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New Gasoline Engine Prototype Claims 3X Current Engine Efficiency 377

erfnet writes "A cool new high-efficiency gasoline engine prototype has no radiator, no pistons, no valves, no transmission, and no fluids (except for the fuel). At first glance it has a few similarities with the Wankel engine, but is more advanced. The engine is only suited for hybrid-electric vehicles, but that's okay. The efficiency they are claiming: is over 3x what today's gasoline engines produce. The developers, a team at Michigan State University, hope to have this engine on the market in the next two/three years."
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New Gasoline Engine Prototype Claims 3X Current Engine Efficiency

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  • Some amazing claims.. I hope they'll be able to prove them..

    Although I'm more hoping for huge leaps in renewable fuel technology. The more efficient petrol based fuel engines become, the less funding for other techs.

    • by tepples ( 727027 ) <.tepples. .at. .gmail.com.> on Saturday April 09, 2011 @09:34AM (#35767300) Homepage Journal

      Although I'm more hoping for huge leaps in renewable fuel technology. The more efficient petrol based fuel engines become, the less funding for other techs.

      One problem is the tax structure.

      As for petrol: Production of renewable fuel for petrol vehicles (that is, ethanol fuel) isn't exactly efficient outside of perhaps Brazil. As I understand it, producing ethanol from sugarcane is more efficient than producing it from corn. But most countries that demand petrol and ethanol are , and they've enacted import tariffs and farm price supports to make the corn method artificially more attractive. This could change if researchers perfect production of ethanol from switchgrass.

      As for diesel: Soy biodiesel already has a positive EROEI, and production of biodiesel from microalgae looked promising last time I checked. But diesel is more commonly used on trucks and buses than on cars. A lot of U.S. cities lack good bus transit, and apart from Volkswagen's TDI vehicles, few automakers want to try marketing diesel cars in the United States, even after the nationwide switch to ultra-low-sulfur diesel a few years ago.

      • by PPH ( 736903 ) on Saturday April 09, 2011 @10:46AM (#35767776)

        few automakers want to try marketing diesel cars in the United States, even after the nationwide switch to ultra-low-sulfur diesel a few years ago.

        Easy solution: Throw out US regulations that artificially create an isolated market for vehicles and allow people to import vehicles from overseas. I've done it before they tightened up the rules protecting US dealerships. Several vehicles that I've purchased (Toyota Landcruiser, for example) are available overseas in diesel versions. I would have bought one (much better mileage than the gasoline version) had it been legal to import.

        • by Lehk228 ( 705449 )
          what makes you think congress will loosen regulations (liked by democrats) which act to artificially prop up businesses at the cost to the everyday american (liked by republicans)
        • It's not just import tariffs; Mercedes has an ultra-efficient gasoline engine that they won't import to the US because our gas (not Diesel) has too much sulfur. (link [gas2.org])

          And then we have the massive resistance of USians towards Diesels in cars. Part of that is the cash-grab that the States go for by taxing the hell out of Diesel fuel, intending to get a piece of the interstate trucking money. Part of it is probably backlash from the horrible gas-to-Diesel conversions from US automakers in the 1980s.

          I don't k

        • The reason we all drive gasoline vehicles is because there's not much other use for the gasoline that comes from a barrel of crude. Diesel has more energy per gallon, it's inherently a better automotive fuel, but if we all drove diesel vehicles, gasoline would be free.

          In the US, the trucking fleet uses the diesel fuel - leaving the gasoline leftover for everyone else. If there were suddenly no more semi-trucks, then, yes, we could introduce more diesel cars into the mix.

          This balance is more the reason you

      • I've read that every gallon of corn ethanol takes a gallon of gasoline to produce. It also takes about 1870 gallons of water for that amount of corn to grow. A decreasing water table has been a fact in the midwest for decades.

        Ethanol is also harder on engines. And according to consumer reports, mpg is worse on the standard 0.9 gasoline 0.1 ethanol mix than if you just took the decrease amount of gas w/o ethanol. (I.e. 10 gallons of mix gas takes you less distance than 9 gallons pure gasoline.) This mea

        • It's all the prop up the Ethnol industry that gets funded by our tax dollars. No one wants E85 so they are forcing companies to make all gasoline E10. Heck, soon you should be seeing E15. What a joke...
      • by Intron ( 870560 )

        Corn-based ethanol is looking less and less attractive:
        http://futures.tradingcharts.com/chart/CN/M [tradingcharts.com]

        Too bad US politics is disproportionately influenced by the Iowa caucus. Other wise ethanol subsidies would be gone.

