system in an old car that I once owned. It might have been German but I am not sure, it could have been any brand. It was really balky and clunky, and was very reluctant shift or move forward until I began driving it to the mass market. Everyone there wanted it to shift more and more during each visit, and they kept the pressure on until it finally found a way to do so. It was as if it would not have until MADE to by these forces that were eventually impossible to ignore or resist. It was tough and challenging…but I guess it really had no other choice.

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  9. kpaul says:

    Notice that the Obama administration recently announced a major shift away from federal funding away from hydrogen and clean diesel (bio-diesel) towards electric vehicles. Smart move. Like or not the market will decide. Electricity produced by coal, nuclear, solar, wind and hydro cost far less than producing hydrogen. Electricity already has the infrastructure in place. The U.S. has plenty of proven coal and uranium reserves. Lots of wind and sun as well. Solar panels and wind turbines are increasing in efficiency.

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    • MAR says:

      As soon as the Obama administration starts OK’ing and actually promotes Nuclear plants built and operating in the US, I will start believing that he actually believes in Electrical vehicles. He wont.

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      • kpaul says:

        I agree. Unfortunately you are probably right. Meanwhile other countries like France continue to expand their nuclear power generating capacity. It’s all about risk and return. Unfortunately with nuclear power people get too emotional here in the U.S. after the Three Mile Island disaster.

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        • Tom Barber says:

          People should get emotional about Three-Mile Island, and also about Chernobyl.

          If I could predict the future and could know with reasonable certainty that all future generations will fully embrace nuclear power, I would have far fewer reservations. But there is a possibility that I cannot rule out, where at some point not so far into the future, all of the world’s electrical power needs would be provided through solar, wind, hydro and geothermal, such that from that time forward, there is no reason for nuclear power. This does not seem at all out of the question to me. Maybe it is a hundred years away, or maybe two hundred years. But even if it is a thousand years away, it still does not seem right that people from that point forward should have to monitor the nuclear waste created by people during only a brief flash of time, in the grander scheme. If I could completely rule out this possibility, I would be more inclined to embrace nuclear power. But I cannot rule out this possibility, and I think it would be a shame if it were to play out this way.

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          • Mr. Mike says:

            Nuclear power technology has come a long way since the early 70′s when TMI and Chernobyl reactors were built. Think of all the reactors in continuous operation all over the world that have NOT had major incidents. You’re probably much safer sleeping with a nuclear reactor nearby than you are commuting to work by motorcycle.

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    • falcodoug says:

      Solar panels and wind turbines?

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      • kpaul says:

        “The unpopulated area of the Sahara desert is over 9 million km², which if covered with solar panels would provide 630 terawatts total power[citation needed]. The Earth’s current energy consumption rate is only around 13.5 TW at any given moment (including oil, gas, coal, nuclear, and hydroelectric)” from Wikipedia Just for fun :)

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        • steve says:

          thank you for saving the world kp!

          let me ask you…. is there any subject that you are not an expert on?

          do you ever listen to yourself?

          & if so…. do you even hear what you are saying??

          ROXX is right

          • Tom Barber says:

            ” .. is there a subject that you are not an expert on … do you even hear what you are saying”

            ????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????

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  10. Vrooom says:

    I wouldn’t say a nice lunch. Thanks for the article Gabe, I love any article that mixes motorcycling and science. With 3 times the energy density one thinks some track records will be shattered when this technology emerges.

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  11. GaryF says:

    Electrical power is the future. It is possible, however, that a hydrogen-powered “furnace” will be used to satisfy your power needs.

    Electricity is the lowest common denominator, like it or not.

    Hydrogen tankers, hydrogen filling stations, hydrogen production … all are decades away, at best.

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  12. Rich says:

    …(yes, I know it takes more energy to generate hydrogen than it stores)…

    You gloss over this way too lightly. Until it’s overcome, it’s not a viable solution.

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  13. Shannon says:

    I wouldn’t count out electric. Cornell has made great strides on a carbon nanopore lithium battery that increases energy density by a factor of TEN, which they say will have immediate manufacturing feasibility. I think we will see this implemented by the end of this decade. Various companies have floated the idea of battery changing stations (an idea with many potential foibles, I admit.) But I love the idea of being able to charge up at home. It would increase the load on the grid, for sure, but we as a nation would have many more options for putting electricity into the grid than we would putting fuel in our tanks – anything from solar to nuclear.

