Comment on Power is not energy: why the difference matters [Technology Connections]
werefreeatlast@lemmy.world 1 week ago
I haven’t watched it but its really simple. If you receive 1kW within 1hr and you compare that amount of power to 1kW over one second things are much different. The first is like a nice heater in a cold winter night…nice steady energy, a little bit of power. The second is like hell hole, tons of energy but still only a little bit of power. Power is the ability to do work or simply move things. Energy is the total amount of moving things regardless of the actual power used. So if you toasted a toast, that was a lot of power delivered quickly, but you could also do all that work slowly over centuries and eventually end up with the same molecular arrangement using the same amount of energy.
theherk@lemmy.world 1 week ago
“1kW within 1hr” isn’t power. That’s energy.
“nice steady energy”? You mean nice steady power, right?
“The second is like hell hole, tons of energy but still only a little bit of power.” No. They are both precisely the same energy.
“So if you toasted a toast, that was a lot of power delivered quickly.” No. That is a lot of energy delivered quickly.
I typically wouldn’t be pedantic about this, except that this is precisely the point the video is making. These two unit types are often confused.
solbear@slrpnk.net 1 week ago
The watt is always power, not energy. I’m assuming OP here got some prepositions mixed up and meant 1 kW delivered for 1 hr. That amounts to an energy of 1 kWh.
No, they are the same power. The energy in the case where 1 kW of power is delivered for 1 hour is 1 kWh. The energy in the case of 1 kW delivered for 1 s is about 0.28 Wh.
If instead 1 kWh was transferred over the course of 1 hour, that is an average power of 1 kW (but does not have to be uniform, without more information we can’t know the power profile). If 1 kWh is transferred over the course of 1 s, that is an average power of 3.6 MW which is the example I think OP was getting at (ref. hell hole comment).