New Method To Generate Electricity from Water

spaceling writes "The BBC reports reporting on research published in the Institute of Physics Journal of Micromechanics and Microengineering of the first new method of generating electricity in over 150 years. Larry Kostiuk and Daniel Kwok 'created a glass block, two centimetres in diameter and three millimetres thick, containing about 400,000 to 500,000 individual channels...[and] generated about 10 volts with a current of around a milliamp. This allowed the team to successfully power a lightbulb.'" This has also been covered all over the place.

Comments

Liquid flow...

[Webtommy88]

From the article:

While scientists have realized for decades that a flowing liquid could separate electron charges, no one appears to have linked the effect with a way of generating electricity.

So... if these things end up becoming cell phone batteries and what not, where are you going to get the water flow needed to separate the charges?

Shaking the phone or something? That just looks dumb :^)

Re:Liquid flow...

[Anonymous Coward]

So now the bitch in the Volvo putting on eyeliner and talking on the phone will have something else to distract her as she runs me off the road.

Of course, it's not going to be valid...

[PatrickThomson]

In the humble opinion of the battery manufacturers

A hype?

[hankwang]

This story looks like it's hyped. The device converts a flow of particles caused by a pressure difference into an electrical current. The paper itself (PDF, you probably need to be a subscriber, but the abstract should be accessible for everyone) shows efficiencies between 0.0001 and 0.04. The higher number is only obtained if the external load is matched to the device within a factor 10, i.e., the device looses the pressure difference if you don't use the current.

If we take one liter (1 kg) of water at a pressure of 30 cm, then the energy contained is 2.94 J, of which 0.12 J will be available as electrical output. By comparison, a 1500 mAh NiMH battery can store 6500 J. The efficiency of the water battery can probably be improved, but let's face it, for small volumes and reasonable pressures, the stored energy density will never be very high.

Re:A hype?

[GospelHead821]

According to the paper, itself, they seem to be interested more in powering MEMS. I can imagine many situations in which a chip designed to analyze a fluid wouldn't require a battery because the chip's sensors will be powered by electricity generated as the pressurized fluid traverses an "electrokinetic microchannel battery" at the front end of the chip. If they can increase the efficiency and insure that a thumb-operated pump (like the primer on your lawnmower) would provide sufficient pressure to drive the battery, this could be a really useful innovation.

Sounds like a van der Graaf

[panurge]

In fact, I've seen van der Graafs that work by using a flow of dielectric fluid rather than the rubber belt of the school versions. Admittedly they generate megavolts rather than volts - but isn't the basic method the same? i.e. charge separation.

Also, the electricity isn't generated from the water. It's generated using the kinetic energy of flowing water - just like a turbine or waterwheel, and something needs to produce the kinetic energy in the first place...excuse me while I go and check my cold fusion plant, the room temperature seems a bit low.

Re:Sounds like a van der Graaf

[Anonymous Coward]

Your room is cold because cold fusion doesn't generate heat, but uses it up. That's why it's called cold fusion.

With normal fusion you can simply use the heat to boil water and send the steam trough a turbine, which will turn a generator; with cold fusion you need to put the reactor in a high place and use it to turn air into liquid, which will then fall down and turn the turbine like a watermill. You can then let the liquid air to either reheat and boil away, or sell it for a profit.

Obviously, this power generation model will, when widely deployed, lower Earth's mean temperature. It is excepted to be one of the major players in a war against global warming.

Up untill recently, cold fusion was considered an unviable energy source (sink, actually), because (due to it's diametrically opposed nature to normal fusion) it requires extremely low pressures and/or cold temperatures to occur effectively. However, with recent breaktroughts with superconductors, cold fusion is now closer to a commercial application than it once was. Superconducters can be used to provide the cool neccessary for cold fusion because, after all, they are allways very cold.

Re:So now we end up fighting wars over water?

[Gorny]

There are lot of (more or less potential violent) wars over water. Turkey has build waterpowered electricity plants which use so much water that other surrounding countries saw their waterlevels drop. There are more examples besides this one from the Tigris: http://news.bbc.co.uk/1/hi/world/europe/943002.stm

Yes.. I think it's entirely possible to have real wars in the future not to establisch democracy in a country, or to expand the territory of the aggressor but entirely focussed on the water.

Re:generating electricity

[EricTheRed]

True except that Nuclear Reactors don't generate electricity directly - they do so by converting water into steam which powers turbines, and the base technology for that is 150years old or so.

Re:Laws of thermo-dynamics

[BillFarber]

The energy comes from the water pressure requiredd to force the water to flow through the channels.

Remote controls, watches, etc.

[Captain Kirk]

This produces a tiny amount of power but it could be ideal for things like TV remotes, wireless mice, garage door controls, etc.

Sure its being hyped a bit there is a lot of potential here.

Cool! (literally)

[xyote]

We'll be able to water cool and water power cpu's at the same time.

Heh! I noticed not a lot of RTFA in evidence. The researchers who discovered this stated where the energy comes from.

electricity generator != energy source

[JulianOolian]

It's a new method of generating electricity, not a new way of storing energy or an energy source. The energy would have to come from somewhere else, and since the idea is pretty new, I doubt that anyone knows in much detail how (or if) it will work out in practice.

I suppose you could either recharge a normal battery by pumping the handle your handy, portable water-generator for a few minutes, a bit like a baygen radio.

