jump to navigation

Hybrid cars… Hybrid accelerators November 3, 2009

Posted by gordonwatts in accelerator, History, physics.

By now I think most people know how the Prius and other hybrid cards operate. Most cars’ breaks are just like a bycycle break: a clamp that generates a large amount of friction and slows the car down. This is a terrible waste of energy: the car’s motion is converted into heat and damage (to the brake pads) and can never be reclaimed. Think of it as wasted gas, excess pollution, etc.

Bicycle-Brakes[1] Hybrids are much more clever. They attach an electric motor/generator directly to the wheel and when you want to break then use the wheel’s motion to run the generator. This requires work – which slows down the car. Instead of the energy being lost, however, it is poured into a battery. The energy can then be reused to get the car started again. Huge savings in gas! This is also why hybrids tend to amazing at city driving, but not long distance driving (where this doesn’t help much because you aren’t stop/start).

Before we got sophisticated with generators and batteries we did something much more mechanical. At least for public transportation: the gyrobus:


Instead of a battery, however, a giant flywheel was used to store the energy. These things were built back in the 1950’s.

Guess what… the same technology has been used for particle accelerators – specifically the Bevatron!




These are 65 ton flywheels, and there are two of them. Here is an abstract from a paper that describes the control system that ran these puppies:

The Bevatron/Bevalac main guide field power supply stores 680 MJ in the flywheel-shaft systems of two independent motor-generator sets. During the normal acceleration cycle of various heavy-ion beams, the energies of the rotating shafts are converted to energy stored in the main magnet guide field. At the end of the acceleration cycle, the magnet energy is inverted back to the shafts. Generally, this takes place from 10 to 15 times per minute. The rapid switching of ions, energy, and beam lines at the Bevalac has required various control techniques for fast switching between all operational Bevalac fields within 1 min. The power supply control systems and operating parameters are described.

The principle is same as with the hybrid car, or the gyrobus, but all the sizes and power are extreme (as usual for the field of particle physics). Imagine spinning up and down those flywheels at a rate of once every 10 seconds or so! Of course, that system would never have fit in a car!

While I don’t know the answer to this, I suspect that flywheels are still one of the best ways to store energy that has to be quickly extracted over the timescale of seconds. Batteries probably can’t do it without costing a huge amount, and capacitors probably have a much lower energy density – though they are ideal for other stored energy applications that require much faster discharge times!



1. Stuart Coleman - November 3, 2009

I drive a Ford Fusion hybrid, and oddly enough I tend to get worse city mileage. If I’m really trying and have a nice full battery from a previous trip, I can get some really great city mileage (last week >50 MPG on my 4-mile drive to work). But it’s not a plug-in so the battery usually isn’t terribly full, and I don’t always have the patience to accelerate on battery (which is very slow, and where your worst mileage is if you’re not on battery).

However, driving on the highway is generally pretty even driving. Sure you don’t charge the battery much, but you’re using that nice efficient engine, and without trying can get 38-40 MPG easily.

Back to city driving, there’s one stretch on my commute where I go through 3 stop signs, and how much battery I have there can make or break my mileage. Same with getting a couple of lucky stop lights, being able to cruise at 35 MPH is a lot more efficient than stopping and then accelerating. Mostly because, this being any physical process, neither the slowing down nor the speeding up are perfectly efficient, and as I said accelerating is where the big gas use comes in.

Anyway, that’s my hybrid experience. Depending on how you define “city driving”, it can very easily be worse than highway if you’re not super-conscientious about it. Although if my car were a plug-in that would be a very different story…

2. Oklahoma Generator - November 3, 2009

very nice article, specially about the generator above, that is one strong generator..

3. Wendy Solberg - November 3, 2009

Nice article, thanks for the bycycle brake analogy- great demonstration! We are finally on the cusp of innovative, energy efficient automotive designs. Our work here will surely evolve as did the Wright borther’s first aircraft….

4. gordonwatts - November 4, 2009

Sure – and that is one heck of a generator, isn’t it!? Actually, I didn’t even realize the connection to modern tech when I first stumbled on this.

And, Wendy, as they say, often progress is just a matter of putting together several inventions that worked individually only-so-so into some package that is amazing. The iPhone, for example, is just a collection of already existing technologies into something quite compelling.

