A practical consumer fuel cell, coming soon
At CES 2008, I talked with several companies, some for work and some for Speeds and Feeds.
Although I saw many interesting products, I'm really looking forward to one product in particular that isn't due to ship until October.
The HydroPak fuel-cell power supply takes replaceable fuel cartridges and produces AC power.
(Credit: Horizon Fuel Cell Technologies)It's the HydroPak fuel-cell power supply from Horizon Fuel Cell Technologies. It produces up to 25 watts of power from replaceable solid fuel cartridges and water. A single refueling can produce about 270 watt-hours of energy through the HydroPak's standard 110V AC power outlet and two auxiliary USB power jacks.
This electricity is expensive-- $20 for a fuel cartridge, putting the cost of a kilowatt-hour at $74 vs. about a dime if you get it from a wall outlet. But as I described in a December post about the much larger, more expensive iGen fuel cell from IdaTech, the price of electricity in an emergency or when you're just out camping can be relatively high and still make good sense.
It's easy to get cheap electricity in the field. Buy a gasoline generator ($300 and up) and some fuel. Pull the starter, and you've got juice. But a generator is loud and smelly, and gasoline is dangerous. Nobody wants to listen to a noisy generator out in the wilderness. Nobody wants to smell one anywhere, and you can't use one indoors.
Also, a generator may produce much more power than you need. There's no such thing as a 25-watt gasoline generator. Even the smallest generators are barely portable. If all you need to run is a radio or a laptop, a generator is overkill.
But fuel cells aren't a good alternative today. I've written about tiny ones like the Medis 24-7 Power Pack (which I don't like because it's too small and much, much too expensive) and large ones like the iGen and the Trulite KH4. But there isn't anything in between--nothing priced like a gasoline generator but capable of producing useful amounts of power.
So that's where the HydroPak comes in. It's $400 for the main unit and $20 for the cartridges. The main unit weighs four pounds; one fuel load consists of a half-pound fuel cartridge and a little over a pint of ordinary water (which needn't be pure; even salt water is OK). The HydroPak can operate indoors; there's no exhaust. It's almost silent.
On one refueling, the HydroPak can recharge a notebook computer several times--maybe five times for a full-size notebook like the MacBook Pro I use, maybe 10 times for a small machine like the Asus Eee PC.
The fuel cartridges can be stored for years. They're safe to transport; Horizon is working on getting all the appropriate transportation safety certifications. You don't have to use the whole fuel cartridge at once after it's been activated.
The cartridges contain the same sodium-borohydride fuel that the Medis and Trulite power supplies use. It seems to be the best option right now, but it isn't perfect. It's offers good energy density, but it's still a corrosive, mildly hazardous chemical. As long as the fuel and the byproducts of the reaction, which are returned to the cartridge, remain securely sealed inside, everything's OK... and that means packaging may be the critical element of all these products. We'll just have to see how it all works out as consumer sales grow.
The other drawback of the HydroPak is the way power is drawn from the unit. That AC power outlet seems convenient, but the unit can only provide 25W of power--50W peak for brief periods--and most things that plug into an AC outlet draw more power than that.
My MacBook Pro has an 85-watt AC adapter, but the 85W figure is for its DC output. It's rated to draw up to 165 watts from the wall--although I think in practice it probably doesn't exceed about 100 watts. Even the AC adapter that came with my Eee PC says it can draw 74 watts of 110V power, though I think it probably really tops out at 40 watts or so. Will that work on the HydroPak? I'm not sure.
The USB power outlets are convenient for cell phones and other low-power devices (up to 2.5 watts each), but you can't charge a laptop or power tools from a USB jack.
It seems to me that what the HydroPak really needs is a high-power DC output--a traditional 12V cigarette-lighter jack or perhaps the Anderson Powerpole, which has become the standard 12V power connector in the amateur-radio field. It would be especially valuable if the HydroPak could charge standard 12V car batteries or smaller gel-cell batteries, because then an AC power inverter could be connected to produce much more than 25 watts of output power for shorter periods of time.
Anyway, I'm sure that Horizon and other fuel-cell providers will figure out what the market wants, and over the next few years we'll probably see a great variety of fuel-cell power supplies. But I think we'll be able to say that 2008 was the year that fuel cells first became true consumer products, and Horizon may be the first to get there.
Peter N. Glaskowsky is a technology analyst for The Envisioneering Group. He is a member of the CNET Blog Network, and is not an employee of CNET. Disclosure.
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sorry why is this product news again?
AliasMrJones-- it's true you can carry batteries that store as much energy as one of the cartridges for the HydroPak. But lead-acid batteries are heavy, and if you need AC power, you'll have to carry an inverter as well. To match the output of one HydroPak fuel cartridge you'd have to bring along about 30 pounds of equipment, and of course a HydroPak user can bring multiple cartridges.
You could bring lighter batteries, but a lithium-polymer battery pack with about 300WH of capacity costs about $500.
It just isn't practical to think about transporting large amounts of electrical energy in the form of charged batteries. A generator is much more efficient, whether it's a fuel-cell generator like this one or a gasoline generator. But a gasoline generator has some significant problems, which creates an opportunity for fuel-cell makers.
. png
I am hatching an idea for a startup. What is your opinion of the right power level, run-time, and cost to the consumer for a portable fuel cell product? (Probably water-methanol fueled, but not necessarily.) Would outdoor-only use be a terrible restriction? All other opinions welcome as well...
I'd make it a premium product, since it's a young market and you gotta make your money back somehow. Price it at $600 or so plus $20 for a day's fuel and it'll sell pretty well.