Or, you could store the water under pressure and let it out through the device to get the energy back out.

Re:So now we end up fighting wars over water?

[Spy Hunter]

The article title is misleading. This appears to be a new way to generate electricity from a pressure difference, using water flowing through small channels. It is not a method of generating electricity "from water," it is a method of generating electricity with water. The BBC article is guilty too, they misleadingly call it a "power source" when it is clearly a power storage technology (unless you have pre-pressurized water, maybe from geothermal activity or something). These few sentences from the article reveal the true nature of this discovery:

What Professor Kostiuk and his team have achieved is create a kind of turbine device that does not have moving parts. "Efficiency is a fraction of 1% and right now we are trying to fully understand the characteristics of such devices. The real goal is to find ways of improving its efficiency to around four to 16% to compete with other energy sources."

Re:So now we end up fighting wars over water?

[orthogonal]

Iraq is blessed with an abundant supply of water, so much so in fact that some had speculated we did not go there for the oil as much as the water.

Who in hell speculated we went to Iraq for their water??

The Fremen High Council?

Are the Bene Gesserit speculating we went there for the Spice or the Sandworms too?

THIS IS NOT A NEW WAY OF GENERATING ELECTRICITY!

[glomph]

See, for instance, http://www.amasci.com/emotor/kelvin.html

Which operates under a very similar principle, but with macrochannels. I built one of these when I was a kid, thirty-some years ago. It is so damn cool, your tongue sticks to it!

Re:So now we end up fighting wars over water?

[Dun Malg]

There are lot of (more or less potential violent) wars over water.

You make a very important point. Heck, look at how we fight over water in the US. We don't generally have "shootin' wars" over it anymore, but there's certainly a lot of acrimony. The various states arguing over how much water they can keep behind the dams and how much they can take out for irrigation on the Colorado river, for example. The California aqueduct taking most of the water in the Owens valley area and piping it down to Los Angeles caused a fair amount of strife too. I was driving around northern Nevada once about 10 years ago and I saw signs in store windows that said "Don't let Las Vegas take our water". Access to fresh water has been a central issue to civilization for eons. Heck, the first thing those monkey dudes in the beginning of "2001: A Space Oddessey" did after seeing the monolith and "gettin' wise" was grab bludgeons and chase off those other monkey dudes from the watering hole. Just a movie, but it makes an important point.

Personal electric generation.... My shoes!

[Wubby]

Why not put a couple pumps (no pun intended) in the soles of shoes? As I walk around I could generate the power I need to recharge my phone/low power laptop.

Hey, maybe it would force me to exercise more.

*ring ring*
ME: Hey... Bob... what's... up....[huff puff]
BOB: Dude, why are you outta breath?
ME: Phone... dying... needed... recharge...[cough]

Kids wanna play thier Gameboy... make 'em walk the dog! (hmm, mini paw sized pumps)

Re:Photoeclectric effect is not 150 years old

[michael_cain]

Correct. Discovery of the photoelectric effect is credited to Hertz in 1887, so it's less than 120 years old even if you use that discovery, rather than Einstein's explaining how it works.

Is this really anything new?

[guygee]

I read the actual paper, (available, with registration required, here), and granted, these guys did a good job on the analysis and experimental verfication, and also should be commended for bringing attention to this phonemena, but the basis for their work has been know for quite some time. In the field of geophysics, it has long been known that "spontaneous potential" exists due to the flow of water through sermipermable layers of rock and clay. A bibliography on spontaneous potential in boreholes has been compiled by the USGS with some papers dating back to the 1940's.

The real questions are how practical and economically viable this approach will be for medium to large-scale power generation. For natural sites (e.g. permeable rock layers), what type of electrodes can be used, how well will they resist corrosion, and how large must they be? The bottom line: how much will the power cost over the entire life cycle in terms of $ per KWH?

For manufactured microchannel membranes or devices, added questions are the cost of manufacture and the lifespan of the device. How easily will the pores become clogged, what steps must be taken to prevent this, how long will it take for the pores to erode over time, and what is the expected lifetime of the microchannel device?

One big difference between pure science and engineering is that engineers need to factor in economics.

There are much better ways

[poelzi]

I began recently to work on high frequency eletrolyse and magnetic electrolyse which hase a much better efficacy.
The Energie Problem is solved decades befor, but open your eys - Nobody can sell it without risking his life.

For example:

http://www.cheniere.org/books/excalibur/moray.ht m

From "FUEL FROM WATER, Energy Independence with Hydrogen" Author Michael A.Peavey Publisher Merit, Inc., P.O. Box 694 Louisville, KY 40205 Library of Congress Number 88-188956 ISBN 0-945516-04-5 Page 22.

" The smallest amount of energy needed to electrolyse one mole of water is 65.3 Wh at 25 degrees Celcius (77 degress F). When the Hydrogen and Oxygen are recombined into water during combustion 79.3 Wh of energy is released. 14 Wh more energy is released in burning Hydrogen and Oxygen than is required to split water. This excess must be absorbed from the surrounding media(environment) in the form of heat during electolysis." [...] "At 25 degrees celcius, for voltages of 1.23 to 1.47 V, the electrolysis reaction ABSORBS HEAT. At over 1.47 V at 25 degrees celcius, the reaction gives off heat."