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Batteries Powered by Leftover Food
Lazyhound writes "Technologists at the University of the West of England in Bristol have come up with a cheap, organic battery that can run on household leftovers, and be manufactured for just £10." There's also a New Scientist article. The New Scientist would like to point out that they broke the story, and the BBC followed up.
Why? We are exposed to harmful bacteria all the time, almost all of us have e.coli in our intestines. That is why we wash our hands after going to the bathroom. Or after hadeling raw hamburger or chicken. Just make sure people know that they will get a tummy ache if they eat the stuff.
As x approaches total apathy I couldn't care less.
Most strains of E. Coli are harmless in normal concentrations, and indeed live in your gut without causing any problems at all. Students at universities/colleges worldwide use it in concentrated culture all the time without any special precautions. Only E. Coli 10571 (iirc), a weird mutant strain, poses a food poisoning risk.
Bob
The article describes a microbial fuel cell that is totally different.
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
Scientists say 50 grammes of sugar would keep a 40-watt light bulb lit for eight hours.
.32 Killowatt Hours.
.06 here. So we're talking about 2 penny's worth of energy.
.02 cents.
Let's do the math. 50 grames = 12 1/2 servings. Or, 12.5 * 15 = 187.5 C (That's big C calories or really kilo-calories).
40 watts * 8 hours =
A KW Hours costs about
A round cylindrical sugar container of the coffee area variety has 567g's so were talking about 1/10 of a thing of sugar which costs about $.50.
So, the sugar costs 10 cents but the same energy produced by a power plant costs
So, when the greens step up the argument of, big business is squashing new alternative energy sources, maybe there's sound economic reasoning on the part of the neysayers.
50g sugar is about 5 cents.
50g gives 40 watts for 8 hours = 0,32 Wh. Where I live that's about 7 cents worth of electricity.
But the really interesting part is of course how it compares to conventional means of disposing garbage. And I'm pretty sure that 0,32 Wh of portable electricity is quite a lot better than the power output from burning 50g of sugar (or placing as part of a large smelly pile...)
The potato clock is just a battery, not a fuel cell. You stick two dissimilar metals into any electrolyte (such as the juice in a potato) and you get current. Heck, with one of those kits, you could stick the electrodes into your mouth and generate current.
On a related note, because the amalgam fillings in your mouth contain two dissimilar metals (silver and mercury), and saliva is an electrolyte, you could conceivably power your cell phone with your fillings. I am NOT making this up, there are documented medical cases where galvanic reactions involving amalgam fillings have been observed, e.g.: "Dr. William Cheshire, a physician at the Mayo Clinic, reports on a case where a woman's trigeminal neuralgia (tic douloureux) was traced to a galvanic reaction between an amalgam filling and an adjacent gold-alloy crown. Consumption of tomatoes and other acidic foods produced intense jolts described as being like those of an 'electrical battery'." (The abstract is here.
------ "Darn floor. Big bite." (Koko the gorilla's best attempt at explaining the experience of an earthquake.)
I also think it is a bit of stretch to say that this is a "weird mutant strain" since there are plenty other types of E. coli that can cause diarrhea via food poisoning (including the closing related Enteropathogenic E. coli. Incidentally, O157:H7 doesn't seem to hurt adult cattle too much, it just seems to have a really bad effect inside us (particularly children and elderly).
Brian.
Absolutely - ignorant media hype at work again. The pricks almost always get science wrong. The worst thing is that so many people fall for it.
The real reason that Escherichia Coli gets such bad press is a mere side effect of that it's such a common and incredibly populous inhabitant of a healthy human intestinal tract. That's what makes it such an excellent indicator of untreated sewage content.
When you're investigating possible sewage pollution, there's no point beginning with looking for the rare stuff that's dangerous in needle & haystack concentrations. No, you're better off counting the numbers of something that you're guaranteed to find, and extrapolating from there.
Of course, the media then jumps to the conclusion that, because a high E. Coli count probably means Really Bad Things are in the water, E. Coli itself becomes a Really Bad Thing.
Ahh - My eye!
The doctor said I'm not supposed to get Slashdot in it!
There has been a case recently in the UK of people running their Diesel cars off cooking oil thus saving 40p per litre. Police set up a 'frying squad' to sniff out cars which smelt like mobile chip shops, and local supermarkets rationed sales of cooking oil.
It's quite ingenious, though highly illegal...
"Information wants to be paid"
Actually, certian types of E. Coli bacterica live inside human intestine, as humans we have a mutualistic relationship with them. Without them, it would not be possible to extract nutrients from food we eat. The 'bad' type of E. Coli bacteria you're thinking of actually kills the beneficial bacteria in your intestines, and causes food to rot inside your digestive tract.
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