Featured Toyota Says You’ve Been Misled—Most “Hybrids” Aren’t Really Hybrids

Discussion in 'Prius, Hybrid, EV and Alt-Fuel News' started by Tideland Prius, Oct 29, 2025.

  1. bisco

    bisco cookie crumbler

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    it's the internet, we have to argue :cool:
     
  2. Trollbait

    Trollbait It's a D&D thing

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    You were talking climate impact, that involves carbon emissions. A study from several years back(was discussed here) calculated the 'best bang for the buck' in terms battery capacity for reducing carbon emissions from the personal vehicle fleet. Building a bunch of diesel mild hybrids does more for that reduction than a few full hybrids and plug ins.
    With the battery from a Rav4 PHV, we can replace...
    • 1 ICE SUV with a PHEV
    • 18 ICE SUVs with full hybrids
    • 90 ICE SUVs with diesel mild hybrids
    A single PHEV will reduce an individual's carbon emissions by a lot, but leaves a lot of straight ICE cars on the road. More hybrids means even greater carbon reductions over the entire fleet.

    Aside, how does the commute cost less than a BEV when even the bZ4X is more efficient?
     
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  3. Isaac Zachary

    Isaac Zachary Senior Member

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    Where can I get my diesel mild hybrid please? :D

    Hopefully a small sedan or hatchback with a stick-shift.
     
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  4. hill

    hill High Fiber Member

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    High compression Diesel is not built to be start/stopped. It must run constantly to be efficient. In theory a constantly running diesel w/ battery backup would work - but that's countering what we think of as a hybrid.
    .
     
    #44 hill, Nov 4, 2025 at 11:43 PM
    Last edited: Nov 5, 2025 at 9:08 AM
  5. dbstoo

    dbstoo Senior Member

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    There was a standards based list available a while back. It specified the various types. There were:
    series hybrids
    parallel hybrids
    series/parallel hybrids
    mild hybrids

    The Mild hybrids are often set up to use a hefty battery to start and stop the engine.
     
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  6. Isaac Zachary

    Isaac Zachary Senior Member

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    I'm not sure that's true.

    I used to hypermile my 1985 VW Golf diesel with something like a 23:1 compression ratio, and it seemed to work pretty well, stopping the engine and then starting it, either with the starter or by the car's momentum.
     
  7. Trollbait

    Trollbait It's a D&D thing

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    Better let Toyota know then, since that's what their Hilux mild hybrid does.

    All engines need to run at a constant point for best efficiency. That does preclude them from being stopped and started again. This sounds like a rationalization to continue the practice of idling diesels, which is no longer the case.
     
  8. bwilson4web

    bwilson4web BMW i3 and Model 3

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    If I wanted to show Toyota how to do it:
    • Start with a Prius Prime
    • Replace all ICE with equivalent weight battery
    • Hack/replace control laws transaxle controller
    But why bother when used Teslas are a better base.

    Bob Wilson
     
  9. hill

    hill High Fiber Member

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    Diesel nowadays under CARB rules - modernly is a FAR cry from mid 80's 1.6 liter 4 banger (compared to modern dual battery 6½+ L) . Old little diesel engine fuel pumps pressure could easily be under 4K psi. Emissions standards now require better atomization of fuel, requiring 10Kpsi pumps.
    To make them as clean or cleaner than a gasser - there's (dpf) diesel particulate filtering, selective catalytic reduction (scr) systems, (def) diesel exhaust fluid .... & like gassers, an EGR. Start stop cycles on diesels quickly load up a DPF, which sends the system into a regeneration cycle .... & if that's shut off by starting stopping (regularly), the dpf WILL load up to the point where modern diesels will go into a power limiting cycle (limp mode) that can reduce top speed to easily mean under 40 mph. Pray to God you're not on a hill pulling a trailer under those conditions.
    That makes one wonder - could the Helix meet CARB compliance? I suppose possibly. Those are just some of the theoretical DIESEL/CARB issues.
    https://carfast.express/en/news/auto/toyota-hilux-in-the-usa-everything-you-need-to-know-about-importing
    Yea - so there you have it. So much for your modern carb diesel / stop/start ever coming to fruition in the states. & speaking of tougher standards - last couple winters (for a week or 2) we hit temps below -20°f & a couple of those days were below -30°f. Try & pour diesel #2 at those temps - much less force it through a 2 or even a 10 micron fuel filter (necessary for high pressure 10,000 PSI pumps modernly) . Fortunately we have one of those VERY rare stations maybe 10 miles away that sells #1 fuel (extra 90¢/gallon) that's closer to kerosene which doesn't solidify into wax the way #2 will (w/out pouring in enough anti-gel treatment). Fuel viscosity concerns start around 20°f & progressively worsen w/ Sub-0°f temps).
    But yeah we ARE a creative species & one might suppose that if there's a will - there's a way.
     
    #49 hill, Nov 5, 2025 at 10:09 AM
    Last edited: Nov 5, 2025 at 11:30 AM
  10. Rmay635703

    Rmay635703 Senior Member

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    Once warm naturally aspirated diesels restart much more easily than a gas engine firing on the first compression stroke.

    make naturally aspirated diesel hybrids with the hybrid part to make up for power/acceleration and you have a much more reliable and efficient all weather offering