Honda touts heat-harnessing hybrid technology
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]
Reader Comments (Page 1 of 1)
rem83 8:25AM (2/21/2008)
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.
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mikomi 8:35AM (2/21/2008)
Steampunk!
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Ryan M 9:28AM (2/21/2008)
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.
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e36 9:35AM (2/21/2008)
This sounds cool, but hybrid is not the way of the future. This is it http://www.youtube.com/watch?v=QmqpGZv0YT4
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Yar 9:47AM (2/21/2008)
Are you serious? Steam power? Since thats not dangerous or anything, Soccer Moms driving steam-powered Hondas.
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Mehul 10:01AM (2/21/2008)
Is the tail pipe heat enough to turn water into steam?? I didnt think it that high..
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I drink your milkshake 10:07AM (2/21/2008)
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.
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Fast evo 8 10:35AM (2/21/2008)
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.
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equipe 10:59AM (2/21/2008)
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.
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mikomi 10:59AM (2/21/2008)
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.
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blackstripe77 12:00PM (2/21/2008)
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
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Dan 12:06PM (2/21/2008)
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?
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NT 12:39PM (2/21/2008)
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.
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Franz 2:12PM (2/21/2008)
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.
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