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.
My buddy Michael Kanellos wrote a CNET article (here) about a portable fuel-cell power supply from Trulite.
Kanellos made a small error in his article (or Trulite did when they briefed him), describing the device as using a chemical reaction involving "sodium hydride" to extract hydrogen from water.
That surprised me, since sodium hydride is extremely caustic (it's a base, the opposite of an acid), strong enough to be dangerous if exposed to air or water.
Well, not to worry. According to the company's website (here), the chemical is actually sodium borohydride, a safer compound.
That put me back onto familiar ground, since Medis Technologies, another company developing fuel-cell products for consumer and commercial applications, also uses sodium borohydride, and I've looked into that company's technology before. In both systems, the hydrolysis of sodium borohydride releases pure hydrogen, which is run through a fuel cell. The hydrogen reacts with oxygen from the air, producing power and water.
Sodium borohydride is safer than sodium hydride, as I said; it's also generally safer than gasoline, which is the most common fuel in the small generators that these fuel-cell systems are designed to replace. But it's only relatively safe; it's still what most people would call a hazardous chemical. An MSDS (material safety data sheet) for sodium borohydride (here) says:
DANGER! CORROSIVE. CAUSES BURNS TO ANY AREA OF CONTACT. HARMFUL IF SWALLOWED, INHALED OR ABSORBED THROUGH SKIN. FLAMMABLE SOLID. DANGEROUS WHEN WET.
So for safety reasons, when sodium borohydride is used in consumer products, it must be provided in some kind of sealed canister, which probably receives the waste from the process. If not, there must be another canister involved, since there's definitely some waste to deal with.
Trulite and Medis don't talk about the waste produced in their systems; ordinarily it stays sealed up in its canister so users don't have to worry about it. But I did a little research, and it looks like the waste is sodium metaborate tetrahydrate, a relative of good old borax, the stuff Ronald Reagan used to advertise on TV (like here). It isn't very dangerous, but users will still need to be careful about these canisters, in part because the original sodium borohydride may not be completely consumed when the fuel cell can no longer generate useful amounts of power.
I suggest that users should check with their local garbage companies to see if they're allowed to discard these canisters in household trash. (And of course you know most garbage companies are going to reply with a immediate "no!"; it may take months to get a more carefully considered response.)
It seems to me that Trulite and Medis want people to focus on the fuel cell part of the product because fuel cells are thought of as very "green"-- to the extent consumers know anything about fuel cells, they probably know the traditional refrain that "fuel cells emit only water."
But with these things, the result is water plus a canister full of gunk you won't want in the house and can't throw in the trash. That is not so green.
My other objection to sodium borohydride-based fuel cells is that they're not very efficient over the total cycle. Sodium borohydride has to be manufactured, and the manufacturing process takes a lot more energy than the user will ever get out of the fuel cell. Then there's the canister itself, and the costs of shipping the canisters around.
The Trulite KH4 described in Kanellos's article weighs 20 pounds and generates not more than 200 watts of power. The company's website doesn't talk much about the energy capacity of the system, but a December 2005 SEC filing (here) says the KH4 (apparently that stands for Kitty Hawk 4) can produce 100 watts for 4 hours. (I should note that the KH4 may have been substantially improved since then, but since the company isn't saying, I have to go with the information I can get.) That's as much energy as eight average laptop batteries-- a significant amount-- but charging those batteries would cost the user about a dime. Trulite's replaceable Hydrocell canisters surely must cost at least 100 times that much. (And I wouldn't be surprised to hear they cost 1,000 times that much, given the high price of the KH4.)
The Medis 24-7 Power Pack, just now coming to market, is a 6.5-ounce cellphone-size gizmo that produces 20 watt-hours of energy and costs about $30. That's about the size, weight, cost, and energy capacity of 8 AA NiMH batteries, but those batteries can be recharged hundreds of times. When the Medis device runs out of energy, it has to be thrown away.
If these devices become popular, manufacturing costs will come down, and so will retail prices, presumably. But for now, you'd have to have a really extraordinary reason to want one.
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