That's my off-the-cuff answer, anyway. For a more carefully considered, fully researched response... well, you might have to wait until I'm done with my current startup. :-)
. png
?Hydrogen beats batteries, biofuel and all other vehicle power solutions:
A. Hydrogen can be made at home and requires NO NEW INFRASTRUCTURE. Anybody who says it can?t be made at home or work is either a shill or completely out of touch with reality and technology. You can make it for free, at home, all day long and all night long. The production can be powered by solar, wind, microbes and other free sources. The volume of H2 produced ?IS? enough to charge solid state H2 containers. The metrics quoted by the anti-hydrogen crowd are just lies to protect their competing business interests.
B. It now costs less to make hydrogen from water than any known way to make gasoline and it continues to get cheaper every month: The GE Noryl system, The R4 processor and over a hundred different systems can do this NOW; with many more expected next year. The ?battery shill? spin has worn thin and has been supplanted by facts. Hydrogen is made from WATER via solar energy, wind energy, microbes, radio waves, sunlight and salt, and other FREE sources of energy. Hydrogen can also be made from any organic garbage, waste, plants or ANYTHING organic via lasers, plasma beams or dozens of other powered exotics which can be run off of EITHER the grid or the free hydrogen made from solar energy, wind energy, microbes, radio waves, sunlight and salt, and other FREE sources of energy OR the grid. There is no oil that needs to be involved anywhere in the production of hydrogen. These systems trickle charge hydrogen into storage containers, either tanks or solid state cassettes, 24/7.
C. Tens of millions of dollars are being spent by battery companies like A123, Cobasys, AltairNano, etc. in order to discredit hydrogen because hydrogen works better than batteries. A large number of ?pundits? who act as ?writers?, ?bloggers?, ?authors? and ?non-profit evangelist group founders? are actually supported by financial gain from battery companies who are terrified of hydrogen displacing their revenue streams. They include:
Ulf Bossel of the European Fuel Cell Forum,
Alec Brooks
James Woolsey
EV World
Sam Thurber
Cal Cars
Felix Kramer
Lets go over the battery and bio-fuel shills lies:
Lie # 1:
?But critics say the process of producing hydrogen requires three to four times more energy than the hydrogen later generates in the fuel cell.?
RESPONSE: This is data from the 60?s. It is now more efficient to make hydrogen than it is to make gasoline, build or use batteries or process bio-fuel. The technology has beat everything else.
Lie # 2:
?the cars are too expensive.?
RESPONSE: The production of hydrogen cars is at an early stage while battery cars have been around for almost a hundred years and the battery cars are still expensive for what you get. The Moore?s law on hydrogen cars shows a clear price decline to low cost in market volume. A Fuel Cell car that goes 500 miles without a charge costs half as much TODAY as a battery car that goes 500 miles without a charge.
Lie #3:
? hydrogen molecules can't be contained easily without energy-consuming compressors or maintaining them in liquid form at extremely low temperatures , and it's extremely difficult to store,"
RESPONSE: This data is also from the 60?s. Hydrogen is stored in chemical powders and muds that easily contain vast amounts of hydrogen. Pressure and liquid tanks to store hydrogen are old school archaic technologies. Hydrogen can be easily stored in over 2800 different solid state compounds.
Lie #4:
"The infrastructure isn't there?
RESPONSE: Solid state hydrogen can be shipped by UPS, Common Carrier and uses all existing infrastructure. DOPT has already licensed and approved such solid state delivery via common EXISTING INFRASTRUCTURE. This method can reavch every person on earth TODAY! This requires almost NO NEW INFRASTRUCTURE. NO INFRASTRUCTURE IS NEEDED!!! This is the biggest lie of all. A large number of start-ups have solid state hydrogen solutions that entirely use existing infrastructure.
Lie #5:
?the hydrogen is too expensive?
RESPONSE: Hydrogen can be made at home or office in numerous ways powered by solar or wind or microbes or any number of free power sources. It is always being made by such devices and constantly trickle charged into solid state storage systems all day and night FOR FREE without grid power. Hydrogen processors now make hydrogen with 91% efficiency.
Lie #6:
?Hydrogen is too dangerous?
RESPONSE: If the gasoline in your car blows up it will do a VAST AMOUNT more death and damage than H2 ever will. You are driving a MOLOTOV COCKTAIL. H2 on fire rapidly dissipates up an into the air. Gasoline flows all over people, cars and streets and covers all of the above with flaming death you can?t easily extinguish. In 2030 oil is GONE and there is NO OTHER OPTION that can be delivered world-wide in time but H2! Biofuel only solves 2% of the problem. Batteries have failed. Nuclear is too dangerous.
Lie #7:
?We have enough gasoline to last forever?
RESPONSE: Gasoline/petroleum/petrochemicals have now been shown to be the number one cause of cancer, and maybe the primary cause of cancer, in the world. Besides causing global warming, lung disease and all of the other bad things that it does; the oil industry itself knows that affordable oil is gone around the year 2030. Even if it wasn?t, do you really want the ROOT CAUSE OF CANCER around one day longer than it needs to be? (See the EPA report ?EPA/600/S-6-87/001 Sept. 1987? as one of over 16,000 studies validating this.)
A ?fuel cell car? and an ?electric car? ARE THE SAME THING. The shills want you to think otherwise. The only difference is where the electricity is stored. You can pull the batteries out of every Zenn, Tesla, Zap, EV1, Venture Vehicle, etc. and pop a fuel cell/hydrogen pack in the same hole and go further, more efficiently in EVERY SINGLE CASE.
