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by nightski 870 days ago
In principle I really like it, use gas for long distance and electric for the other 90%. However aren't you really just getting the worst of both worlds? Under-powered gas engine and limited range ev? Wouldn't it weigh a lot more and have twice as many parts to break down? All the maintenance of a gas engine with the additional cost of a battery/electric?
10 comments

I have a hybrid highlander and love it.

The reason they are efficient is something like this:

A cars engines efficiency/fuel economy is constrained by its max output. Ie when you have an engine capable of very rapid acceleration, that engine is going to be too big across all other scenarios - ie two cars of the same weight going the same speed , the one with the bigger engine will consume more fuel.

The hybrid lets you take advantage of this in two ways. First it allows you to have a smaller engine because the electric motors kick in when you need the acceleration. So it lets you get away with a smaller engine that is more than enough for your driving and that gives you efficiency.

Then it also uses the fact that even the smaller engine is still oversized for things like coasting or going steady so it uses the extra engine output to charge the battery at the right times. Regenerative breaking is another efficiency play

Curious what will happen to the battery over time but for the past few years the hybrid highlander is great.

> two cars of the same weight going the same speed , the one with the bigger engine will consume more fuel.

Generally. But that bigger engine might be producing more power at a lower RPM and there might be some cases where the difference isn't as noticable.

They usually turn out more reliable (if built right) because you can remove the transmission entirely, which is a major complicated piece of mechanical engineering that is prone to failure.
They also get to run the engine at a lower duty cycle while it is warming up, which is a big source of wear and tear for a gas engine. They also never have to run a rich mixture because the power gap is made up for by the electric motor.
They are more reliable because Toyota sells a large fraction of the hybrids. Non-Toyota hybrids are less reliable than both gasoline cars and EV's. Maybe that's circular because a large fraction of the non-Toyota hybrids are Stellantis...
The designs of some hybrids are able to remove a lot of parts that normal ICE-only cars have.

The design of most Toyota hybrids is quite simple, there are two electric motors and one gasoline engine coupled by a simple planetary gear set. This eliminates the need for a mechanical transmission -- varied wheel speed is accomplished by simply varying the relative speeds of the electric motors. Contrary to a popular misconception, there is no mechanical cone-and-belt CVT in Toyota hybrids, like people might be familiar with in other CVTs. Also, because the engine is linked to the drive motors, this eliminates the need for a starter motor. And because all of the engine accessories are electric on most Toyota hybrids (because they need to operate when the engine is off) there is no accessory belt.

These components (drive belts, transmissions, starter motors) aren't uncommon issues in ICE-only vehicles, so this does translate to improved reliability and lower maintenance.

Yes as sibling said they are often more reliable.

Also keep in mind that the electric tends to handle low speed movement which it's just great at (instant torque), while the gas engines tend to handle highway / steady state driving which they are just great at. And overall they are each getting less usage than if they were the only powertrain.

A plugin hybrid can have a smaller range battery (as long as the range meets your daily driving needs). Ideally it would give you at least 60 - 80 mile per day range, not the 20 something miles that a lot of them provide.

A full electric on the other hand, needs a very huge battery as it need to give you about 300 mile range, to cover the edge cases. That is a lot of battery weight (and expense) you are carrying around. So the tradeoff is do you want to lug around a huge battery that you will mostly not use, or lug around a gas engine that you will mostly not use? About an equal tradeoff (esp. since the gas engine only needs to be enough HP to maintain cruising speed, acceleration can be handled by the battery, or have it set up as a serial hybrid).

Personally I'd rather have the gas engine as my range extender, instead of the larger battery, since I can quickly fuel up in about 3 minutes vs. 20 - 30 at a minimum. But once battery tech improves and recharge times are in the 10 minute range, I'd say that would be the end of gas engines.

These hybrids should be 100m EV range, that is plenty for most trips. The RAV4 Prime gets about 42m from each charge, which is a bit short for my commute but cuts by gas consumption by a whole lot.

There's nothing under-powered about the gas engine. F-150 daily drivers may cringe, but that's a cultural problem not a problem with the vehicle.

That's pretty good for the Rav4. From what I can tell though the highlander only has a 5 mile range at a max of 25 mph when in EV only mode. It's very limited and clearly you are meant to run the gas engine most of the time along side the electric motor.

Call it a cultural problem if you want, but a F-150 is damn useful even if it is not utilized all the time. When you do need it though, it's there and ready to work. There is a reason it's the best selling car in America.

I call it a cultural problem because in forums I am active in EVs are derided as some sort of crazy plot to take away our freedom. I totally agree a truck is useful to have.
Hybrids are very reliable, especially plug-ins like the Volt that essentially have redundancy and will operate with one of the engines completely disabled. Generally speaking it’s far less wear and tear to drive an electric motor with a generator than it is to have a crankshaft / belts / pulleys / transmission / air driven throttle / complex cooling loops / etc, even with the additional parts.
The new Prius puts down horsepower on par with a Civic SI and does 0-60 in 6.4 seconds. I don't think "underpowered" is a given. Turbohybrids have been the state of the art for F1 racing for a decade now too.
> Turbohybrids have been the state of the art for F1 racing for a decade now too.

I don't think "state of the art" is the word when there's no variability or development because that is the engine style mandated by regulations for that time.

Studies show that there's enough studies to claim any type of car is more reliable, usually by (not) adding in people who complain about bluetooth etc. Or lumping expensive EV sports car tyres in with everyone else
Depends on your needs, right? I prefer an underpowered car with excellent fuel economy, so that's a benefit.

99% of my daily local trips are under 40 miles, so short range isn't a factor.

I mean, that's just me, but for me it's a near-perfect fit.

Until batteries and chargers get better, anyway.