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    • kpaul says:

      “it would increase the load on the grid, for sure, but we as a nation would have many more options for putting electricity into the grid than we would putting fuel in our tanks – anything from solar to nuclear. ” Excellent point Shannon! :)

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  14. Dusty says:

    Hydrogen is more likely to replace Gasoline then electric IMO.

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    • Tom Barber says:

      The likelihood of hydrogen replacing gasoline in our lifetimes is essentially zero. It will never, ever happen for motorcycles or smaller cars, simply because of the problem with respect to the required volume for the tank, which, as I explained, would need to be more than ten times larger than the tank used to store gasoline. This is simply the nature of liquified hydrogen, and will not change. Alternate forms of “hydrogen”, in the form of hydrides, are not hydrogen, any more than gasoline is hydrogen, or any more than water is hydrogen. Some sort of hydride-based alternative fuel will likely not have the same problem with respect to the size of the tank, but this is only the most obvious of the various problems with using various sorts of rocket fuel to power regular passenger vehicles, and it isn’t truly hydrogen unless it is truly hydrogen.

      It is not entirely out of the question that at some point vehicles that use electrical power as the primary power source would make up the substantial majority of vehicles on the road. In fact, there is reasonable likelihood that this would eventually occur. But no matter how small the likelihood of this happening, this is still a much greater likelihood than the likelihood of hydrogen replacing gasoline, which has zero likelihood.

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  15. Old town hick says:

    For motorcycles, no matter what fuel source eventually replaces gasoline, the basic riding experience will be altered significantly. Four-stroke engines with manual gearboxes have characteristics that are different from anything, it seems, coming down the pike. The torque curves, compression-derived engine braking, sound, and effects of clutch use are “hard-wired” into the brains of CURRENT riders. Especially where riding is an enthusiast-driven activity (such as in the U.S.), the effects of electric, CNG, or whatever alternate power source may be a bit jarring.

    But change will come, and eventually newer generations be introduced to a fundamentally different motorcycling experience, and they will be OK with it. The internal combustion models that we now consider “the norm” will seem qauint and unusual, and there will less and less of them as time goes on. Thirty years ago snowboards were the rare and sometimes distained exception on ski slopes. Now actual skis are the minority (perhaps the runs should now be call “board slopes”).

    I think I want to ride four-stroke gasoline-powered bikes with six-speed trannies for the rest of my motorcycling days, but it seems clear that my grandchildren probably won’t do the same…and I guess that is OK. But will these new contraptions even still be called MOTORcycles?

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    • Tom Barber says:

      Engine braking is due to friction, not compression per se. If you were to build a new engine but forgot to install the valves, there would be no appreciable change in the amount of engine braking were you to coast with that engine coupled to the transmission in the usual way such that the pistons are forced to move back and forth fifty or so times per second.

      On the compression stroke, the temperature of the air within the chamber increases. The increase in temperature is the manifestation of an increase in energy content. The quantitative increase in energy within the gas is equivalent to the corresponding decrease in vehicular kinetic energy. But on the subsequent stroke, when the volume of the chamber returns to what it was prior to the compression, this gain in energy is returned to whence it came. Except for the amount that, via friction, goes to increase the temperature of the engine and eventually manifests as an increase in outside air temperature, there is no net decrease in vehicular kinetic energy.

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      • todd says:

        There is not much friction going on inside an internal combustion engine. The only truly affective source of engine braking is through pumping losses. Those pistons are trying to move a lot of air. Lets build your theoretical motor this time with the valves but forget to install the camshaft. Engine braking will be substantially reduced since it is not trying to pump air in and out of the valves. There is still a large amount of air being moved around the crankcase by the other side of the piston but the crankcase is large enough to reduce the effect. Think about the “Jake Brake” for a moment.

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        • Tom Barber says:

          Do not think about the Jake Brake, because it will confuse you. With a Jake Brake, the exhaust valve is opened at or near TDC to release the pressure before the energy transferred into the high-pressure air within the chamber is given back. A different scheme completely. Don’t go there. We’re talking about ordinary engine braking.

          When we are talking about engine braking, we are talking about friction on the moving parts of the engine. It is best to keep this simple perspective, because it is the physically correct perspective, and with this perspective, it is easier to keep focused on the effects that genuinely lead to engine braking. To slow down the engine, friction has to be applied, in order to convert some of the overall kinetic engine (which includes the kinetic energy of the engine and also the kinetic energy of the vehicle) to heat energy.