A modern fuel cell and hydrogen system beats batteries on every front including
FIRE- Batteries catch on fire constantly and have been the result of massively more fires and explosions than hydrogen. AT&T 's U-verse TV service now has an exploding battery problem, making it necessary for the firm to replace 17,000 backup batteries in its nationwide network. The Federal Government has OUTLAWED Lithium Batteries on airplanes because they explode unexpectedly so often. Batteries blow up when-ever they want to.
Life Span- Hydrogen power systems run massively longer and provide massively greater range per charge than batteries.
Run Time ? The run time of batteries constantly shortens while hydrogen does not.
Memory Effect- This effect is not present in hydrogen systems
Recharge Time- modern hydrogen systems are instant recharge.
Charge life- Modern hydrogen systems can recharge massively longer than batteries before end of life.
Nano powder batteries have cancer causing powder that falls into the pores of the Chinese factory workers skin and gives them potentially fatal diseases
Cost- The cost per 300 mile range for a hydrogen car system is massively lower than a battery system. A hydrogen powered car TODAY that will drive 300 miles without a refill is 50% of the price of a battery car that will drive 300 miles without a refill.
Energy from ?sour-grid?- A modern hydrogen system can be charged from a completely clean home energy system.
Can?t make energy at home- Hydrogen can be made at home. Batteries cannot.
Storage Density ? Modern hydrogen technology has a massively higher storage density than batteries.
Bulky Size- Hydrogen systems are dramatically less bulky than batteries.
High Weight- The weight of batteries is so great ir reduces the reange of travel of a vehicle which causes the use of wasteful energy just to haul the batteries along with the car. Hydrogen energy systems weigh far less.
Environmental soundness- The disposal of batteries after use presents a deadly environmental issue.
Self Discharge issues- Hydrogen does not self discharge like batteries.
Batteries cause a greater carbon footprint than hydrogen
Battery shills are mostly paid for by military contractors.
The charge-keeping capability of a typical lithium-ion battery degrades steadily over time and with use. After only one or two years of use, the runtime of a laptop or cell phone battery is reduced to the point where the user experience is significantly impacted. For example, the runtime of a typical 4-hour laptop battery drops to only about 2.5 hours after 3,000 hours of use. By contrast, the latest fuel cells continue to deliver nearly their original levels of runtime well past the 2,000 and 3,000 hour marks and are still going strong at 5,000+ hours
The electrical capacity of batteries has not kept up with the increasing power consumption of electronic devices. Features such as W-LAN, higher CPU speed, "always-on", large and bright displays and many others are important for the user but severely limited by today`s battery life. Lithium ion batteries, and lithium-polymer batteries have almost reached fundamental limits. A laptop playing a DVD today has a runtime of just above one hour on one battery pack, which is clearly not acceptable.
Batteries require coal be burned to charge them. One pound of coal has roughly 14,000 Btu of chemical energy in it. Any reference textbook says that. When that pound is burned in an electric powerplant, steam is made, which drives turbines at high speed, alternators are turned, and electricity is made. When everything operates well, all that turns out to be generally around 30% efficient, meaning that 30% of the chemical energy that started out in the coal has become actual electricity.
So, for a pound of coal burned, your house electrical outlets then receive around 1,820 Btu of electrical power. Around 1100 Btu of that can actually get put in the batteries, due to efficiencies of battery chargers and batteries. Of the energy STORED in the batteries, the efficiencies of batteries, motors and gear trains are such that around 450 Btu of that are eventually available at the wheels as motive power. (Remember that this is out of 14,000 Btu of chemical energy that was produced when that pound of coal was burned!)
One watt-hour is equal to about 3.412 Btus, so this 450 Btus is the same as around 130 watt-hours, or, for a 14-volt automotive battery, around 10 ampere-hours of actual usable power. The 130 watt-hours is also equal to around 0.18 horsepower for an hour. Now, this might sound like a lot, but remember that the 14,000 Btu in the pound of coal resulted in this 450 Btu that is actually usable in a car, only about 3% overall efficiency! And the other 97% of that energy when the coal was burned all went toward heating that contributes to global warming.
In contrast, a gallon of gasoline has around 126,000 Btu of energy in it, of which a modern car converts around 21% into motive power, so there results around 26,000 Btu of motive power. POINT: Around 60 pounds of coal (with 840,000 Btu of chemical energy in it) must actually get burned to provide the electricity such that a battery-powered car can do the equivalent to a single gallon of gasoline! (60 * 450 = 27,000) (This is a VERY "losing proposition"!)
That amount of electricity that needs to go INTO the batteries in the car (to be equivalent to that ONE gallon of gasoline) is therefore the 1100 Btu per pound of coal divided by that 3.412 times 60 pounds, or around 20,000 watt-hours of electricity. That is a LOT of electricity! Say you will have 10 hours at night for the batteries to recharge. That means that you would have to have 2,000 watts of power constantly being used and feeding the batteries. For the 14 volt circuitry of standard batteries, that would mean that around 140 amperes of charging electricity would constantly be needed. (NOT the 6 amperes of a good battery charger!) (This huge charging current might actually cause the batteries to explode, unless they are a special and more expensive Deep-Discharge type of battery!) (Batteries in golf-carts are generally wired in series to reduce the amount of current needed.)