Stuart – that is very odd! It isn’t plug in – but I would have thought that it would shine in local driving. Certianly, the Prius that I rented from the UW motor pool showed significant gains. I wonder if there is a difference between the way they are constructed/programmed? I guess someone must have done a comparison (like Consumer Reports)…

5. chimpanzee - November 10, 2009

I just got back from SEMA 2009 (Specialty Equipment Manufacturer Assn), it’s pure “gearhead heaven”. It’s a world-wide event, that attracts ever conceivable Auto Mfr, from various markets. Including, Green Tech, Alternative Energy, etc. Hybrid, EV/Electric Vehicles, bio-diesel, etc. Check out some interviews & background videos I did:


Offroad Racing (extreme-duty application, ideal for Durability/Reliability testing for EV related technologies, like batteries — the key factor for EV)

[ note the “bad behavior” (burnouts in the parking lot, by “teen-agers posing as adults”) by the Rockstar Energy Pro 2 & Pro 4, see video here

Get a load of this: John Rogers/Jr, is a Princeton alumni (Mechanical/Aerospace Eng major) & Harvard Business School grad, who is starting his own Automotive Co “Local Motors”:


They are racing the Baja 1000 (the weekend, after this weekend), despite the danger of Drug Cartel chaos in Northern Baja

[ I was there in Nov/2006, where a drug cartel helicopter crashed a few miles downstream from my location. The dead body was taken back to the Ensenada morgue, which was subsequently raided by the drug cartel SUV. The attending doctor was kidnapped, killed, as was a police officer who attempted to stop it in the country. TRANSLATION: the drug cartel is WELL FINANCED & WELL ARMED (to the point of overpowering the local police). This violence (kidnappings, murders, etc) has continued in Northern Baja, & spread to S. California & even Phoenix/AZ. In an incident in the 2008 SCORE San Felipe 250, a hitman for the Drug Cartel was ARRESTED at the start line by the Mexican Feds. There was a tank on reserve, prepared to unleash its firepower (if required) at the start of the race. Like, here (early in the race), from the 2006 SCORE San Felipe 250. ]

Only goto Baja for the Offroad Races, if you travel in a group. Even so, be prepared for crime. My 4×4 van was TWICE the target of vandalism, Ensenada is a cestpool of crime. Although, recently security has been beefed up. Even so, it may not help. A famous team (McMillin Racing, they are behind the McMillin Realty/Homes of San Diego area) was the victim of a kidnapping/robbery, where a family was hijacked by the Zetas (enforcement unit of N. Baja drug-cartels, who were trained..are you ready for this..the U.S. Military!!??). Zetas use the same lethal firepower & tactics, as the U.S. Special Forces. That’s U.S. taxpayer dollars at work for ‘ya!!

On a more pleasant note, here is an interview with Kara Lawson/Amped Motors (EV ’33 Ford, chassis by Factory Five Racing):


Get this: she’s a Harvard alumni (originally a Math major, then switched to Art), from a sophisticated family on East Coast (New Jersey). Ballroom dancing required (white gloves, et al). She’s hooked up with her husband (Los Angeles based media guy), & they are selling a media-package for their EV project to the major networks. He’s a smart guy who developed software for derivatives trading, & they have 2 homes (Sonoma & Los Angeles). Now, THAT’s a business-model scientists should admire & strive to achieve. Get a side-business involving Technology (in this case Media & stock market trading), & get out of this ridiculous

“I’m a professor, & somewhat of an Educated Derelict (hardworking, smart, but poorly compensated)”

Myself, it looks like I’m making the right business-moves, towards a startup (possibly), or partnership with other Automotive Tech companies (mainly Alternative Energy). Dr. Stephen Koonin (MIT PhD in Nuclear Physics, former BP/British Petroleum Chief Scientist & former Caltech Physics Prof & Provost) is now Dept of Energy, Undersecretary of Science, along with Dr. Stephen Chu (former Stanford Physics Prof, Nobel Laureate) who is Secretary of Energy. The DoE has started the ATVM/Advanced Technology Vehicle Manufacturing initiative, which has supplied 450 million loan to Tesla Motors

