Power consumption question?

Sorry if this is stupid, but I have always been curious about this. Since mains generators run constantly (or I assume they do...) does it matter whether or not you leave you electrical appliances on? Like people who say turn the lights off when you leave a room so that you save power. But the generators still go if your lights are on or not, so you're not really wasting energy, are you?

sort by: active | newest | oldest
verence6 years ago
If you have your own power supply (wind, water, solar etc.) and you don't store unused power in batteries, you are right. What you don't use at the moment is lost.

For a nation wide (or even international as in Europe) power grid, the situation is much different.

1. The generators do NOT run constantly. Whole power plants get switched on and off during the day to adapt the power generation to the demand.
2. Unused available electricity is stored in different ways and can be recalled when needed without burning up more oil, coal etc.
3. Even a running generator does not generate an amount X of power all the time. In fact, a generator will only produce as much electricity as is used. (Where should the unused current go, anyway?)

So, yes, it does matter, if you switch unused stuff off or not.

2. Unused available electricity is stored in different ways and can be recalled when needed without burning up more oil, coal etc.


Not so much really, I can think of a few pumped storage systems, but that's about it. There's a fuel cell trial or two as well.

We really NEED storage systems.

Steve
2. Unused available electricity is stored in different ways and can be recalled when needed without burning up more oil, coal etc.

they were stored in batteries long ago. now they run proportionally to power demand
iceng ARJOON6 years ago
Also, lets not forget storage batteries are only 50% efficient at best.

It takes twice ( 2X ) as much energy to charge a battery as you get ( 1X ) out of it later.

Confusing ?

How about, you can only get back 1/2 of the energy you store in a battery.

Even vacuum flywheel storage can do better.

A
Yes, but with vacuum flywheel storage, you can't turn corners.....
Mount the wheel in horizontally.
I recall your country had some flywheel busses and the passengers were unnerved that the bus would rev the engine when approaching a stop.
Not at the power levels we're talking about in grid systems they don't, and never have. This is one of the biggest pumped storage systems in the world

It can only supply its rated, 1.3GW output for five hours. Though there are bigger ones, Dinorwig is the world's fastest, and can go from spinning in air, on standby, to full 1.3 GW, in TWELVE SECONDS.

I've been there, when its been turned on like that. Its something I won't ever forget.

Steve
True, we need more storage system, especially, when whole countries want to go 'green' and get all their electricity from wind, sun waves etc. Too bad that the sun doesn't shine at night, when we need the most light ;-)

It's true, the wont fire up a nuclear power plan just because you leave a light on or two, but if a few thousand people leave their appliances run unused, that might make a difference.

Anyway, I don't know where 7654321 lives, but I have to pay for electricity. So, it will not only be wasting energy , but it's wasting your (or your parents) money.
Nuclear stations are, as we know, buggers to turn down....So they were supposed to provide the baseload, always running flat out, and, at night, pump up Dinorwig to handle peak loads in the day time.
iceng6 years ago
If a single gasoline to electric generator is running while fully loaded it will use more gasoline then when it is running without any electrical load.

Confusing ?

Two identical generators A & B with full gas tanks.
Generator A will power 1 old style 60W lamp for a 60 Watt total load.
Generator B will power 5 old style 100W lamps for a 500 Watt total load.
Start both generators and walk away..

Which generator will run the longest ?

A
lemonie6 years ago

If they're on then they are using energy.
If they are not being used for a useful purpose then the energy they use is wasted.

L