are electric cars good or bad for the environment?

[Steve]

Disclaimer: I am not an engineer of any sort.

I have been watching the debate over electric vehicles, specifically whether
or not they are actually benefical to the envirnoment, presuming they are
charged using electricity from coal plants. My question is more about the
plants themselves, and how much electricity that is generated by them is
actually consumed.

When I turn off a light bulb in my house, does the coal-fired generator that
provides my electricity suddenly see that it needs to burn less coal? I
doubt it. I am beginning to surmise that a plant must generate more
electricity than is actually used. But, where does this excess juice go?
And since power rates are lower at night, does this mean that even more of
the generated power goes unused then?

All of this leads me to a belief that electric cars, especially those
charged at night, are not responsible for the burning of any additional
coal, due to the (presumed by me) over-production that it must maintain.
They just help to make use of a higher percentage of the electricity that is
being generated anyway.

Am I off-base here? Someone please put an authoritative spin on all of
this!

Thanks much,
Steve

 

[James Sweet]

Disclaimer: I am not an engineer of any sort.

I have been watching the debate over electric vehicles, specifically whether
or not they are actually benefical to the envirnoment, presuming they are
charged using electricity from coal plants. My question is more about the
plants themselves, and how much electricity that is generated by them is
actually consumed.

When I turn off a light bulb in my house, does the coal-fired generator that
provides my electricity suddenly see that it needs to burn less coal? I
doubt it. I am beginning to surmise that a plant must generate more
electricity than is actually used. But, where does this excess juice go?
And since power rates are lower at night, does this mean that even more of
the generated power goes unused then?

All of this leads me to a belief that electric cars, especially those
charged at night, are not responsible for the burning of any additional
coal, due to the (presumed by me) over-production that it must maintain.
They just help to make use of a higher percentage of the electricity that is
being generated anyway.

Am I off-base here? Someone please put an authoritative spin on all of
this!

Thanks much,
Steve

Turning off a single light bulb is far too small a load to have a
measurable effect on generator output. The amount of fuel consumed to
drive the generator does vary with load however, typically being much
greater during so called peak hours during the day and falling off at
night. As someone else said, generator efficiency does drop as the
output falls below 100%, so there is some effort to shift loads to
off-peak hours where there is excess capacity.

As for electric cars, the debate has raged on since the beginning, and
there are far too many factors to say one way or the other with
certainty. On one hand a large scale power generation plant is far more
efficient at converting fuel to energy than individual combustion
engines in cars. On another hand, electric cars tend to require
considerably more energy to manufacture, there is loss in every step of
transmitting and transforming the power, and you have the issue of
recycling the batteries when they wear out.

My opinion is that electric cars are not an end-all solution to our
transportation problems, but they are ideal in certain situations where
they fill a niche, and they drive the development of technology that
will be useful in one form or another in the future. Over here where a
large portion of our power comes from hydro, they make reasonable sense.
95% of my driving is the 8 mile commute to work and picking up groceries
and such around town. I wouldn't get rid of my gasoline car, but even
something with a 20 mile range between overnight (off-peak) charges
would cover the vast majority of the driving I do. Removing local
sources of air pollution in congested city streets is a good thing.

 

[Bill]

Well you can get an electric vehicle and charge it with solar electricity.

That bypasses the greedy big energy companies, so a good thing in my book!


"Steve" wrote in message