Even the house wiring involved might be in question! We are talking about a REALLY impressive battery charger, of course, akin to 25 conventional battery chargers used together, which requires that 1820 / 3.412 * 60 or about 32,000 watt-hours of input electricity. Over our ten hours, we are therefore talking about needing 3,200 watts of electricity constantly coming in to supply your battery charger. Your house electrical service is sufficient for this need, but standard house wiring would not be. If at 120 volts, a constant 30 amperes of house electricity would be needed, where normal house circuits are either 15 amp or 20 amp if heavy duty. This probably means you would need the specialized wiring like was installed for your air conditioner, which uses roughly the same amount of electricity, through a special 240 volt wiring made especially for the air conditioner. This means you need around 15 amperes of input power to provide that 3,200 watts at 240 volts, or about 30 amps if it is 120 volts.
Herein could be a problem, because most houses were built with 100-ampere electrical service If the A/C is running and this battery charger and some other electrical devices, you might get close to the full capacity of the house wiring! The existing house wiring, and even the transformers up on the utility poles, are barely big enough and could overheat at that constant heavy ten-hour load!
We haven't even yet considered the cost of all that electricity! When you think about a constant 10-hour long consumption of about as much electricity as your central air conditioner uses, you probably start to get the picture. But say you are in some wonderful location where electricity is still only 10 cents per kilowatt-hour. We are needing to use up 32 kilowatt-hours (to equal the vehicle performance of a single gallon of gasoline, remember), so that is 32 * 10 or $3.20 of electricity added to your house electric bill, for the equivalent to ONE gallon of gasoline! It does not initially APPEAR to cost anything, and the car merrily scoots around on its battery power. But if and when an owner realizes that they also have to spend at least $3.20 in extra electricity for each gallon of gas not used, much of the financial argument goes away!
You are encouraged to do research to confirm what is described above. It is all true. Did you notice the "worst part" of what is described above? I'm not even talking about the fact that you would wind up paying for at least $3.20 of house electricity to replace each $3 gallon of gasoline! In refining a gallon of gasoline, yes, significant energy is used up, although I have never been able to get a reliable figure. But certainly well under 840,000 Btu of refining energy is required to form the gallon (126,000 Btu) of gasoline. Replace all cars with battery-powered vehicles, and we then would NEED to burn 60 pounds of coal or use 840,000 Btu of coal (or nuclear) chemical energy to produce the equivalent effect of every gallon of gasoline. This is worse, regarding resource energy wastage, than the vehicles that are currently on the roads! (Yes, the energy is used up in a distant place, and maybe it seems possible to be able to be ignored, but that is still a really bad idea!) And virtually everything that does not contribute to the "motive power" winds up as wasted heat energy.
When those 60 pounds of coal were burned to create the needed electricity to duplicate the benefits of one gallon of gasoline, carbon dioxide is also released into the atmosphere. The coal is around 75% of bituminous coal, or 45 pounds of that. It is fairly simple to determine the amount of carbon dioxide that is created when it is oxidized. The amounts of carbon and oxygen have to be in a molal relationship of one to two. That means the weight relationship has to be 12 (the atomic weight of carbon) to (12 + 16 + 16 or 44) (the atomic weight of the molecule of CO2. This means that 44/12 or 3.67 times the weight of carbon dioxide is created, or in this case, 165 pounds, of carbon-dioxide would get released in this process. When a gallon of gasoline is burned in an automobile, it is less. A gallon of gasoline weights around 6 pounds, and it is about 83% carbon. That means that it contains nearly exactly 5 pounds of carbon in the gallon. Again using the 3.67 multiplier, we can see that only around 18 pounds of carbon-dioxide is released.
This means that global warming then would occur around 7 times as fast as now! (840,000 / 126,000 [heat]) or (165 / 18 [CO2]). If millions of people started driving battery-powered or Hydrogen-powered vehicles, it would therefore be a far WORSE environmental disaster than now, causing global warming to become even faster than it already is!
The "Ethanol adventure" of using 1/5 of the total farm crop production of 2006 for conversion to Ethanol, which provided only around 2% of the vehicle fuels we used in 2006, is simply endangering our near-term food supplies. News reports are already (April 2007) discussing higher milk, bread, beef, and many other food prices in our grocery stores, as a result of the massive focus on producing Ethanol. But some weather problem is bound to occur. Where we used to have massive over-production of nearly all crops, our government has planted the seeds of a true food-supply disaster, which could happen any year now. In 2008, it is expected that the amount of America's total crop production which will go to making Ethanol will be 1/3 of everything grown! It is as if we are totally crazy, or that we do not even give any thought to what might be a consequence next week or next month or next year! It really is amazing!
What are called Hybrid vehicles are promoted and sold everywhere already, cars that include both a gasoline-powered engine and a battery-powered electric motor. The promotions for them are unbelievably misleading to the public! They totally ignore all that electricity needed to charge the batteries, but then use the charged batteries to help it get very high fuel-efficiency numbers! People are buying such vehicles (which cost a premium because of their having to include two entirely separate sources of power) greatly because they are told they are GREEN and that they see those very impressive mileage numbers. Those are both very clearly pure lies! As to the GREEN part, we discussed above that the electric powerplant where the electricity was made necessarily produces around seven times as much carbon dioxide and heat loss as a gallon of gasoline produces directly.
As to the mileage figures, well, without recognizing that at least $3.20 of bought house electricity is needed to replace each equivalent gallon of gasoline (eliminating any actual savings), there are a LOT of other details that no one bothers to tell customers! Such as driving a Hybrid or battery-powered car at night consumes far more electricity for all the lights! Far less battery power is left to actually move the vehicle! And no one seems to mention that the battery-mode operation provides only roughly 10 horsepower maximum for the vehicle, meaning only low speeds and rather poor performance. And this deception is INTENTIONAL! TV ads for a Hybrid vehicle that has a 470 horsepower gasoline engine makes it seem that an owner can have his cake and eat it too! A driver who buys a car because it has a 470 horsepower engine is NEVER going to be satisfied with the performance during a 10-horsepower battery-powered mode of operation! There are many other drawbacks as well.