      • by jvillain ( 546827 ) on Saturday April 09, 2011 @01:14PM (#35768798)
        Diesel cars are quite popular in Europe and a few other places. The reason why you haven't seen a lot of them in North America is that the quality of the diesel over here sucked rhinos until very recently. The European standards for diesel require much less sulphur etc than North America. Our diesel would clog up the engines they use and would wreck the emission systems. As for the story. They are no where with it and looking for funding. By the time it is ready for the real world it will be 5 times the size and produce half the power due to the realities of having to run all the time with out constant repairs. There are a 100 claims like this every week but yet some how it never makes it into an actual production car.
  • Though an article with more technical details (I couldn't find anything going through the linked websites) might help.
  • by dougmc ( 70836 ) <dougmc+slashdot@frenzied.us> on Saturday April 09, 2011 @09:15AM (#35767176) Homepage

    The Wave Disk Generator uses 60 percent of its fuel for propulsion; standard car engines use just 15 percent. As a result, the generator is 3.5 times more fuel efficient than typical combustion engines.

    They're claiming 60% efficiency? It's still a heat engine, so their absolute maximum efficiency is based on how hot they can get things and how cold it is outside, and I'm skeptical that they can get it hot enough for 60% efficiency from gasoline. (Actually, I don't think they said gasoline -- I don't think they said any specific fuel.)

    And what's this thing about "the engine is only suited for hybrid-electric vehicles, but that's okay. " ... what does THAT mean?

    Somehow I doubt this is going to pan out quite like they say it will.

    • Re: (Score:2, Informative)

      by Anonymous Coward

      "what does THAT mean"

      I believe the engine runs best at constant speed making if suited for electric generation, not powering stop & start driving.

      • We already have an efficient engine type that fits those exact characteristics, the stirling engine. (Maybe this new one is much lighter).

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      And what's this thing about "the engine is only suited for hybrid-electric vehicles, but that's okay. " ... what does THAT mean?

      I think it means the engine can only go at a single speed, unlike a standard engine that can change speed as you accelerate. So instead of driving the wheels from this single-speed motor, you charge a battery, and use the battery to drive the wheels at different speeds.

    • Re:skeptical ... (Score:5, Insightful)

      by EvilRyry ( 1025309 ) on Saturday April 09, 2011 @09:23AM (#35767224) Journal

      And what's this thing about "the engine is only suited for hybrid-electric vehicles, but that's okay. " ... what does THAT mean?

      Most likely it means that the engine has terrible spin up/down times and/or is inefficient at doing them. Its best operated at constant speed, generating electricity for an electric motor which actually pushes you forward.

      • Re:skeptical ... (Score:4, Interesting)

        by dougmc ( 70836 ) <dougmc+slashdot@frenzied.us> on Saturday April 09, 2011 @09:31AM (#35767278) Homepage

        And what's this thing about "the engine is only suited for hybrid-electric vehicles, but that's okay. " ... what does THAT mean?

        Most likely it means that the engine has terrible spin up/down times and/or is inefficient at doing them. Its best operated at constant speed, generating electricity for an electric motor which actually pushes you forward.

        That would be my guess too.

        But that could be handled with a CV transmission too.

        Perhaps it can't be throttled down easily, so it's always putting out full power, so it either needs to be charging a battery or powering the car or shut off if neither is needed?

        But even so, if it's 60% efficient, that's huge -- more efficient than our large turbines that power power plants, ships, etc. -- these things would easily tolerate an engine that takes a long time to spin up or down, or could only be run at full power or speed. It's not just hybrids.

        • Re:skeptical ... (Score:4, Interesting)

          by Junta ( 36770 ) on Saturday April 09, 2011 @10:02AM (#35767516)

          The only concrete spec I could find that could be tied to this was the 25 kw (33 hp) power max. That might be enough to have somewhat more-than-required power at unambitious cruising speeds, but would absolutely not be able to deliver sufficient acceleration and therefore need to save up excess capacity (when available) in a battery and delivered via an electric motor.

