Electrical and Computer Engineering

1984 readers

2 users here now

Electrical and computer engineering (ECE) community, for professionals and learners. Discuss ECE related topics here, for instance digital design, signal processing, circuit analysis, electromagnetics, microelectronics, power electronics, RF electronics, etc.

founded 2 years ago

MODERATORS

phreedf@lemmy.world

dragontamer@lemmy.world

A hypothetical question about electricity (lemmy.ca)

submitted 1 week ago by SpookyLights@lemmy.ca to c/ece@lemmy.world

4 comments fedilink hide all child comments

Hi! So a question just popped into my mind and I need to know. Ok, so let's say we have a hypothetical power source that's some sort of self-sustaining reaction or process. And let's just say that once we start it, there's no way of shutting/slowing it down.

The largest capacity power plant on the globe is the Three Gorges Dam with an output of 22,500 MW. Let's say our hypothetical power source also puts out 22,500 MW. Let's also say that our hypothetical power source also has the potential to go into a sort of "meltdown," and when in this condition, our hypothetical power source has the potential to double it's electrical production to 45,000 MW for a brief time.

So my question is this: If a worst case scenario occurred and the power plant that contained our hypothetical power source was disconnected from the grid, what would the best way to "burn off" all of that electricity that now had no where to go? Thank you for humoring me :)

you are viewing a single comment's thread
view the rest of the comments

[–] ArbitraryValue@sh.itjust.works 5 points 1 week ago* (last edited 1 week ago) (1 children)

Converting electrical energy into heat is trivial. The cooling towers associated with nuclear power plants exist for the purpose of dissipating waste heat by evaporating water and/or heating air. (But in the case of nuclear reactors, they're dissipating heat energy that was never converted into electrical energy.) Pumping in cold water from a lake or reservoir, heating it, and pumping it back out can also be used for the same purpose.

Water can absorb relatively large amounts of energy without much change in temperature. If you're thinking specifically of a hydroelectric dam, consider that simply letting the water flow through without turning turbines would cause most of the potential energy in that water to be converted into heat by default. Water at the bottom of a waterfall is warmer (by only about a tenth of a degree for Niagara falls) than water at the top.

[–] Limonene@lemmy.world 1 points 1 week ago

This is kinda how nuclear reactors are anyway. You can't just shut them down instantly. The fuel rods produce energy for a while after the control rods are inserted, so they have to have dummy loads for them. I think it's usually just an emergency water supply that they can boil off.

I know some turbine systems have resistive loads that can be used to stop the turbine quickly in an emergency, but they are only meant to be used for an instant before they overheat.