Another stupid-brilliant idea is manufacturing and selling vehicles that will only run on what is called E-85, meaning 85% Ethanol fuel. Again, if there were unlimited supplies of Ethanol, that might make sense. But when America uses up one-fifth of all its farm crop production to provide only around 2% of the amount of fuel that American drivers use up each year, it indicates scary thinking, or lack thereof. By the time the auto manufacturers fully perfect cars that they will be able to sell to run on E-85, and by the time there are enough service stations that even carry E-85 for such drivers, it is certain that some overwhelming crisis will occur (probably in a weather problem and severe shortages of food for Americans), where sanity might again briefly appear and the massive effort toward Ethanol will very suddenly end. For the few people who may wind up buying E-85 vehicles, they will merely wind up having something that might someday go into a museum, something like what happened to the Edsel automobile!
It is really sad that even supposed Regulatory Agencies of the Government have participated in this hype. A car that has a conventional engine, is likely to get the gas mileage that has long been known, somewhat UNDER what the EPA estimates say! But regarding Hybrids, they seem to have just considered the battery-powered miles to be "free" (because no gasoline is used) and they have listed some Hybrids as having 60 miles per gallon fuel efficiency. That is technically true, if you totally ignore the cost of all that electricity needed as calculated above! If they wanted to go even farther, they could set up a really short test procedure where ONLY the batteries were even used, and then they could let the manufacturers advertise "1000 MPG" or "1,000,000 MPG" or more! The person's home electric bill would go off the charts, but they do not seem to see any reason to consider that expense!
There is an extremely heavily promoted new vehicle being presented in the news in 2007. The Tesla Sports Car certainly can show impressive acceleration. However, both the media reports and their own web-site present some information that simply violates the laws of Physics! It would be wonderful if such things were possible, even in a $92,000 car.
Unfortunately, they clearly have done the common "spin" that spokespeople seem to all use today to deceive the public. THAT is really sad. Especially since this particular product actually can probably provide pretty decent performance. Why is it always seen as necessary to be deceptive today?
Using information from their own web-site:
First, there is a small-print, very faint, and very hard to read Disclaimer at the bottom of their web-pages that notes that their vehicles have not yet passed government safety testing, and they say that their specifications might change as a result of that. (By the way, since they have not yet passed government safety tests, they are not yet street legal in any State and could therefore not yet be licensed!)
First, they say that the car can produce an absolute maximum of 185 kW of electrical power. Since 746 Watts is equal to 1 horsepower, this is equal to 185/0.746 or 248 horsepower. They state in the same sentence that that is equal to 248 peak horsepower. That is fine.
They show a graph where the available torque is basically constant over a wide range of motor speeds (which is fine), and the same graph also shows the horsepower curve that is linear, rising from 0 horsepower at 300 rpm and rising to that maximum of about 248 horsepower at maximum speed. That is also fine, and in good agreement with science.
However that information can be mathematically Integrated to determine the actual acceleration, when one also knows the vehicle weight. The web-site gives the vehicle total weight as being 2,500 pounds.
We can first calculate some more things that DO agree with their claims, to show that at least those claims are credible. Let's consider their vehicle top speed. The streamlined shape of the vehicle certainly has a Coefficient of Drag of around 0.3. The total frontal area of the vehicle is around 18 square feet. The claim is that the top speed is 120 mph, which is the same as 176 feet/second. We can simply calculate the total aerodynamic drag from this information (and the average density of air (around one slug mass per 420 cubic feet). It is 0.3 * 18 * 1762 / 420 or around 398 pounds of aerodynamic drag. There is also tire drag which is around another 45 pounds for that vehicle weight. The total vehicle drag is therefore around 443 pounds (at that speed). If we just multiply this drag force by the velocity (176) and divide by 550 to convert it to horsepower, we get 142 actual horsepower as being needed. Given that they indicate that their motor efficiency is around 85% to 90%, and there are mechanical efficiencies of the tires and wheels, this is in fairly good agreement with the roughly 180 horsepower claimed available from their graph at 13,000 rpm (times that efficiency factor). This confirms that the expected top speed is likely to be around what they claim. Fine here.
Let's look at their acceleration claim, of zero-to-sixty in around four seconds (which is impressively fast).
They certainly did that demonstration in what they call first gear, which has a total gear ratio (and therefore torque multiplication) of 14.3. It is easy to see from this ratio that the motor would be turning at close to its maximum revs at 60 mph, so first gear might have been provided simply to be able to show off with this impressive zero-to-sixty acceleration. In any case, they provide a torque curve for their motor, which suggests that it would produce an average of around 160 ft-lbs of torque through this whole sequence. Multiplying this by the total gear ratio gives around 2300 ft-lb of torque, which becomes around 1900 pounds of thrust after considering the various mechanical losses. We have the aerodynamic drag of around 40 pounds average and the tire drag of another 40 pounds to subtract, so we have around 1820 net pounds of thrust available for acceleration. We divide this by the vehicle weight of 2500 pounds to get 0.73 to get the g-force acceleration. This is roughly 16 mph/second acceleration, or around four seconds to get from zero to sixty. This confirms that in their first gear, the acceleration they describe is realistic.
