Do hybrids have any sense?

[Muchonen]

As amount of hybrids keep growing I am concerned about it's fuel efficiency. As far as I know from physics, every "energy change" (not sure about this phrase, I am not into mechanic English) is affiliated with loss of this energy (for heat etc.). So how it is possible that set of conventional fuel engine-generator-electical engine( transfer of energy: fuel-mechanical energy-electrical energy) is more efficient than one engine ( fuel-mechanical energy). I know that there are energy recovery systems but despite this, after discharged accumulators, that set efficiency should be lower than conventional engine.
So I have a conclusion that whole "eco" driving come from mental attitude and systems that "awards" you for your economic driving (Nissan Leaf with giving u leafs for eco drive).
So do you have any experience with hybrids and have an opinion about them?
I know that on short distances where u mostly use energy from accumulators it's obvious, but on longer distances and higher speeds it becomes more controversial.

[D-Type]

Put simply the power required at a given moment depends on the conditions. There is an optimum power unit for that condition and if you change the conditions you depart from the optimum. If you can save power from when you are producing it and don't need it and use it when you need it, then overall there is an increase in efficiency - even if the efficiency of the energy saving and energy recovery isn't very efficient.
Having said that, many 'eco' claims are false. Not because those making the claim are trying to deceive but because they are over-optimistic. To take a non motoring example, wind power is 'free' but the proponents forget that you still have to have a conventional power station for when the wind doesn't blow, or blows too strongly, so overall it is far from free. Then when you consider the overall energy saving of wind power, it comes down to the accuracy of weather forecasting so you don't start up the alternative power too soon and keep it running too long when unsuitable weather happens.

[Rollo]

As amount of hybrids keep growing I am concerned about it's fuel efficiency. As far as I know from physics, every "energy change" (not sure about this phrase, I am not into mechanic English) is affiliated with loss of this energy (for heat etc.). So how it is possible that set of conventional fuel engine-generator-electical engine( transfer of energy: fuel-mechanical energy-electrical energy) is more efficient than one engine ( fuel-mechanical energy). I know that there are energy recovery systems but despite this, after discharged accumulators, that set efficiency should be lower than conventional engine.


Let me lead you through this with a series of questions.

When does an Internal Combustion Engine produce most torque?
When does an Internal Combustion Engine produce most power?
When does an electric engine produce most torque?
When does an electric engine produce most power?
What are you doing with the power produced from an Internal Combustion Engine at idle?
What are you doing with the power produced from in a hybrid system at idle?
What are you doing with the extra capacity to produce power from an Internal Combustion Engine at idle at anything less than peak?

You are quite correct that in every change of energy from one form to another, there is a step down in the total energy of the system and the rest is wasted as heat. The reason as to why a Prius can get a combined cycle of 4.9L/100km as opposed to a Yaris at 5.8L/100km out of the same 1NZ-FE engine, is contained within those questions.

[Jag_Warrior]

As amount of hybrids keep growing I am concerned about it's fuel efficiency. As far as I know from physics, every "energy change" (not sure about this phrase, I am not into mechanic English) is affiliated with loss of this energy (for heat etc.). So how it is possible that set of conventional fuel engine-generator-electical engine( transfer of energy: fuel-mechanical energy-electrical energy) is more efficient than one engine ( fuel-mechanical energy). I know that there are energy recovery systems but despite this, after discharged accumulators, that set efficiency should be lower than conventional engine.
So I have a conclusion that whole "eco" driving come from mental attitude and systems that "awards" you for your economic driving (Nissan Leaf with giving u leafs for eco drive).
So do you have any experience with hybrids and have an opinion about them?
I know that on short distances where u mostly use energy from accumulators it's obvious, but on longer distances and higher speeds it becomes more controversial.

Very interesting set of questions.

If I began looking at the value of a hybrid for a (normal) passenger car vs a non-hybrid, I would probably look at it from the cost standpoint of total $ (or Euros)/distance driven and also compare the total cost of ownership of a hybrid vs. a non-hybrid. As fuel oil prices rise and fall, I guess the comparison would become rather dynamic. But still, I think one could come up with an average over, say a five year time period.

[Rollo]

If I began looking at the value of a hybrid for a (normal) passenger car vs a non-hybrid, I would probably look at it from the cost standpoint of total $ (or Euros)/distance driven and also compare the total cost of ownership of a hybrid vs. a non-hybrid. As fuel oil prices rise and fall, I guess the comparison would become rather dynamic. But still, I think one could come up with an average over, say a five year time period.

That question is easy... buy a normal car.

In Australia at least where diesel tends to be more expensive (but you use less of it) and diesel cars tend to be more expensive, the break even point to recover those initial costs of the car tends to be about 5 years depending on the model.

[airshifter]

There is a website run by the EPA that breaks it down fairly well, and allows you to add variables in fuel costs, percentages of urban driving, etc. That way you can customize the costs comparison based on your driving reality. I don't think it allows punching in electricity costs though, so adding a plug in hybrid to the mix will require some math on your part.

http://www.fueleconomy.gov/feg/hybrids.jsp


There are a few cases where hybrids can pay for themselves in fuel savings very quickly for most drivers. As an example, the Lincoln MXZ is the same retail price in conventional and hybrid styles. Though an exception to the rule, some hybrid variants aren't all that much higher in price these days.