          Pumping losses influences both the volumetric efficiency and thermodynamic efficiency of an engine. With respect to both, the major culprit is the throttle. With respect to engine braking, we are concerned with engine friction, one component of which is aerodynamic drag on the moving parts of the engine. Taking the crankshaft for example, there is friction in the bearings, to include the bearings at both ends of the piston rod, but there is also air in the crankcase, which leads to aerodynamic drag on the spinning crankshaft. But the throttle restrictor is not a moving part per se of the engine, i.e., its motion is not directly linked to the rotational motion of the engine. The movement of the valves is of course linked to the rotational motion of the engine, so there is the potential for the aerodynamic drag force acting in opposition to the movement of the valves to be a factor in overall engine drag. The obvious question is whether that contribution would be significant in relation to all the other sources of engine friction. The aerodynamic drag on the crankshaft is without question significant, but it does not go away when you remove the valves. The valves move at high velocity for short time durations, but remain stationary most of the time. When the intake valve is opening, it is actually assisted by force of air as the air enters the chamber. When the intake valve is closing, the pressure in the chamber has reached a transitory peak, due to oscillatory effect, and is again assisting the motion of the closing valve, although the effect is likely negligible. The effects for the exhaust valve will be essentially the opposite, i.e., the flow and force of air in the chamber acts against the motion of the exhaust valve as it tries to open. It is not obvious to me whether the force of air on the exhaust valve will act to assist vs. oppose the exhaust valve as it tries to close, but either way, it is probably not appreciable. When you consider all of these factors together, the fact that aerodynamic drag at the throttle restrictor does not act to slow down the engine, the fact that aerodynamic drag on the moving parts of the engine is one of two types basic types of engine friction, the fact that aerodynamic drag on the crankshaft is likely far greater than aerodynamic drag on the valves even if the aerodynamic force on the valves were full-time and always in opposition to the motion of the valves, the fact that the valves are moving only a fraction of the time, the fact that aerodynamic force on the intake valve assists rather than opposes its motion, I am reasonably skeptical of the proposition that aerodynamic drag on the valves contributes significantly to engine braking effect.

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      • Bud says:

        I read and reread your second paragraph and honestly I don’t know if what you are saying is so far over my head that I have no idea whether it’s accurate or whether its a complete load of nonsense designed to baffle everybody.

        But I do know that installing higher compression pistons makes for increased engine braking. I don’t attribute that to increased mechanical friction.

        Therefore, I’m inclined to think the latter.

        Feel free to explain it more slowly if that will help me understand.

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        • Tom Barber says:

          Bud,

          There is nothing in that second paragraph that is not elementary physics of engine operation, so I can’t imagine why it would be over your head if you understand much at all about the underlying physics. When the piston acts to compress the air, the pressure increases, and as it does, the force acting on the piston face increases. Work is equal to force multiplied by distance. It follows that the piston is required to perform work in order to compress the air. Energy is required to perform this work, and it is consumed in a sense, but energy does not vanish. The compression of the air is much the same as the compression of a spring. If you compress a spring, you perform work and as you do so, you increase the energy stored within the spring. The amount of energy that you add to the spring is quantitatively the same as the amount of work you perform in order to compress it. When you allow the spring to expand, the situation is reversed. The spring now performs work, and the energy that was used toward the compression of the spring is given back. In a metal spring not all of it is given back. We say that there is friction within the spring. The temperature of the spring increases, which represents a gain in energy, but this is energy that is not given back. An air spring does not behave quite the same, because gas does not have the same thermodynamic properties as a metal spring. An ideal gas will heat up when you compress it, but as long as don’t let any of the heat escape, it will return to almost exactly the same temperature that it had previously, when you allow it to expand back to its original volume.

          I have a bit of an issue with you implying that what I wrote was a “complete load of nonsense designed to baffle everybody”. It was nothing of the sort, and you had no reason at all to reach that conclusion or to say that. When someone says something that you do not understand, it is perfectly reasonable to say that you do not understand and to ask for additional clarification or an alternative explanation. It is not appropriate to make accusations of the sort that you made until at least you are entirely certain that what you had read was only hot air (pun intended to prove that I have a sense of humor). Even in cases where someone writes something that is bogus, it is not appropriate to make those sorts of accusations unless there is compelling evidence as to the intent of the person who had written something bogus. People often assume that they are able to infer other people’s intent, but this is very rarely the case, and it is assumptions of this sort that lead to ill will.

