Engine On a Chip May Beat the Battery

Krishna Dagli writes, "MIT researchers are putting a tiny gas-turbine engine inside a silicon chip about the size of a quarter. The resulting device could run 10 times longer than a battery of the same weight, powering laptops, cell phones, radios, and other electronic devices." From the article: "All the parts work. We're now trying to get them all to work on the same day on the same lab bench." The goal is to do that by the end of the year.

Wow!

[Kirin Fenrir]

It's the energy source of the future! It's...

...gas?

Re:I wonder how safe they will be?

[allfunandgames]

Yeah really...I'd like to know where the gas tank will go. "Honey, I'm going down to the gas station to fill up my laptop!" :P

Small is not good for mechanical applications nece

[The Dalex]

That's a really interesting read (pancake analogy aside), although it sounds like the resulting device will be pretty fragile. A small grain of sand or a little dust buildup would cause complete failure. Large mechanical systems have the ability to power through minor problems like that, but such a small one will not really be suited for military field use, I imagine.

All parts work, just need to put it together

[140Mandak262Jamuna]

ha, ha ha. How many times the rookies in my dept have come to me excitedly and said, "Great news Boss, Got all the functions implemented and unit testing checked out ok. All I need to do is to put it together. Finished 90% of the code in just 10% of the time. Want to take a month off to chill out in Aruba!"

Then they spend 200% of the allotted time to make sure what they wrote in the first 10% interact with one another correctly.

p = mv & F =ma

[Anonymous Coward]

Since the mass of these materials is super small, the fact that they are moving at high velocity is no cause to hide under one's bed.

Also, at 20,000 rpm .. assuming that the "revolution" is a distance of 1 or 2 millimeters .. the ACTUAL velocity is nothing to send a letter home with.

Do the math (remember we are talking about the speed of the part of the object that is actually moving).

Another way of looking at it .. the total force cannot exceed the energy output of the gas expansion .. which is the result of a few micrograms of fuel.

pointless?

[micromuncher]

A microturbine requires a completely new energy source; can you imagine plugging a butane canister into your portable? All turbines have physical issues around energy lost through heat; remember in a traditional engine only about 50% of fuel burned actually goes to perform work.

Re:Small is not good for mechanical applications n

[LWATCDR]

I have to wonder how efficient it will be. Two things drive the efficiency of a gas turbine. The heat differentials and that leakage between the blades or impeller and the housing.
The leakage is going to be a real issue since it is a ratio between the disk size and the gap. Bigger engines mean a higher ratio. That is one of the reasons that BIG gas turbines are relatively efficient while small one suck fuel like there is no tomorrow.

Does it expel cabon dioxide?

[tinrobot]

I would imagine if it burns a fuel, it spits out carbon.

We need to stop burning stuff for our energy. Sure, batteries store energy made by mostly burning coal and stuff, but there other options for generating electricity to fill those batteries that don't involve adding carbon. I wish these people focused their research towards these types of energy sources.

Polution?

[iansmith]

Simple, small gas engines in lawnmowers and scooters are far, far dirtier than in a large modern car engine that has extensive polution control systems even when you take into account how much more gas a car uses than a lawnmower.

So I can't imagine this thing will run very clean at all. Not much room to put in a catalytic converter or other cleaning methods.

I have to wonder what a hundred million of these things running will do to indoor air quality. I don't think I want a thousand of these inside my office building.

Why???

[thepacketmaster]

Other than the obvious geek factor, why would we want to increase our dependancy on a fossil fuel.

Re:I wonder how safe they will be?

[Anonymous Coward]

ummm... that was 20,000 RPS not RPM

Re:Huge Amount of Energy + Small Space = Explosive

[drinkypoo]

What the geeks at MIT have done is to create a portable explosive device.

Short your Li-Ion battery with a nice fat conductor sometime and tell me what you get.

Disclaimer: I cannot be held responsible for any injury to person or property resulting from your potential stupid actions, whether I suggested them or not.

Wonderful

[eno2001]

Just what we need these days, not less but MORE dependence on fossil fuels. What idiots! Besides the obvious problem of trying to fuel something that small at the gas pump and then paying for it in fractions of a penny, what about the carbon dioxide emissions that conbustion engines produce? Aren't we going to be in for a lot of people with lots of headaches and brain damage from using a device like this? Even though it's so small, it's STILL emitting carbon dioxide which is known to cause the more serious cases of fatal death. I still get behind my roaring battle cry: SOLAR POWER IS WHERE IT'S AT FOLKS!!! The sun is an abundant energy source. Amp the solar panel production up so that they are 99.999% efficient, and you won't need any other source of energy anywhere on the planet. Combine that with electricity resevoirs that can hold a couple hundred gallons of electricity, and you have a clear winner. Thumbs down on this for sure.

Re:Cripes!

[oahazmatt]

I'm afraid that the whole snakes on a plane thing is already deader than dogshit.

Chips on a Shoulder! :)

Re:Pollution?

[bdonalds]

2-stroke lawn mower? I haven't seen one of those in ages. I think LawnBoy made two-stroke mowers for a long time, but I thought they were all 4-stroke nowadays. Now my chainsaw, leaf-blower, hedge-clipper and weed-trimmer, are a different story.

For non-gearheads: If you need to fill 'er up with a mix oil+gasoline, you got yerself a 2-stroke.

Re:p = mv & F =ma

[JesseL]

Well according to another article the turbine is 4mm in diameter, so google says .5 * 4mm * pi * 20000 is about 125.6 meters. 125 meters per second is about the velocity of a low end bb gun. Given my adolecent expirimentation in terminal ballistics, a similar low end bb gun will barely penetrate both sides of a soda can. It should be a simple matter to provide the engine with a scatter shield stronger than a soda can.

...or not

[Alef]

Packing a huge amount of energy into a small space is essentially creating a potential explosive.

Well, a bottle of plain water (about 1 kg of matter) contains roughly 100 petajoules (10^17 J), and still they are known to explode very infrequently. What matters is how stable the energy state is.

What about carbon monoxide?

[s_p_oneil]

Hot exhaust? What about poisonous exhaust? There's a reason people don't leave their car engines running in the garage with the door down. Can you imagine 50-100 laptops running these in a college lecture hall?