There is actually another factor involved here, regarding a flywheel effect of the motor rotor itself having to accelerate as well. Without knowing the Rotational Inertia (I) of that armature and rotor, it is not possible to calculate the reduction which must occur in this vehicle acceleration, but it must certainly be slightly less than calculated above. In other words, slightly over 4 seconds for zero-to-sixty is then realistic.
The acceleration claim also tells us something else about the Tesla! It has absolutely nothing to do with the matters at hand here, but it still seems worth noting. The acceleration they describe, of zero-to-sixty-in-around-four-seconds, means that the average acceleration is therefore around 0.73G (as indicated above.) On a dry and clean roadway, the best static coefficient of friction is around 1.0. This means that the 1820 pounds of thrust for acceleration must necessarily require roughly that amount of weight on the driving wheels, or around 1800 pounds. If one axle of a 2,500 pound car has 1,800 pounds on it, the other axle has only 700 pounds. This would be an incredibly dangerous vehicle to drive on any curvy roads, if it has that extreme of a weight-distribution. For an actual Licensed highway vehicle, it could not possibly pass road safety tests with such an extreme weight-distribution. Maybe it will be modified before any get onto the road. Which also would mean that the acceleration performance would necessarily have to be slightly less. (It is interesting all the things that Physics can tell us about any mechanism!) (They might also have used extremely sticky tires for such runs, where less vehicle weight would then have to be on the driving axle.)
So the actual mechanical performance of their car is impressive. Again, much of that is because it is a rather small car that is very aerodynamic. Still, impressive.
However, when we get to the charging of the batteries, their claims seem extremely outrageous. They claim that after driving 100 miles (presumably at highway speed) it only takes two hours to recharge the batteries, and by simply plugging it in.
If we do a drag analysis for 60 mph (similar to the 120 mph calculations shown above), we can see that the total vehicle drag is around 100 pounds aero plus 45 pounds tires or 145 pounds total. As above, this calculates to 23 horsepower being constantly needed. To drive 100 miles at that (constant) speed takes 1.66 hours, or 38.7 horsepower-hours of energy. This is the same as around 29 kilowatt-hours of energy. However, getting electricity out of batteries is not a perfectly efficient process, and they acknowledge that their motor ranges from 90% to 80% efficient. To charge this amount in a two hour period therefore requires charging at a rate of over 15,000 watts. Their charger circuits cannot have perfect efficiency so certainly around 18,000 watts of household electricity would be needed.
If this were simply "plugged in" to a standard outlet, it would require 160 amperes at 110 volts! But standard household outlets are only rated at 15 amperes and even heavy duty ones are only rated at 20 amperes! They are talking about so much electricity that at least 6 or 8 standard outlets would be needed to provide enough power! In fact, the very special wiring that was put in your house for your central air conditioner might not be enough to provide the 80 amperes at 220 volts that would apparently be needed to charge a Tesla in the two hours as described.
In this area, their promotion is extremely misleading. It cannot simply be plugged in as they imply. Very heavy duty special house wiring is required to be able to do that massive charging.
From generally known evidence regarding charging batteries extremely fast like that, the internal structure of the battery often suffers and the battery lifetime might therefore suffer. They don't mention what the cost of replacing their battery pack is, but it certainly would be expensive. A moderately similar experimental electric car recently shown to the press has such an exotic battery pack that replacing it would cost over $300,000! Obviously, the Tesla battery pack is not that exotic or expensive, but it clearly would be a significant expense if and when it needs to be replaced.
A Tesla spokesperson was on TV talking about this after the above text was written. The battery pack would apparently currently cost around $9,000 to replace, but she pointed out that battery technology is constantly improving and that cost might drop. She also said that the battery pack lifetime is currently at least two years. It was refreshing to see an honest and open answer to such a question.
Similarly, as discussed much earlier about battery-powered vehicles, the COST of that electricity can be significant. Using Tesla's numbers and this analysis, we are talking about needing to charge around 29 kWh actually into the batteries (in those two hours, after that 100-mile drive). And that due to the efficiencies of chargers, this necessarily requires at least 35 kWh of actual house electricity. If electricity is charged at conventional rates of around 10 cents per kWh, this is around $3.50 for the electricity for that hundred miles. Granted that this is less than the cost of gasoline in any vehicle to go that distance, but it is still considerably more (around triple) what they claim the electricity cost would be.
But finally, the worst part of such an interesting vehicle is that problem described above regarding the amount of coal that would need to be burned at that remote electric powerplant to provide that much electricity. With the Tesla numbers and this 100 mile trip example, the calculations presented far above show that around 65 pounds of coal would have to be burned in that unseen electric powerplant, which would send around 240 pounds of carbon dioxide into the atmosphere, to provide the electricity for a Tesla to make that (relatively constant speed) 100 mile trip. If a small gasoline engine were used instead inside a similarly aerodynamic and light and small vehicle, maybe two gallons of gasoline would have been required to go that 100 miles, which would have released around 36 pounds of carbon dioxide into the atmosphere. Even if a full-sized sports car such as one of my Corvettes made the trip, with there highway 27 mpg, only 3.7 gallons of gasoline would be used, which would send 67 pounds of CO2 into the atmosphere. The Tesla causes nearly four times as much carbon dioxide to be dumped into the atmosphere than my big-gasoline-engined Corvette would!
Therefore, the Tesla, which is being promoted as being TOTALLY green, in reality causes at least four times as much carbon dioxide to be sent into the atmosphere than if it simply had a gasoline engine in it! Otherwise, it seems to be a rather attractive idea! Impressive acceleration and top speed and decent range. Only the immensity of the charging process, and the consequences of that are such terrible necessary requirements. Like discussed above, NO battery-powered vehicle has any of its own energy, and it requires to get all that energy from some different power source, in this case, house electricity. Even if Tesla is right that electric power companies would give tremendous rate reductions for the electricity because it was nearly all used at night, that cannot stop the requirement that the (remote) electric powerplant necessarily has to cause the release of that 240 pounds of carbon dioxide into the atmosphere from the coal burned.