          Finally, as for the effect of higher compression pistons. If you read the paragraph above you should now realize that what you believed to be true is simply not true. Engine braking reduces simply to friction on the moving parts of the engine. In order for any effect that is alleged to influence friction to be able to influence engine braking, it must be apparent how that effect contributes to friction on the moving parts of the engine.

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    • Old town hick says:

      OK,OK, enough about engine braking already! Please read beyond this very specific term, and consider the overall point of the post.

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  16. Tom Barber says:

    The reason that hydrogen fuel sounds too good to be true is because it is too good to be true. There are misunderstandings at various levels. At one level, there is confusion between energy density and specific energy. Yes, hydrogen has a very high specific energy, which is the energy you get relative to mass, which is linearly related to the energy released per individual reaction where two hydrogen atoms combine with a single oxygen atom to produce water. This is why it makes a good fuel for the space shuttle, i.e., low mass relative to quantity of stored energy. But for more down-to-earth applications, we are concerned with energy density, which is the energy quantity relative to volume as opposed to mass. When hydrogen is compressed into a liquid, its relative density (a.k.a. “specific gravity”) is only about 7%. This is directly due to the small mass of the individual atoms, which contain but a single proton in the nucleus. The fuel tank would need to be more than ten times larger than the fuel tank used to carry gasoline, to carry the same quantity of energy. When hydrides are used as a means to carry hydrogen, this does not improve the problem. The density of the carrier fuel will of course increase, but only because you are mixing a large amount of small pieces of heavy mass in with all the hydrogen. And when you do that, there is the additional effect of reducing the energy associated with each individual hydrogen atom, because it takes energy to release the hydrogen from whatever other atoms it is bound to. The extreme case would be water of course, which is a hydride, which is about 14 times more dense than liquid hydrogen, but which is useless as a fuel (notwithstanding that from time to time you read about how some mad scientist somewhere has come up with a way to use water for fuel).

    Beyond the confusion between specific energy and energy density, there are greater, more fundamental problems with hydrogen as a fuel for vehicles. It was once hyped as cleaner because supposedly in the production process half of the CO2 released when it is produced from raw hydrocarbons can be pumped back into the ground. It is not the least bit likely that it will stay in the ground for any useful amount of time on the grander scale that matters, and this is the same problem with the notion of “clean coal”. The notion of hydrogen as fuel to replace gasoline was thoroughly debunked in the book “The Hype about Hydrogen”, which is universally regarded as an authoritative, science-based analysis of the prospect of hydrogen as a replacement for gasoline. Yeah, if there were a pure source of liquid hydrogen somewhere on the planet, then this would be fantastic, but hydrogen is not like water or crude oil. It has to be manufactured, which is to say, you have to start with something that has hydrogen in it, the most obvious example being naturally occurring hydrocarbons, and then you have to extract the hydrogen.

    Forget about hydrogen as a replacement fuel for gasoline. It ain’t happening in our lifetimes, and may never happen. The best fuel for the USA to be pursuing at the present time, as a viable substitute for gasoline, is natural gas.

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  17. Herbert says:

    when technology fails…and it will, we’ll all be back on horses…and then we’ll all be on one horse power

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  18. MGNorge says:

    Diesel motorcycle? I don’t know about you but any diesel bike would have to be turbo charged or it would be about as exciting as watching paint dry! With that, any diesel would have to be multi-cylinder to extract as much performance as possible and even at that I’m not sure the riding experience would be anything like today’s bikes. Then there’s the extra cost that diesel brings with it. At the end of the day any diesel would still be using oil.

  19. GMan38 says:

    The amount of oil reserves in the U.S. are estimated to provide enough oil for 300 years, at the current rate. With the tapping into the Bakken field in ND and Eagle Ford in TX, some of this oil is finally being brought to market. There’s also huge reserves in Alaska’s ANWR, as well as the shallow waters of the Gulf of Mexico. I have no idea why the oil companies have to go out to deep water to drill, where a leak a mile below the surface is almost impossible to stop, as we’ve recently seen. Unfortunately, most of the energy in an internal combustion engine is lost through heat, and as much as 15-20% of power thru the drive train. Improvements through engineering are needed, but will no doubt ad $$$$$ to vehicle costs.

