Hybrid vehicles have always offered more benefits to the zip-around-town Domino's pizza delivery boy than the long-distance highway commuter. In fact, without regernative braking at work, a hybrid vehicle at highway speeds exhibits very few efficiency advantages over a frugal MINI Cooper.
Addressing one of the problems, Honda is now touting a "heat-harnessing hybrid", claiming it can recapture energy that most conventional hybrids lose during high speed driving. Greatly simplified, the innovative approach uses exhaust heat to convert water to steam. The steam turns an electric generator that then charges the vehicle's battery pack. It's all based on an age-old principle called the "Rankine cycle." Pre-boomers may recall it's the same type of technology that was used in the Stanley Steamer a century ago.
Honda crammed all of the "heat-harnessing" plumbing into a Honda Stream prototype and captured three times as much energy as a regenerative braking system on the EPA highway cycle. While that may sound impressive, the technology still needs to come a long way and the price fall before we find steam generators in our cars. Thanks to Sylvester for the tip!
[Source: ecogeek]
New KITT Attack Mode revealed at Comic Con
London 2008: Honda OSM concept roadster says, "Cheerio!"
London 2008: Lotus unveils the Evora
2010 Chevy Camaro - Official Details and Images
2010 Chevy Camaro - LIVE from the reveal
First Drive: Maserati Quattroporte S in Europe
First Drive: 2008 MINI Cooper S JCW
In the Autoblog Garage:2009 Nissan GT-R
North American Exclusive First Drive: Alfa MiTo
First Drive: 2009 Kia Borrego
Reader Comments (Page 1 of 1)
rem83 @ Feb 21st 2008 8:25AM
so this sounds pretty similar to the system developed by BMW that was demonstrated 2 something years ago: http://www.gizmag.com/go/4936/
Also, Atkinson cycle hybrids still show significant gains over comparable Otto cycle vehicles at highway speeds, especially when the engine is sized small enough to require electric boost for satisfactory acceleration performance.
mikomi @ Feb 21st 2008 8:35AM
Steampunk!
Ryan M @ Feb 21st 2008 9:28AM
Sounds great, but it sounds like we still can't really run the electric motor at freeway speeds. So once I get those batteries charged up from the steam engine...then what? Then the generator sits around and makes energy that can't go anywhere until I slow back down to city speeds.
Besides that, where is the water coming from? Are they capturing water from the exhaust/combustion cycle, or do I have to put water in it? If I have to put in 2 things regularly (Gas and Water) I'd just assume plug the thing in at night and be done with it.
e36 @ Feb 21st 2008 9:35AM
This sounds cool, but hybrid is not the way of the future. This is it http://www.youtube.com/watch?v=QmqpGZv0YT4
Yar @ Feb 21st 2008 9:47AM
Are you serious? Steam power? Since thats not dangerous or anything, Soccer Moms driving steam-powered Hondas.
Mehul @ Feb 21st 2008 10:01AM
Is the tail pipe heat enough to turn water into steam?? I didnt think it that high..
I drink your milkshake @ Feb 21st 2008 10:07AM
You are late to the party. This was on Engadget two days ago. I think some are spending WAY too much time around the tail pipe.
Fast evo 8 @ Feb 21st 2008 10:35AM
and both honda and BMW stole my idea (at least i like to think so). i even posted my idea on our college car club forum a full year before BMW released their article. ironically the BMW system was called the turbosteamer, and i called mine the thermocharger. both had identical concepts, heat exchanger on the exhaust, utilizing the existing water cooling system on the car to extract even more energy from heat, water pumps, and the power generating turbine. guess i should have patented the idea before i posted it on a public forum huh.... doh!
here is my idea (read about it half way down the thread):
http://hopecarclub.org/forums/viewtopic.php?t=179&postdays=0&postorder=asc&start=15
and the BMW concept can be read about in the gizmag link. and honda is late to the game.
equipe @ Feb 21st 2008 10:59AM
I wonder if you could hook up a turbocharger to a small generator if you're not going to use it to boost an engine. The motion of the exhaust is wasted kinetic energy in a non-turbo engine. Put it to some use. (any engineering types out there know more about the feasability about this? My knowledge of Thermodynamics is quite limited)
There should still be enough heat to add the steam system too... Now that's efficient. Heavy, but efficient.
mikomi @ Feb 21st 2008 10:59AM
Considering the basis for this technology was in use 100 years ago, you could say everyone is stealing. But let's look at it with an open mind (if possible). Right now the benefits seem minor, but who knows what potential benefits we might reap if there's prolonged R&D on this technology. The ICE enjoyed over 100 years of constant R&D refinements, I'm sure other technologies have some potential, but we first must be willing to invest in them.
Besides, I would love me some steam cars. Just because I like the idea. Although whether or not this technology proves to be economically viable, I have no clue. I fear that my arm-chair physics+mechanical engineering degree doesn't cut it.
blackstripe77 @ Feb 21st 2008 12:00PM
Just a note, but the Stream displayed is a second generation Stream, while the concept is in a first generation 2.0l Stream. See vtec.net
Dan @ Feb 21st 2008 12:06PM
This works on the tailpipe? What is being done meanwhile with the RADIATOR? You know, the great big thing on the front of the car that's for the sole purpose of wasting heat?
NT @ Feb 21st 2008 12:39PM
Where are you guys getting this tailpipe from? If I'm interpreting the illustration correctly it would use the heat from the engine block, which is more than adequate to boil water. Think about it, they say anywhere from 1/2 to 3/4 of energy is lost in combustion to heat, so why not capture some of the lost energy to drive a steam turbine. You don't need to fill it with water if it is in a closed loop, the steam would evaporate, and then recondense as it cools...It is the same way steam turbines work. This would be the same application but on a smaller scale.
Combines with regenerative braking, I say it would add a good charge to batteries. Honda has already proven it can use electric motors to improve acceleration, so you could use it at highway speeds, or to improve acceleration and any other number of improvements.
Franz @ Feb 21st 2008 2:12PM
It's nowhere near feasible for production, but I'm sure it'll get there if they work at it. If it were up to the skeptics, we'd still be riding around in horse-drawn buggies. I like when companies try to innovate and raise the bar.