By the way, many of the advantages of the Tesla have to do with its tiny size and very aerodynamic shape. Any car that had a more conventional size and shape would require a far, far bigger motor and far, far more electricity and battery size and capacity. If that car had a similar horsepower gasoline engine in it, the acceleration and top speed would be comparable, and the gas mileage would be impressive. The two main differences would be that the range would be easily 500 miles (with maybe an 8 gallon gas tank) and that the weight of the vehicle would be more engine instead of the same total weight of batteries.
The Tesla information is very vague about its battery system. Obviously, they are protective about their own unique advances. But we have calculated here that to charge at the rate they describe, there must be around 15,000 watts of charging that is done. Their literature mentions that their charger works at 70 amperes. This seems to imply that their batteries must be a series battery pack, because these numbers imply an effective battery voltage of around 200 volts. Such a high voltage (instead of conventional cars 12-volt batteries) makes a lot of sense in permitting far thinner wires to be used inside the car and in the charger and connectors, although even 70 amperes requires fairly stout wiring.
I suspect that you will NEVER see any reference to a Tesla being driven at night (because all those light bulbs use up a LOT of electrical power which is therefore taken away from being available for the electric motor); nor being driven with the (included) air conditioning operating. Automotive air conditioning normally takes around 6 horsepower, so the 23 required horsepower for that 60 mph highway driving would become 29 horsepower. This would both reduce the range by 25% and increase the charging time by 30% (as well as increasing the carbon dioxide given off at that distant electric powerplant by another 30%).
I realize that there are many optimistic people who simply say that the detriment of burning coal (which currently provides around 51% of all the electricity used in the US) could be eliminated by CHOOSING to use nuclear powered powerplant electricity instead. First, you don't have any way of deciding where your electricity is made, but second, few people seem to realize that the US already mined essentially all of its Uranium some years ago, and all of the 39 Uranium mines in the US have been closed and completely shut down for some years as a result. We import virtually all the Uranium used in American powerplants! No one seems to know that! (Only a very small percentage is actually from US sources, and that happens to be from the decommissioning of nuclear weapons, for just a few percent.)
There are certainly other even more optimistic people who simply assume that photovoltaic cells (solar cells or PV) can supply the needed electricity. First, such electricity is only available during the daytime when the sun is shining (and Tesla describes recharging through the night). But people who want to believe that have no clue as to how many PV cells would be needed! We have calculated above that around 18,000 watts of electricity would be needed to do the charging that Tesla describes. In a different energy-related page in this Domain, we present the Physics of PV devices, where around 7 watts per square foot of PV cells is possible during bright sunlight around noon. Even under those perfect conditions (noon, no clouds) around 2600 square feet of PV cells would be required. That web-page presentation describes that it is common that around $150 in total installed cost is involved for each square foot of PV cells. This would mean that around $390,000 worth of solar cell installation would likely be required to provide the amount of electricity the Tesla describes being needed! I suppose that if you can afford a $92,000 electric car, you may also be able to afford $390,000 of solar cells to charge it! But keep in mind that this is for NO CLOUDS and only around noon! Even more solar cells would be required for nearly any real climate!
See the problems? Even though that Tesla can show impressive acceleration and top speed, and decent range, and even though it is such a tiny car that the amount of electricity used is only around three cents per mile (while even at 50 mpg with a small gasoline engine, the gasoline would currently cost around 6 cents per mile), the bottom line regarding why it is even supposed to be desirable is allegedly how GREEN it is. But the reality is that some distant electric powerplant has to pump at least four times as much carbon dioxide into the atmosphere than if the vehicle had simply had a smaller gasoline engine.
The single point for which it is sold is therefore (sadly) totally invalid. It may be fortunate that the only people who will be able to buy a $92,000 car probably have plenty of money available! However, I suppose that most of them will not even be bothered by the need for maybe an extra thousand dollars of specialized heavy duty wiring being installed in their house to be able to charge the Tesla. And their likely lifestyles are such that they will never even notice if their electric bills happen to get a lot higher because of charging their Tesla.
I see it as a wonderful "novelty" for rich people to play with. For the practical reasons presented in this article, it seems inconceivable that "normal" people will ever benefit from such battery-powered vehicles or even use them (except for golf carts and electric wheelchairs).
It would be nice to be able to say that there was any chance whatever that this technology could advance to actually becoming useful some day. But Tesla even notes that they have already accomplished impressive efficiencies of around 90% and 80% at peak use. What a Tesla has is probably about as good as it will ever be able to get. And if it were not for the horrible requirement that some distant electric powerplant has to release massive amounts of carbon dioxide into the atmosphere to be able to charge the Tesla, it actually could be a useful product. But when a product is SOLD and PROMOTED as being totally green, while the actual reality is entirely opposite, it then turns out to be a really terrible idea!
The truly sad thing is that if millions of people could some day drive vehicles that are electric powered like the Tesla, Global Warming would necessary become far worse as a direct result.?
Such limitations have led to an enormous interest in alternative power sources, of which the fuel cell is the most promising candidate. Storage density, i.e. the electrical capacity available per unit mass of energy storage means, is one of the most important parameters.