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    • kpaul says:

      Not so U.S. according to the USGS has only about 3 years of proven reserve at current consumption rate. The ND find would only last 6 months at our daily consumption rate. Proven oil reserves in the United States are 21 billion barrels, excluding the Strategic Petroleum Reserve. Currently, the United States consumes 19.6 million barrels per day, of oil. That is about 7.1 billion per year. So now you know why we are importing so much oil. Drill baby Drill won’t help. Electricity made by coal, nuclear, hydro, solar is the future.

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      • ROXX says:

        Kpaul, we’ve heard your tired, worn out, false arguments, loud and clear.

        Just stop the rhetorical comments that are flat out false.
        You are such a “know it all” and you lack descency in the way you discuss with those you disagree with, because of the way you talk down to others in such an arrogant manner.
        I can provide you with thousands of links reporting about how much oil we DO have here in the good ole USA, but you are going to believe the reports that you want to believe without reason, just because you are so stuck on electricity.
        Please let us all know, do YOU personally own and drive electric bikes and cars only?

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        • Dave says:

          1000′ of links would be more than anyone wants to sift through. How about 3 links from reputable sources?

          kpaul offers numbers and names his source.

          There are good reasons we haven’t already tapped the oil that we do have, the main one being that it’s far more expensive than buying foreign oil. Oil companies exist to make money, they’d have done this already if it could be profitable for them. Besides that, I have never seen any reports that paint the picture of a 300 year supply, nevermind one that addresses the fact that the current rate of use will continue to change rapidly. I’m certainly interested to though.

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          • Joe says:

            Sorry Dave your reasoning why were not drilling is dead wrong and you know it.Its environmental reasons, THE EPA has entirely to much power, also notice all the land closures for off road vehicles the EPA has caused.

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          • Dave says:

            I don’t know that and neither do you. Oil and natural gas are exempt from the clean water act. Natural gas extraction is turning people’s tap water flammable and poisonous. The EPA has done nothing about that. The lobbyists that got those permissions will get permission to drill as soon as it is profitable.

            http://www.ewg.org/reports/Free-Pass-for-Oil-and-Gas/Oil-and-Gas-Industry-Exemptions

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          • Joe says:

            Dave there are moratoriums on drilling on the coast of California, on the east/southern coasts of Florida, in the Gulf of Mexico and in Alaska that I am aware of. The EPA also has the ability to put moratorium on area if they think the Wildlife is affected, so it is not just the ocean that they have the control over. Also Obama put a 6year moratorium on deep water drilling last year.I believe all these area above are not counted as of available oil.

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        • kpaul says:

          Thanks Dave. Here are the links to my sources
          Coal Reserves: http://www.clean-energy.us/facts/coal.htm
          Oil Reserves: ND find: http://pubs.usgs.gov/fs/2008/3092/
          http://energy.usgs.gov/

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        • Bud says:

          I don’t detect any arrogance or lack of “descency” in kpaul’s post. I too am interested to see your contradictory proof. Put up or shut up.

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        • steve says:

          here’s some info…

          America is sitting on top of a super massive 200 billion barrel Oil Field that could potentially make America Energy Independent and until now has largely gone unnoticed. Thanks to new technology the Bakken Formation in North Dakota could boost America’s Oil reserves by an incredible 10 times, giving western economies the trump card against OPEC’s short squeeze on oil supply and making Iranian and Venezuelan threats of disrupted supply irrelevant.

          In the next 30 days the USGS (U.S. Geological Survey) will release a new report giving an accurate resource assessment of the Bakken Oil Formation that covers North Dakota and portions of South Dakota and Montana. With new horizontal drilling technology it is believed that from 175 to 500 billion barrels of recoverable oil are held in this 200,000 square mile reserve that was initially discovered in 1951. The USGS did an initial study back in 1999 that estimated 400 billion recoverable barrels were present but with prices bottoming out at $10 a barrel back then the report was dismissed because of the higher cost of horizontal drilling techniques that would be needed, estimated at $20-$40 a barrel.

          It was not until 2007, when EOG Resources of Texas started a frenzy when they drilled a single well in Parshal N.D. that is expected to yield 700,000 barrels of oil that real excitement and money started to flow in North Dakota. Marathon Oil is investing $1.5 billion and drilling 300 new wells in what is expected to be one of the greatest booms in Oil discovery since Oil was discovered in Saudi Arabia in 1938.

