Congratulations on maintaining a "must read" blog! You provide a consistently high level of analysis and hard-nosed "out of the box (rut)" problem solutions not rivaled elsewhere. With an engineering and science background myself, I admire your breadth of expertise. Keep up the good work; I wish you had time to do more.
OK E-P. I want to know why, if Zinc-air batteries are so cool, noone is building them for vehicle applications anymore and why all the published research materials on Zn-Air are no more recent than about 1999? If zinc is the miracle metal, why doesn't anybody else think so?
This is a very serious question. There are a lot of promise to Zn-air batteries, and you've done a great job showing that (I'm convinced). However, I can't help but be skeptical and think that there's got to be a catch they we haven't discovered yet. Otherwise, there would at least be a few folks out there on the fringe publishing research on it. After 1999, the only info I can find on Zn-air is on its applications for the military - providing long-lasting batteries for eletronics for soldiers in the field - nothing on vehicle applications.
Darn, do I ever wish I knew the answer to that. I'm not sure why Electric Fuel hasn't posted any results since November '04; you'd think that they'd be pushing forward with support from someone somewhere (especially given the dual push for engine cleanup and CO2 reduction across Europe), but if they have anything it's not on the site.
The slurry-refillable cells that LLNL was developing are another matter. They gave an exclusive license to Power Air Corporation, a very secretive company which did not even have a website. I'm not a big fan of conspiracy theories, but it looked an awful lot like that technology had been deliberately buried.
That picture has changed. I did another search, and they've got a much bigger web presence (as well as a new name). No announcements of actual products yet besides this OEM demo module, but lots of companies play things close to the vest for good or ill.
FWIW, it looks like you could get some serious range out of those OEM cells; at 10 kWh each, six would weigh about 500 pounds but drive a Prius+ well over 200 miles. You'd need something else to handle surge power requirements and regeneration, but it looks great for a ZEV city car. Ford should put a bunch of them into an Escape taxi.
I think I can support anyone who can think hard about problems and propose solutions backed by numbers. That's what I come here for. Thanks very much for doing it. There's not too many of you out there.
Want to know something funny? The resources on the Web these days will let anyone do what I'm doing. I'm nothing special; I've got some physics, chemistry, math and the other stuff that comes from your every-day engineering degree; you can literally learn this at the library if you want to. I have no advanced degrees, no training in research. All I do is connect things together and point out where stuff doesn't fit, which anyone can do.
The problem is that so few people do it. I'm trying to lead by example.
I had no idea all this stuff was out there when I started two years ago, but it is and I'm trying to get the word out. I'm hoping that this will lead to poor ideas being analyzed more widely and rejected more often.
First, let me congratulate E-P on two years of superb writing. This is a great blog because of how much attention you pay to detail. If more people thought like you did, perhaps the future of energy would be a little different.
While the floor is open, I'd like to get something off my chest. I've been reading peak oil material on the web for over a year now, and quite frankly I'm getting really sick and tired of the 'fatalists' popping up everywhere.
As far as they are concerned, peak oil is going to send the world into armaggeddon as we all scrap for the last resources. The price will rise to such an extent that our way of life takes steps back to third-world standards. Clean water will become a distant memory, and our standard of living will drop to previously unseen levels. And the worst part... according to them, there's nothing anyone can do about it. According to these people, renewable energy is a non-event because we still need oil to produce so many products used a lot today. A recent contingency report here in New Zealand showed that over 50% of our oil use came from private vehicles, so I'd suggest renewable energy IS actually an event. But that news is kept silent because good news is no good do a doomsayer.
I really think this is all about power. People with this attitude like the idea of somehow sounding more knowledgable than the rest of the 'common public' and like to try and scare them. Perhaps in a way, they have a certain degree of hope that it WILL happen, for the sole reason that they can sit back as the world collapses around them and they get to say "I told you so".
This negativity will solve nothing. If people believe we can solve the problem, then we can. The mind has the power to accomplish a lot.
On those zinc-air batteries would it make sense to use them in a CHP (combined heat power) unit to buffer or balance the heat verses power needs or even shut down the unit during off peak times when the avoided cost of power is low in a net metering situation? Or in a Wind or Solar application would there be any benefit.
The throughput efficiency of zinc-air is roughly 50%, which is not something you'd want to use for most RE applications. The advantage is high energy/weight, external regeneration of metal (you can refill in minutes instead of recharging over hours, though the new Li-ion formulations are chewing into that advantage) and several different ways of regenerating metal (chemical or electric).
The self-discharge rate of zinc-air can also be reduced to zero by sealing the battery against oxygen. This is great for standby operation, but not so important for RE where you're cycling every day.