So you have the well-known battery and competing fuel shills who are anti-hydrogen sheep:
Ulf Bossel of the European Fuel Cell Forum,
Alec Brooks
James Woolsey
EV World
Sam Thurber
Cal Cars
Felix Kramer
Yet for every manipulated argument they come up with, they are shot down by hundreds of sites with facts.
The interventions of these 'doubters' fall into a number of clear categories which I'll summarise as:
1 "You can't succeed because no-one has ever succeeded at this (sports car making / battery-power / taking on the majors, etc etc) before". - May I commend to everyone Dava Sobel's wonderful (and short!) book, "Longitude", which offers a perfect map of the tendency of government and the scientific establishment collude to reject true innovation. This effect can only be overcome when a tipping-point of perceived popular utility is reached, at which point the establishment suddenly has a bout of collective amnesia about their earlier denials. (Same story many times over, historically, of course - from Gallileo onwards.)
2 "It's inefficient to carry around". Rather as it's inefficient to carry around a full tank of gas, perhaps? Or to carry around a SUV chassis which itself weighs a ton or more? (Come on, Detroit, you can find a better argument than that, surely?)
So let's be vigilant for any who claim, in a smooth way, that invention can't possibly have the answers. From a position of some expertise in this field, may I remind readers that the "you-don't-understand-how-our-industry-works" argument has been the policy instrument of choice for numerous corporate fraudsters and protectionists down the ages (Enron, anyone?). New York's energetic DA, Mr Spitzer, has made a fine career out of challenging such thinking in the finance sector (with the simple rejoinder: "WHY does your industry work like that? Against customer choice?"). And then of course there's the entire consumer movement (remember Flaming Fords? remember "Unsafe at Any Speed"?). We can and should ask the same questions of the conventional auto industry.
The good news is that genuine innovation will out - as long as ordinary consumers are able to find it and buy it. One of the early lessons of the twentyfirst century, thank goodness, is that the old-school, browbeating style of corporate communication - terrorising one's customers into rejecting alternatives - increasingly fails as people wise up to making decisions based on their own independently-gathered information about benefits and risks. (Interestingly, a popular reaction against "selling by fear" is also now happening in the political field. Now why might that be?) As a consumer, one doesn't have to agree with the in-ya-face techniques of anticorporate critics like Michael Moore and Morgan Spurlock to still subscribe to the view that we can buy what we want to buy. We no longer want to be told by old-tech that new-tech is inherently suspect. Isn't it old-tech that brought us dependency on oil, climate change, wars over energy sources?
So c'mon people, how about a reward system for "spot the spoiler"? I'm all for free debate on the issues, but some of these blogs smell rather like the work of paid old-tech corporatists trying to sabotage your success.
Challenge such interventions with the greatest possible vigour, and let consumers decide for themselves!
1.) Battery companies are spending millions of dollars to knock H2
because it works longer, better, faster and cheaper than batteries! Most of the people writing these screaming anti-H2 articles are battery company shills or have investments there. H2 does beat batteries on every front so the should be SCARED!
2.) The steel unions hate H2 because H2 cars don't use steel. Steel is
too hard to afford any more so nobody will use it in any case.
3.) Activists hate H2 because they think it can only be made by the oil
companies and they hate the oil companies. This is a falsehood created by the battery and steel guys.
4.) Oil companies hate H2 because it is so much better than oil but they
only get to hate it unto 2030 when the affordable oil runs out. Then they know they must love it because H2 energy will be all that is left. The Oil industry is dismayed that H2 is coming on so fast and they are trying to slow it down even more.
5.) Other alternative energy interests hate it because it is getting all
of the funding because the polita-nomics are better with H2 than ANYTHING ELSE ON EARTH.
If the gasoline in your car blows up it will do a VAST AMOUNT more death and damage than H2 ever will. You are driving a MOLOTOV COCKTAIL. In 2030 oil is GONE and there is NO OTHER OPTION that can be delivered world-wide in time but H2! Biofuel only solves 2% of the problem. Batteries have failed. Nuclear is too dangerous.?
Some math errors, though.
As you point out, it takes a lot of coal burned in a central power plant to deliver enough energy to a home to equal the energy content in a gallon of gas-- 60 pounds, according to your numbers.
But then you go on to say that charging an electric car would require supplying (from a home electric outlet) the equivalent of the energy in 60 pounds of coal! So you're penalizing the electric car twice for all the inefficiencies of utility power distribution.
Since those inefficiencies are high, your estimated net cost of $3.20 per gallon equivalent is many times too high-- the real number is well under a dollar.
You also talk about the electric load for recharging batteries in the home, but you pretend that generating the same energy value in the form hydrogen, again in the home, is no big deal. There's no free lunch here. Whether by electrolysis or frickin' laser beams, splitting the hydrogen out of water takes energy. And although you mention microbial decomposition, that's a low power-density process, so it would take a huge volume of microbes to get the job done. Home users aren't going to install 10,000-gallon chemical reactor tanks.
You also made some bad estimates of the drag on the Tesla during the 0-60 mph and highway cruise analyses. You used the tire drag figures from the 120 mph case, and you apparently used a linear interpolation to generate the aerodynamic drag for these lower speeds from the high-speed numbers. In fact, aero drag is not linear with speed. The effect of aero drag on 0-60 acceleration is pretty much nil, and the total drag on a Tesla roadster at 60 mph is probably half what you say.
You didn't count the carbon overhead for refining the gasoline for your Corvette, your supposition that the Tesla's electric lights will effectively preclude night-time driving was ludicrous, and your general tone was... a bit over the top, let's say.
But I agree that hydrogen fuel cells may yet play some role in our energy economy.
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