          The US imported about 14 million barrels of Oil per day in 2007 , which means US consumers sent about $340 Billion Dollars over seas building palaces in Dubai and propping up unfriendly regimes around the World, if 200 billion barrels of oil at $90 a barrel are recovered in the high plains the added wealth to the US economy would be $18 Trillion Dollars which would go a long way in stabilizing the US trade deficit and could cut the cost of oil in half in the long run.

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      • Herbert says:

        you guys all need to get your heads out of your arses, does any of it matter? No. enjoy what we have, hope for something better, become part of the solution, otherwise shut your hole.

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  20. Mike says:

    Fossil fuels may be 20% efficient and electric motors 75% efficient, but the efficiency to create the electricity in the first place is ignored. Electricity isn’t “free”.

    Future portable energy sources, whether electric or hydrogen based, are going to require tremendous amounts of energy to create the mobile “fuel”. Solar & wind are hopelessly weak from an energy density standpoint, and that means nuclear and hydroelectric are the way to go.

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  21. Harvey Mushman says:

    Hydrogen is explosive! Horrors! And gasoline is…explosive.

    Over-reached on that one.

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  22. steve says:

    yes, great article Gabe. A few years ago, all the talk was about hydrogen fuel cells, not electric/battery powered vehicles. Glad to see thay are still working on it. There were a ton of companies not too long ago working on fuel cell technology.

    The other thing about hydrogen is the network distribution issue – gas stations. I’m guessing they could be retrofitted to dispense hydrogen. Electric vehicles have a problem here…. there isn’t an existing method/network across the USA to dispense electricity to charge your battery powered vehicle & even if there was, the charge time is still far too long. Hydrogen has none of these problems.

    & it’ll NEVER run out….

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  23. Burt says:

    Come on. Michael didn’t really say “loosing”, did he?

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  24. Joe says:

    Its great knowing there are people out there looking for the next big thing, (to replace gasoline). It also makes you think about gasoline, for its reatively low price and amazing performance its still unequaled. Scientist and engineers all over the world are trying to produce a replacement for it and as of yet are not even close. There are wildly different scientific opinions of how much fossil fuels are left on earth, some think there still is an amazingly large supply, others think its on its last stretch. The answer is probably somewhere in the middle. Hopefully there is enough gasoline to span us until it can be replacement.

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  25. Hugh says:

    Hydrogen, even encapsulated hydrogen, doesn’t really solve anything regarding energy. You still have to make the hydrogen, and AFAIK the only way to do that on any kind of scale is via electrolysis of water into hydrogen and oxygen. THAT requires electrical energy to be generated by coal, hydro, nuclear, etc. Encapsulated hydrogen may turn out to be a better way to store energy than a battery, but it’s still effectively just a way of storing energy generated by other means.

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  26. secret asian man says:

    It is probably easier to make synthetic gasoline than it is to encapsulate hydrogen.

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  27. MikeD says:

    Keep at it Guys, someone someday somehow will hit the nail and it may be as easy,quick and efficient as filling up our tanks with gasoline some day.
    Meanwhile, let me have some more of that sweet 93 Octane Juice.
    Why don’t we have any big OEM making diesel motorcycles ? Or CNG fueled like Kirk66 mentioned earlier ?
    CNG i can see how a lack of infrastructure and support don’t help as there ain’t one CNG refill station around each corner as opposed to their gasoline counterpart.

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  28. kirk66 says:

    It’s not a bad idea. Here’s another. CNG! Compressed Natural Gas should be what we are concentrating on until the technology chatches up. Why? The good ‘ol US of A has the largest natural gas reserves on the planet. We are the world’s center for the stuff like the middle east is the center of the oil producing world. We’ve been powering forklifts, buses, police cars and power plants for decades with the stuff. It’s not like you can’t make a tank that can handle it. You’d have to do the samething for Hydrogen so the tank technology can transfer.

  29. Bud says:

    3 times the energy density of gasoline sounds like lots of horsepower potential! Let’s get going on that!

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  30. Rion Annassie says:

    Interesting article for the sake of techno babble, but I take complaint on one part “It’s the most abundant material in the universe,”
    Technically true, however most of that gas is in space gas clouds light years away, or in the Sun. On earth it comes mostly from Oil by products…. Aren’t we trying to break away from that stuff?

    but the geek in me liked the theory.

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  31. Austin ZZR 1200 says:

    Thanks, Gabe. Nice article (and stock tip). Though I would get a positive word in before the influx of e-hater mail..

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