Electric and thermal cars: well to wheel assessments

[Christophe]

What is the overall result of an electric car compared to that equipped with a heat engine? The electric car is it so much cleaner as claimed by manufacturers and journalists (sorely lacking in analysis for some time ...). What are the most energy-unfavorable steps for each type of propulsion?

Here are some answers.

The figures are to be taken as an average. The output of a refinery varying according to its age and the quality of the crude just like that of a power plant, it would be very difficult to make an assessment of extreme precision ... or it would have to be done on a case by case basis .

These figures are therefore to be taken as trends.



Some explanations and details from the author:

this is a small table that I made by gleaning and cross-checking a certain number of information on the net. everyone can find these values. each figure is questionable in itself since there is not a single value for a single condition but the orders of magnitude are there.
for example the heat engine can have yields ranging from less than 15% to more than 30% depending on the technology and especially the range of use.
I think that the values ​​in this table are rather optimistic for the thermal and rather pessimistic for the electric but it made me laugh to fall on the same value and then it allows to put off the controversies between the pro VE and the pro thermal.

Personally, the big advantage that I see in EV is not on its efficiency but on the fact that it can use a primary energy source other than oil in this example because electricity is only a vector energy and not a primary energy. moreover and more generally, I am convinced that precisely, for these qualities of "versatility", electricity is an energy vector of the future. (it is also already widely used)

For more reflections:
Transportation-electric / electric-car-limits-physical-and-balance-global-t6294.html
new-transport / car-the-future-of-t6803.html
Transportation-electric / le-for-and-against-the-car-of-electric-t7004.html
new-transport / balance-well-to-the-wheel-of-a-car-h2-diesel-and-gas-t6093.html

[jlt22]

The opinion of an economics professor on the electric car:

http://www.lesechos.fr/entreprises-sect ... 646560.htm

A question that comes to mind as the weather cools:
what is the heating mode in an electric car?

In a thermal car, we recover the calories generated by combustion, and which in any case would be rejected outside.

[chatelot16]

3 solution:
1) big sweater and no heating
2) electrical resistance: energetically bad but light
3) reversible air conditioning: better energetically but heavier, and to hang around all year even when the heating is useless: it is quite possible that all in all the simple resistance is the best

it gives to think about the interest of the 100% electric car: I prefer a hybrid with small heat engine and large battery: we can use the heat engine when heating is needed ... in summer we can try to run at 100% electricity without being afraid of the end of electric autonomy ... too bad the current hybrid have too small batteries

[dirk pitt]

on most of the existing electric vehicles (at least the old generation PSA and renault) the heating is .... with gasoline or diesel by a small boiler catalyzes Webasto like the heating of cabins of heavy-weight.
and yes, you must not be a fundamentalist (I don't like fundamentalists) and not use petroleum at all.
the heat pump solution is surely better.

[Christophe]

You forgot the 4th that Citro uses in winter (it seems to me).

4) The backup burner.

There is a well-known brand that sells these "micro boilers" for Nordic heavy goods vehicles, in particular: webasto. I believe that the equivalent consumption is around 1L / 100km ... Citro will specify.

We said it again: the interest of the electric car can be twofold:
a) energy: interesting if the source of supply is 100% renewable and sustainable
b) environmentally: zero discharges at vehicle level, limited socio-economic cost of large cities ... it still has to become widespread in the city. But for the city, it is the model of the individual car that must be reviewed and an electric bike equipped with a remoque would be sufficient in many cases ...

This is why I am not sure that hybrids in the city is the solution: their mass does not play in their favor ...

But we are not going to redo the debates on the 4 subjects mentioned above ...
This topic was just a "sticky note".

[chatelot16]

yes, i forgot the best solution! and in addition I know it, I have a few recovered on old buses that I used as auxiliary heating: it works just as well with petrol, oil, or fuel oil: it's light for a big power !

[Alain G]

In an electric car the heating is also electric, it certainly decreases the range but in winter the thermal already consumes at least 20% more. Not to mention the pollution multiplied by 100 until the catalyst has reached its temperature.

So heating is a false debate to denigrate the electric!

[dirk pitt]

In an electric car the heating is also electric,

do you read what others write ??

[Christophe]

In an electric car the heating is also electric, it certainly decreases the range but in winter the thermal already consumes at least 20% more. Not to mention the pollution multiplied by 100 until the catalyst has reached its temperature.

So heating is a false debate to denigrate the electric!

Generally agree with you but there, not at all ... it is not to denigrate but to understand and explain.

How do you want to heat a car that moves in the cold (and which is a real "thermal bridge of emissivity") over several hours with a few electric kWh? Especially since the batteries do not like the cold ...

It's simple: Citro consumes 1L / 100km (to be confirmed) just for heating, or 10kWh to compare to its 12kWh of battery capacity ...

[Alain G]

In an electric car the heating is also electric, it certainly decreases the range but in winter the thermal already consumes at least 20% more. Not to mention the pollution multiplied by 100 until the catalyst has reached its temperature.

So heating is a false debate to denigrate the electric!

Generally agree with you but there, not at all ... it is not to denigrate but to understand and explain.

How do you want to heat a car that moves in the cold (and which is a real "thermal bridge of emissivity") over several hours with a few electric kWh? Especially since the batteries do not like the cold ...

It's simple: Citro consumes 1L / 100km (to be confirmed) just for heating, or 10kWh to compare to its 12kWh of battery capacity ...

At the risk of repeating myself, the battery compartment is insulated and also heated so there is no real loss at this level especially since only a few watts can maintain an acceptable operating temperature. In addition, some batteries are less affected by this phenomenon.

The problem lies in the frequency of use of the car, so little used, there is overconsumption due to the heating of the batteries but if there is the possibility of connection at home and at work for example, I do not see any problem.

This is why I recommend the hybrid with electric priority.