          Also, hypothetically, if the spin-up time was ludicrously slow, a CV would not help a car go from a stopped position up to highway speed.

          • by dougmc ( 70836 )

            Also, hypothetically, if the spin-up time was ludicrously slow, a CV would not help a car go from a stopped position up to highway speed.

            The only reason I can think of to have a ludicrously slow spin-up speed would be if it was really heavy -- but they explicitly say it's light.

            But even if it takes a minute to speed up, they could just run it at full speed all the time and modulate the power it emits to whatever is needed to maintain speed. I do imagine that this would hurt efficiency somewhat. Perhaps put two or three in a car and shut 1 or 2 down when not needed? Unless it's always working at full power at full speed, of course.

            Personal

      • by Greyfox ( 87712 )
        Kind of like a turbine, which have been around for decades and are also "Very similar to a wankel engine."
      • Most likely it means that the engine has terrible spin up/down times and/or is inefficient at doing them. Its best operated at constant speed, generating electricity for an electric motor which actually pushes you forward.

        Much like modern trains except they have diesel engines.

    • by nurb432 ( 527695 )

      And what's this thing about "the engine is only suited for hybrid-electric vehicles, but that's okay. " ... what does THAT mean?

      My guess is that it wont handle rapid speed changes well and is most efficient at a constant speed, so running a generator is about the only thing it will do well. Just like any other turbine.

      • The last gasoline engines to do about 15% efficiency were two strokes. Modern ones do more like 25-30. Diesels achieve 35-45 (or even more in marines engines.) To get a high efficiency you need a high compression ratio and a relatively large combustion chamber to reduce heat loss (around 400-500cc seems to be the best tradeoff, while some CR Diesels are achieving peak combustion pressures up to 180 bar. Yes, that is combustion pressure, not injection pressure).

        Now, modern variable vane turbocharged Diesels

    • by v1 ( 525388 )

      And what's this thing about "the engine is only suited for hybrid-electric vehicles, but that's okay. " ... what does THAT mean?

      That usually means it can't produce high impulse power, like accelerating from a stop. It uses the batteries to buffer power production and recharges this during lower consumption, uses regenerative braking, etc.

      That brings up the worry that it has a low average impulse output, which becomes a problem when you need continuous higher output, such as when out on the highway. It may

      • by Kupfernigk ( 1190345 ) on Saturday April 09, 2011 @10:04AM (#35767532)
        There is no problem at all with maintaining legal highway speeds with a hybrid; the gasoline engine is designed to be able to maintain a speed on the level of over 100mph. US cars tend to be vastly over-engined because...because other cars are vastly over-engined, hence the fuel-glugging traffic light/highway merge race. The hybrid is a very logical solution to the problem of providing an engine with sufficient power for cruising, with a booster available for acceleration. After over 20 years of Diesels, I've now decided that hybrids are Good Enough for my next car. This is partly because I suspect that rising oil prices are going to force a change in driver behaviour; many of the worst drivers are probably only marginally able to afford their vehicles.

        The difficulty with this thing is that it is NOT suitable (if you read the article) for a hybrid. That's because the engine is unsuited for use as the baseload prime mover. It is only suitable for a full electric transmission with battery storage. Full electric transmissions are expensive and inefficient and, as I note in another post, probably can't compete with plain old Diesel.

        I've been looking at full electric transmission for my next boat design, using a constant speed generator Diesel to run a large alternator with direct drive to the motors and auxiliary battery to enable short term high power (i.e. twice the generator output for an hour.) So I have been doing the maths...and it doesn't add up. It is more efficient and cheaper to have a small Diesel prime mover topping out at 2400rpm, and an auxiliary electric motor to boost shaft speed to 3000 for short periods(owing to the cube law, both motors have the same power.) I'm just confirming what Toyota and others already found out - hybrid is the most efficient.

        • by shmlco ( 594907 )

          Why bother with transmissions, crankshafts, axels, and so on? Just extra weight to haul around. Hubless eletric motors on all wheels.

          • by atamido ( 1020905 ) on Saturday April 09, 2011 @12:00PM (#35768360)

            Why bother with transmissions, crankshafts, axels, and so on? Just extra weight to haul around. Hubless eletric motors on all wheels.

            The added weight makes them horribly inefficient for anything except very smooth streets. Super heavy wheels tend to be a bad thing. This concept has worked well for some things, such as city buses where the city has well paved streets.

