MSU receives $2.5 million DOE award to build advanced hybrid engine

[Right Lane Cruiser]

"Wave" of the future?

Sean Welch - CleanMPG - October 30, 2009

Dramatic improvements in fuel economy can be obtained by boosting the ratio of electric to fuel powered propulsion in plug-in hybrids. What about the engine or generator, though?

Michigan State University researchers have received a $2.5 million federal stimulus grant from the U.S. Department of Energy to build a prototype new engine and generator technology that can dramatically improve efficiencies and reduce costs of electric hybrid vehicles.

The project has the potential to increase automotive fuel efficiency by five times compared to internal combustion engine cars on the road today while reducing costs by 30 percent. About the size of a large cooking pot, the novel, hyper-efficient engine could replace current engine/generator technologies for plug-in hybrid electric vehicles.

The award will allow a team of MSU engineers and scientists, led by Norbert Mueller, an associate professor of mechanical engineering, to begin working toward producing a vehicle-size engine/generator known as a wave disk generator during the next two years – building on existing modeling, analysis and lab experimentation they have already completed. The WDG uses a turbo combustion “shock wave” technique to efficiently convert gaseous (compressed natural gas or hydrogen) or liquid fuel sources to electrical power.

“Our goal is to enable hyper-efficient hybrid vehicles to meet consumer needs for a 500-mile driving range, lower vehicle prices, full-size utility, improved highway performance and very low operating costs,” Mueller said. “The WDG also can reduce carbon dioxide emissions by as much as 95 percent in comparison to modern internal combustion vehicle engines.”

The small, lightweight unit could replace the automotive internal combustion engine, the radiator/water pump, fuel/air control, transmission and generator found in today’s hybrid vehicles. The result is a hyper-efficient serial hybrid vehicle with very little equipment under the hood.

MSU’s WDG project is one of 37 Advanced Research Projects Agency-Energy recently funded by DOE. It was chosen from among more than 3,600 initial concept papers through a rigorous review process, which included input from multiple review panels composed of leading U.S. energy science and technology experts, and ARPA-E's program managers.

Evaluations were based on the potential for high impact on ARPA-E's goals – to develop creative and inventive approaches to transform global energy production and efficiency, while advancing America's technology leadership. It was part of the first round of projects funded under ARPA-E, which is receiving a total of $400 million under the American Recovery and Reinvestment Act.

The days of full sized engines in hybrids may be quickly drawing to a close.

[xcel]

Hi Sean:

Originally Posted by Right Lane Cruiser

The days of full sized engines in hybrids may be quickly drawing to a close.

___I can only hope this truly does bear fruit...

___Good Luck

___Wayne

[SlowHands]

Impressive idea, I too hope this works as well as their experimental devices.

[brick]

I have been working throug the numbers and I guess it's possible. I think their claims are a bit optimistic, though. I just managed to dig up a paper [PDF] that does a bit more to explain what a WDG is and how it works. I won't pretend to understand it. But this paper does give some conversion efficiency numbers to chew on: 13-16%. That was an early paper in 2006 so no doubt that number has been improved upon. This is a form of turbine, so additional stages might improve eficiency. And it sounds like blade and port design are a big deal.

As I understand it (which is probably not well) this thing depends on some sort of resonance to compress the combustion gasses instead of the usual mechanical compression. This means, and the paper seems to support this notion, that the engine will only work properly when it's spinning at just the right speed. This is a challenge for an automotive application because it means that it will rarely produce the amount of power that you require at a given time. So it makes perfect sense that you would use it as a genset for a serial hybrid, which can just switch the thing on and off as needed to keep the battery charged. The conversion efficiency of the generator (let's call it an optimistic 60%...that's about the upper bound for a heat engine) is compounded by the efficiency of getting it into the battery pack (the best I'm aware of is something like 85%) out again (there's another 85%) and to the wheels (which we will call 90% since inverters are getting pretty good and I feel like being generous). .6*.85*.85*.9 is 0.39...39% conversion efficiency. And of course that's quite good. Given that the atkinsonized ICE in the Prius is good for about 30% and that there are some additional losses in the drive train (lets call the whole thing 25% at steady-state), I'm going to estimate that this improves my 60mpg at 60 mph to ~95mpg.

So there could be something to this. But the question I want to ask is, does this technology in and of itself represent a revolution? That's what they seem to want us to think. And I don't quite buy it. The only way to get near to their claim of a five-fold efficiency benefit is to compare a really old-and-busted 20mpg vehicle to my theoretical series hybrid with a 0.26 coefficient of drag. And that's an apples to walnuts kind of comparison. The benefit has little to do with the wave disc thing by itself. The best you could possibly expect over current ICE technology is about double the conversion efficiency. (Less if you consider what a good diesel can put down.) I also take serious issue with the claim of 95% reduction in carbon dioxide. C02 emissions are proportional to fuel burned.

Of course the potential for simplicity is very nice. Fewer moving parts means that it ought to be cheap. But you need the big batteries to make it work, and those won't be cheap for a while yet.

I need more info I think. The information I have at hand is only just enough to get me thinking, not enough that I can draw conclusions.

[antrey]

Very nice analysis, brick!

[xcel]

Hi Tim:

___Thank you as well!

___Good Luck

___Wayne

[ItsNotAboutTheMoney]

Originally Posted by brick

...and to the wheels (which we will call 90% since inverters are getting pretty good and I feel like being generous). .6*.85*.85*.9 is 0.39...39% conversion efficiency. And of course that's quite good. Given that the atkinsonized ICE in the Prius is good for about 30% and that there are some additional losses in the drive train (lets call the whole thing 25% at steady-state), I'm going to estimate that this improves my 60mpg at 60 mph to ~95mpg.

....

Of course the potential for simplicity is very nice. Fewer moving parts means that it ought to be cheap. But you need the big batteries to make it work, and those won't be cheap for a while yet.

Cheap would be great. Especially given that if it works they'll screw everybody on the license costs.

Another question is the weight. Would it be lighter than other generators?

I'm really looking forward to future developments and desperately hoping that the efficient car we get next will seem like a gas guzzler in 10 years time when we replace it again.

[Ken Seal]

If this is even close to being possible..... why is there only $2.5 million being allocated?

[xcel]

Hi Ken:

___Welcome to CleanMPG and good question!

___Good Luck

___Wayne