Portable energy sources.

[Frank]

While batteries have come a long way, their energy density is still puny. They're mostly as useful as they are, because the equipment they supply needs less power to operate. And we might want to power things that require much more energy than that.

Things like plain generators are big and noisy, nucleair power that size is a pain to develop. And while things like fuel cells show promise, they still haven't delivered. What do you think would be the best one?

 

[Fodder]

I don't know about being the best choice, but I found mini jet turbines to at least be an interesting idea.

 

[nelg]

I think we could easily double [the energy capacity of] what we have right now. We have cells in the lab that, if you run the numbers for a thin-film cell of reasonable size, you end up with two to three times current lithium ion [batteries].

But there's more. The fantasy of all fantasies is chromium. If we could stabilize chromium [as a material for battery cathodes] and I could...give you a battery with 600–700 watts per kilogram [of energy capacity] with reasonable drain rate, that says good-bye hydrogen economy.

 

[Basic]

I refuse to give any credit to anyone who use Watt as a unit for energy.

 

[3dcgi]

I wondering how efficient thermoelectric generators like Thermo Life will get. Currently it gets 3V from the difference between body temperature and the air.
http://www.poweredbythermolife.com/

Now if only someone can figure out how to turn heat into electricity without needed to maintain a temperature difference. Then it will be easy to recycle heat from our CPUs and GPUs. High current generation and thus power output would be nice too.

 

[K.I.L.E.R]

Or those who use Kg/pounds for weight.

I refuse to give any credit to anyone who use Watt as a unit for energy.

 

[Frank]

Intresting developments!

Does anyone know what the problem / gain is with chromium?

 

[Guden Oden]

I wondering how efficient thermoelectric generators like Thermo Life will get. Currently it gets 3V from the difference between body temperature and the air.

3V while doing what? Voltage isn't a measurement for power output, it's just that; voltage. Like, static pressure in a closed water tap. What happens to the voltage once you put a drain to it?

Now if only someone can figure out how to turn heat into electricity without needed to maintain a temperature difference. Then it will be easy to recycle heat from our CPUs and GPUs. High current generation and thus power output would be nice too.

Um, that's perpetual motion, and physically impossible. There must be a difference for any energy to be extracted. Like, you can't run a hydroelectric generator plant just by immersing it into a lake and expect the water to run around in the turbines on its own, you must have elevation, so that gravity drives the water downwards so electricity can be extracted from the motion energy.

 

[Bigus Dickus]

Or those who use Kg/pounds for weight.

pound is a weight

 

[K.I.L.E.R]

pound is a weight

No it's Newtons.

 

[Guden Oden]

Um, newtons is force last time I checked... Kilos etc is weight.

 

[K.I.L.E.R]

Last time I checked gravity was a vector force.
My physics teacher gave me a big cross for measuring weight in mass rather than Newtons.
I don't know about you yanks but down here in Australia we use SI units and we measure weight in Newtons and not mass units.

Um, newtons is force last time I checked... Kilos etc is weight.

 

[Guden Oden]

I don't know about you yanks but down here in Australia we use SI units and we measure weight in Newtons and not mass units.

"You yanks"...

Dude, look. I know you eat coffee grounds and I won't make any big deal out of it, but newton is clearly an unit of force. You can check this yourself at many places on the web, http://physics.nist.gov/cuu/Units/units.html for example.

 

[Frank]

Kiler is right: mass is measured in kilograms/pounds/whatever, while weight (the force that pulls that mass down) is definitely measured in Newtons.

A mass of 1 KG will still be that on the Moon, but the weight will be about a sixth of the 9.81 Newtons it weights on Earth.

 

[nutball]

The confusion arises I think because of the way many people weigh things ... if you use balance scales for example and stick your bag of carrots on one end and a 1 kilogram reference mass on the other then the "carrots weigh 1 kilogram". Well no they don't, they have the same weight as a 1 kilogram reference mass. Because the gravitational constant cancels out on both sides of the equation it gets ignored.

 

[Xmas]

DiGuru, a mass of 1 KelvinGiga?

 

[Frank]

DiGuru, a mass of 1 KelvinGiga?

What about a mass of 1 Giga electron volt?

 

[DudeMiester]

afaik

10^9 eV=m*c^2
m=1.7826617280267879498514335636017 x 10^-27 Kg

 

[3dcgi]

3V while doing what? Voltage isn't a measurement for power output, it's just that; voltage. Like, static pressure in a closed water tap. What happens to the voltage once you put a drain to it?

I'm no expert on their technology, but they claim the generator can power small portable devices like sensors, medical devices, and zigbee wireless chipsets.

Um, that's perpetual motion, and physically impossible. There must be a difference for any energy to be extracted. Like, you can't run a hydroelectric generator plant just by immersing it into a lake and expect the water to run around in the turbines on its own, you must have elevation, so that gravity drives the water downwards so electricity can be extracted from the motion energy.

My post was a little tongue in cheek yet I still disagree. Perpetual motion is renewable energy with perfect efficiency. There are a lot of ways to recycle energy without being perpetual motion. At one time it probably seemed like magic to create electricity from sunlight yet we do it.

 

[CosmoKramer]

Um, newtons is force last time I checked... Kilos etc is weight.

Kiler is right. In physics/mechanics we distinguish between mass and weight.

Weight is a force, forces are measured in Newton.

Kilos is not weight. Kilos is a measurement of mass.

Sounds weird? The trick is to realize that your mass is (approximately) constant, i e my mass is 90 kg regardless if I walk on earth or the surface of the moon. Of course, the different gravity fields will cause my weight on the moon to be 1/6th of my earthly weight.

Edit: Nevermind, I responded without reading that several people already pointed out the same thing.