    • They're claiming 60% efficiency? It's still a heat engine, so their absolute maximum efficiency is based on how hot they can get things and how cold it is outside, and I'm skeptical that they can get it hot enough for 60% efficiency from gasoline. (Actually, I don't think they said gasoline -- I don't think they said any specific fuel.)

      Carnot efficiency doesn't enter into it; gasoline easily burns hot enough to do 60% efficiency with a room temperature cold reservoir.

      • Carnot efficiency doesn't enter into it; gasoline easily burns hot enough to do 60% efficiency with a room temperature cold reservoir.

        Yes, but what do you hold the burning gasoline in? Common steels lose their strength at a few hundred C, limiting your Carnot efficiency quite a bit. Even the high-temperature alloys [haynesintl.com] used to make aircraft turbines start to get a little soft at the necessary temperatures. Turbine engines solve that problem by limiting the stress on the turbine blades, but this engine must e

    • by quenda ( 644621 )

      They're claiming 60% efficiency?

      No, TFA is bullshit. 60% is the theoretical maximum, which is the same as a steam/gas tubbine. Is this one?
      They don't say what the prototype achieves. Diesel can be 35%, which is the current choice for a series hybrid, e.g. locomotives.

      "the engine is only suited for hybrid-electric vehicles, but that's okay. " ... what does THAT mean?

      It probably means the engine is constant speed. Maybe useful in parallel hybrid with CV gearbox?

    • by hitmark ( 640295 )

      http://www.blogcdn.com/green.autoblog.com/media/2011/04/wave-disk.jpg [blogcdn.com]

      seems like they have basically nailed a (improved?) wankel in front of a generator.

    • by Greyfox ( 87712 )
      Plutonium. It has to run on Plutonium.
    • It means... (Score:4, Informative)

      by Pollux ( 102520 ) <speter@[ ]ata.net.eg ['ted' in gap]> on Saturday April 09, 2011 @10:15AM (#35767608) Journal

      You didn't read the flippin' article.

      If you had, you would have likely watched the youtube vid that explained the concept.

      This engine is not an engine that directly propels a vehicle as a standard internal combustion engine does. Such engines are very inefficient, as much of the energy exerted is converted to heat, not to mention the additional energy that's used just to propel the weight of the engine itself. If there was a way to reduce the heat generated, and/or create a smaller and/or lighter engine that significantly reduces its mass, you would significantly improve energy efficiency. (Example: When engine blocks moved from cast iron to aluminum, it not only reduced the weight of the engine, but also allowed quicker transfer of heat energy out of the engine. Significant improvement of engine efficiency.)

      This new engine has only one purpose: to spin a generator which charges the motor's batteries. With only that purpose in mind, this particular engine only has to run at a single speed to generate the RPM necessary to spin a generator. There's no need for lots of torque to propel the car forward at low speeds, plus one single RPM means that no drive train is necessary, plus one single RPM means that you can really simplify the design of the engine so that a minimal amount of cooling is required. All-in-all, you cut probably 90% off the weight of the engine, no longer require a radiator, and can transfer most of the energy generated directly to the generator, resulting in a much more efficient car.

      • by dougmc ( 70836 )

        I did read the article. I didn't watch the video.

        It could directly propel a vehicle if it wanted. It's probably as others have said -- it either takes a long time to spin up, or must always be run at full speed and/or power. Which could easily propel many vehicles, it's just poorly suited to cars -- *including* hybrids, I might add. (Though adding multiple smaller engines that are switched off as needed could help make it work for a hybrid car.)

        As for a minimal amount of cooling being needed, that's les

    • And what's this thing about "the engine is only suited for hybrid-electric vehicles, but that's okay. " ... what does THAT mean?

      Somehow I doubt this is going to pan out quite like they say it will.

      Well, my guess is that it has very little torque but high RPM, like a turbine. A piston engine has a torque curve like a distorted parabola. Where the vertical axis is torque and the horizontal axis is RPM. The wider the torque curve, the better performance the engine has, allowing you to "stay in gear" longer. A turbine tends to have a torque curve shaped more like a positive slope with an abrupt end. Requiring a different type of transmission.

      Energy is force over time, and engine power is measured as to

  • still waiting to see a working model that will run for a minute or two.

    also, they talk about reducing the weight by eliminating the transmission, but do they talk about the weight of the generators or electric motors?