[ all electric car company, which was co-founded by my former grad-school office-mate Martin Eberhard, M.S. in Electrical Eng @UIUC. Martin & I had the same M.S. Thesis advisor, & we’re both from the AI/Artificial Intelligence, Computer Vision, Robotics field. Another AI UIUC alumni (PhD ’93) is now Vice-President & Director of Research of SRA Int’l, a 700 million dollar U.S. defense contractor in Virginia (in the infamous Beltway of Washington DC) ]

Recently, I did a quick pass thru Caltech Physics Dept, trying to gain feedback on some ideas for EV + HEP initiative I’m working on. I.e., equip leading HEP physicists (experimental or theoretical) with state-of-the-art Super Cars, as part of a PR/Marketing campaign to jumpstart the “Public Perception” of Scientists as “Cool” (hipsters), instead of Boring/Dry/Intellectual (classic Albert Einstein image: Smart with a Bad Hair day..everyday).

I.e., you may see Gordon Watts tooling around U. of Washington, in a EV super-car. A $100K Tesla Roadster (0 – 60 in 3.9 secs), or a electrified Factory Five Racing GTM:

GTM Supercar

Joanne Hewett/SLAC has stated publicly on CV, that she wants a Tesla Roadster. I say, Gordon Watts should be setup in the above EV GTM (which I will develop, with fellow EV stinkheads around Caltech area). Then, have Joanne & Gordon meetup in a PR/Marketing promotional event, & “get crazy”. Like, “cruising with burnouts”:

SEMA cruising & burnouts

That would jumpstart the image of HEP physicists, revolutionize the Public Perception of scientists in general, thereby creating more Public Funding for Big Science projects, like Fermilab..right???

I.e., Gordon Watts goes from typical experimental HEP physicist (“Clark Kent”) to Hero of the Science Community (“Superman”). Similarly, Joanne Hewett (or Maria Spiropulu/Caltech/CERN) goes from typical theoretical HEP physicist (xxx, alter-ego of Bat Girl) to Bat Girl, fighting Crime (Dumbing Down of America, aka DDoA) in conjunction with Batman (Sean Carroll/Caltech, who is currently stuck with the gas-guzzling Jaguar). BTW, Maria Spiropulu already took a test-drive in a Tesla Roadster (in Switzerland), & knows Elon Musk. I’m friends with EM’s ex-wife Justine (Queens Univ grad, “Harvard of the North”), the famous novelist.

Oh, & BTW, when Gordon achieves media super-star status (darling to Film/TV & iTunes video), he will need an Agent. Hollywood, baby.. Lisa Randall/Harvard, already gets HUNDREDS of emails per week, about Entertainment proposals.

I’m just wondering how Fame/Fortune will goto Gordon’s head. Will he stay married with his wholesome wife, or will he become a ranging voyeur (taking lessons from Tommaso Dorigo, a known admirer of young females), & start “playing the field”? I.e., changing spouses like one changes socks: “on a daily basis”.

Oh yeah, here are videos of SEMA hotties:

SEMA Trophy Girls

I can detect T. Dorigo’s drooling eyes..right about now. BTW, Courtney Day is a college grad (Communications & Marketing major), who negotiates her own deals (in this case, K&N Filters). No agent required.

6. Rick Baartman - January 3, 2010

so anyway, it’s “brakes”, not “breaks”.

7. Gordon Watts - January 4, 2010

Thanks, indeed! I never could spell!

8. jagurlavender - February 1, 2010

if we foolow about hybrid vehicle we mus be surprise, i thing that technologi still the best for this time

9. Eric - March 11, 2010

Hybrids do tend to weigh more though, there’s simply more equipment. I think they make more sense if you have a plug-in, so you’re using the electric motor anyways. It seems to me that if you hyper mile a normal car, you should get the similar mileage to a hybrid (or better?). There would be less energy recovered on braking, and the car would weigh less, to boot (but who would drive like that?). If you were to hyper mile a plug-in hybrid though, you’d run on electricity longer and gain much better savings, perhaps.

10. gordonwatts - March 11, 2010

How do you measure gas milage in a plug-in car? 🙂

11. Eric - March 11, 2010

Good point! A better wording might be to “reduce gas consumption”. Even so, most of the electricity in the US comes from coal, so it’s not a clear win.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: