I have only had basic physics in school and there are alot of ways we could make a car that would get GREAT milage. One exzample would be to use the energy created during breaking to help get the car rolling again by converting it to air pressure. Very simple plan.

 

This is true, but there's always more to it.

For instance, your regenerative braking would help a lot for in-town mileage, but not so much on the highway.

Secondly, it would add significantly to the cost of a vehicle. You now have what amounts to an air compressor, lines, a tank, and the contol mechanism to deal with. A plus side is you would always have compressed air on tap, in case of a flat tire!

There are lots of ways to get better mileage. But you throw practicality into the mix, and it gets real complicated, real quick. And that's where the fun begins!

How about this:

Have the engine equipped with headers, which would run through a boiler. The boiler is filled with water. As the water boils due to the heat from the headers (otherwise wasted), the pressure can be used to drive a piston or pistons connected to the drive axle. It would be throttled on the same gas pedal as the engine. Or maybe it would be run into the same tank as your regenerative braking tank for even more efficiency?

 

The added weight from the regeneration system cuts fuel mileage!

There was a car recently in one of either Popular Science or Popular Mechanics (or maybe even some other magazine -CRS) that had a regen system and energy conversion system in it.

 

I've heard mention of a hydraulic system doing something of that nature, it basically would use hydraulic motors to slow the vehicle, storing it in a spring pressurized reservior that would help get the vehicle going again.

 

Someone should build a hybrid kit that can be fitted to almost any small front wheel drive car. It would drive the rear wheels up to a speed where the engine could take over in a higher gear......very simple .

 

I think the more common way of doing this will be electric motors, that act as generators when braking, charging the batteries.

 

Wouldn't that be less efficient, since you're converting it from mechanical energy to electrical energy and back again?

 

In theory, you could even have both the electrical and hydraulic regen systems hooked up. The electrical system works by induction, same as a generator, having magnets moving inside of a wire coil. The hydraulic system takes the kinetic energy from the wheels and stores it under pressure. Both systems can store energy, both systems can release the energy, both systems have their drawbacks...and both systems are being developed. There was an article on here a little while back about the 60mpg F-150 with the hydraulic hybrid technology, and companies have been using the electrical regen for a while. I've personally drove cars with the electrical regen (I think it's either the Prius or Civic Hybrid) that have a gauge on the dash that tells you how much power is being restored as you're braking.

 

Just think,There are high paid engineers and tech brains who dont have any better ideas than we laymen do. Makes me want to raise enough money to build a proto-type myself.

 

Not really, if you're talking about an electric hybrid vehicle, the electric motors are already there, all you have to do is put a load on the electrical system for it to slow down and charge the batteries. With an added energy recovery system, that isn't the actual propulsion system, you have all that added weight, which is probably just as inefficient.

 

the solution is a nuttier, stable fuel...the more potential enery a fuel is capable of, the less amount of fuel it will take to create equal amounts of power as a less potent one. Practical? The added fuel cost would be the same as paying for the extra parts/technology as a hybrid.

How about this....an electric motor, with a charging system in the driveline so it replenishes the power required to drive the battery. That would take alot of engineering to figure out how to turn a small amount of current into a large amount, safely.

option three...1000cid 8+ cylinder engine, 30psi of boost...walk on it hard, shut the engine off and coast lol

 

You're right, that would take a lot of engineering. Impossible things tend to be like that. Like putting a windmill on your car and expecting the "wind" you create by driving to charge your battery enough to continuously drive the car.

I posted a lot of links to recent articles on "Hydraulic Hybrids" in this thread:
Hydraulic Hybrids
A good description from an Australian company that is in the market:
Hybrid Comparisons

There are some advantages over electric hybrids like no battery replacement cost and a larger percentage of braking energy converted back to hydraulic potential as compared to electric energy. And some disadvantages, namely no real improvment in highway fuel mileage due to hydraulic system (you're basically driving a "normal" ICE vehicle on the highway, with the added weight of a hydraulic system).

Several larger companies have looked into this, Eaton, Dana, Ford, and the EPA to name a few big ones. Ford even had a system on their F-350 Tonka concept a while back. Seems like most of the efforts are to build larger delivery/garbarge trucks as these make frequent stops and could benefit most from such a hydaulic system. A smaller company, Hybra-Drive, is working on a retrofit system for a Hummer. They started by making a '68 Beetle hydraulic hybrid, so it'll be interesting if they can make a retrofit system for other light trucks and cars.

-Jim

 

There's nothing simple about automotive mechanics, take it from someone trained in engine mechanics and design as a Mechanical Engineer (note I don't do this for a living and never have).

The basic IC engine is for all intents and purposes at the peak efficiency it can attain using current fuels and driving patterns. Notice I tossed in driving patterns, because that is where fuel efficiency takes the hit. Engines running at constant RPM get excellent fuel efficiency, hence the trials with hybrid vehicles. Gasoline is about as effective a fuel as anything we're likely to develop - but all those darn pollutants need to be cleaned up, and efficiency takes a hit from them too.

 

Even simpler physics, F=ma, Force (HP) = mass (weight) x acceleration.

Take the weight out and slow down. People want faster and faster cars and trucks with more and more saftey and luxury features. All the advances in powertrain efficiency that should result in increased gas mileage have been wasted on excess weight and lead left feet.

Look at the curb weght of the typical 2007 "light" truck compared to the 1960's. Many new F-150's top 5000lbs, empty! A typical F-250 used to be around 4200. 0-60 and quarter mile times have dropped dramatically as well.

Jim

 

That has something to do with it, but not as much as you might think.

Acceleration is what kills the gas consumption, which is why engines running at a constant RPM get better milage - they don't accelerate. Park the engine at its optimal RPM and keep it there. Want proof, talk to a tow rope operator at a ski resort. True, wind resistance becomes a factor at around 60mph, but look at your milage from driving a full tank at highways speeds, and that same milage from driving around town on a full tank - MASSIVE difference. The acceleration, stopping, idling, all of that is huge.

But to take your advice, drive a long long distance at 35mph and compare fuel economy - again huge difference.

BTW: I did do this all the time. I drive from Seattle to Spokane routinely and on average I get about 24 mpg, driving to and from work I get about 17mpg, during the winter when the roads turn to ice, I have had to drive from Seattle to Spokane at 35 mph - I got something like 30 mpg on that trip. It wasn't a fun trip, my fingers embedded in the steering wheel, and it took me about 7 hours - but I got great milage.