  • And why do we never get to see one of these prototype rotating engines running?
  • *Needs an electric transmission. Still, the saving of 1000 pounds will add to the fuel savings. Sounds a lot like a gas turbine, although they claim better fuel economy.
  • by voss ( 52565 ) on Saturday April 09, 2011 @09:53AM (#35767448)

    Imagine an emergency generator 4 times more efficient than current models...

    Yes the military would be very much interested in generators that only require 1/4 as much fuel especially
    considering the cost transporting fuel to combat areas as would hospitals, the red cross, FEMA.

  •   and also rotary-based. They're claiming 125hp from a 10-inch, 66 cu-in, 100 lb engine

    http://www.regtech.com/Radmax_Technology/ [regtech.com]
    http://www.regtech.com/download/radmaxbrochure_trifold.pdf [regtech.com]

    • Angel Labs homepage [angellabsllc.com]
      MYT demonstration at SJSU [youtube.com] - youtube videos

      MYT is a swing-piston engine that can be scaled to basically any size you want, from lawnmowers to semi trailers. The 14" prototype is appropriate for replacing a large diesel engine.

      It was developed on a shoestring budget. At one point the prototype was running on diesel, but they switched it to run on compressed air for development and demonstration purposes.

      It's basically a swing-piston engine. The inventor doesn't want to sell out, and has be

  • by Anna Merikin ( 529843 ) on Saturday April 09, 2011 @10:32AM (#35767704) Journal

    The same video shown in the linked article is from UTube, uploaded Oct. 29, 2009.

    http://www.youtube.com/watch?v=uf_-IMgla34 [youtube.com]

    The concept of a detonation-wave engine is not new either. I remember reading about one in Popular Mechanics or one of its clones in the fifties or early sixties of the past century.

    Seems like PR fluff to me. And that's not new, either.

  • by John Hasler ( 414242 ) on Saturday April 09, 2011 @10:42AM (#35767756) Homepage
    RADIAL-FLOW WAVE ROTOR CONCEPTS, UNCONVENTIONAL DESIGNS AND APPLICATIONS [msu.edu]

    Some text to shut up the "lameness filter": No, it isn't anything like a Wankel.
    • I read the paper.

      I didn't see any claim of 60% efficiency. On page 4 first paragraph they claim a 34% improvement for small turbines, 25% for large turbines. Since diesels are already more efficient that turbines (for non-heat recovery turbines), that probably puts this in the same range, maybe a bit better, but not the factor of 3 that was claimed above.

      Since internal combustion engines are a multi-hundred billion dollar business, I'm very skeptical about any claim of a 3X improvement, especially one that

    • by 140Mandak262Jamuna ( 970587 ) on Saturday April 09, 2011 @01:50PM (#35769030) Journal
      It is basically a gas turbine engine. There is a centrifugal compressor. Followed by combustion chamber. Then a centrifugal turbine. Like a typical gas turbine the exhaust gases turn the turbine the is on the same shaft as a compressor. The compressor compresses the incoming air. The innovative thing is that the combustion chamber is made very compact and turned radially inward. Now a days gas turbines and jet engines use axial compressor making them long. And the combustion chamber is also arranged as long cylindrical cans along the axis. Here everything is radial. Compressor and turbine are centrifugal the chamber is radially inward.

      The gas turbine takes in air continuously and produces smooth power. This one has some kind of of ring that closes incoming air. Once it is spun and if the inlet is closed it is going to create very interesting airflow, and that is some how harnessed into self ignite the fuel air mixture. It will probably have a very narrow range of operating rpm. Starting would require us to spin this up to the operating rpm before it would produce power. So forget about low end torque or any such thing. It will produce power only at one speed and at one rate. In a gas turbine you could indirectly control speed/power by controlling the fuel flow rate. This one might not work at any other rpm or even fuel flow rate. Run it, charge the batteries and shut off, is going to be the mode of operation.

      So the efficiency is not going to be three fold increase. That claim comes by including the gains made by reducing the engine + transmission weight. But there is going to be electric motors and batteries added. So the claims are a little over stated. On the other hand it does not depend on any intricate seals like Wankel engines or other unknown things. Gas turbines are well known since WW II. So it is a good promising technology, but it is not likely to be any better than many other unusual engines people are fiddling with. A better picture: http://green.autoblog.com/2011/04/08/wave-disk-generator-engine-wave-of-future-video/ [autoblog.com]

  • They are using 15% as their baseline automotive number to inflate their ridiculous 3.5x efficiency claim. That should set off alarm bells right there. This is clearly an attempt to exaggerate the impact across the board here.

    I suspect the 60% efficiency number is purely theoretical and likely compounded by errors or even fabrications given the snake oil like claim.

    I don't see anything credible going on here.

    This appears to be some kind of micro-turbine, they best of which rarely top 30% efficiency.

    I certain

  • by 140Mandak262Jamuna ( 970587 ) on Saturday April 09, 2011 @11:09AM (#35767970) Journal
    The engine is optimized totally for efficiency. What is traded off is low end torque. Also response time is sacrificed. Present day automobile gas engines need to propel the car from rest, and also provide surge power to overtake other vehicles. Once you outsource these jobs to the electric motor and and produce constant power and allow a battery to absorb the excess power and use it when it is needed, the gas engine can do its only job, that is to convert chemical energy in the fuel into mechanical energy. Toyota Prius achieves its efficiency mostly by ditching the low end torque. All that regenerative braking etc make much smaller contribution. But even the Prius engine runs at various RPM depending on road speed.

    So despite the prof looking like Indiana Jones, what he is saying and showing is plausible. What is going to make or break this technology would be the weight of the battery pack needed to store all that extra energy to provide surge and low end torque. Prius has a very tiny battery, relatively, just enough to propel the car for about 2 miles. We might need a battery midway between Prius and Chevy Volt/Nissan Leaf for this technology to work. Of course, the fine tolerance manufacturing, durability of the engine and seals (the bugaboo of Wankel) and other issues might crop up.

    But the basic idea is plausible. Giving it one and half (guarded) thumbs up.

    • by grumpygrodyguy ( 603716 ) on Saturday April 09, 2011 @01:02PM (#35768716)

      What is going to make or break this technology would be the weight of the battery pack needed to store all that extra energy to provide surge and low end torque. Prius has a very tiny battery, relatively, just enough to propel the car for about 2 miles. We might need a battery midway between Prius and Chevy Volt/Nissan Leaf for this technology to work. Of course, the fine tolerance manufacturing, durability of the engine and seals (the bugaboo of Wankel) and other issues might crop up.

      But the basic idea is plausible. Giving it one and half (guarded) thumbs up.

      The article also mentioned shedding 1000lbs by using this motor.

      That's a free half-ton for more batteries which should cover the surge and low-end torque problems you mentioned.

  • by WindBourne ( 631190 ) on Saturday April 09, 2011 @04:40PM (#35770098) Journal
    This could be used on a number of products. RVs, Boats, Home Generators, and of course, hybrids. One very smart move on this would be to create a semi-truck with several of these, along with a small number of batteries. Quite the fuel savings.
  • by Nom du Keyboard ( 633989 ) on Saturday April 09, 2011 @06:52PM (#35770934)
    Let's revisit this when they actually have a working prototype car. And remember that these days internal combustion isn't as simple as just building an efficient engine. You have every kind of restriction from what fuel it can burn to what emissions it can emit to how much noise it can generate to what temperature range it must be operable over - not to mention what is it's operational lifetime? A competitive engine has a lot of conditions that it has to meet.
  • by George_Ou ( 849225 ) on Saturday April 09, 2011 @09:18PM (#35771506)
    The article mentions making a 25 kilowatt version of the prototype, but that translates to 33.5 horsepower. That's perfectly fine for human transportation (heck 1 hp should be able to propel a human to 60+ mph if the vehicle was aerodynamic and light), but Americans (or people of any wealthy nation) like to splurge on a massive car with a massive engine.

    This is indeed an engineering breakthrough, but what we need in conjunction with is either a change in human nature or some radical mandates on maximum vehicle weight. That obviously can't happen over night because no one wants to be in the smaller car when there is a collision. No one wants to unilaterally disarm on vehicle weight. What would need to happen is to have a max car and SUV size of say 4000 lbs and then reduce the maximum allowed weight by 100 lbs a year. Keep going until the maximum allowable car size is 500 lbs.

You will have many recoverable tape errors.

Working...