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Why would an electricity system pump water uphill?

Water raised to an upper reservoir stores energy that can later be recovered through a turbine and generator. Pumped storage shifts electricity use across time, with losses between charging and discharge.

12–15 min

Questions you could explore

  • What is the difference between how much energy a reservoir stores and how quickly it can release it?
  • Why is the return smaller than the energy used to pump?

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How can a heat pump deliver more heat than its electricity input?

Energy4–5 minA heating device seems to promise something impossible when its heat output exceeds the electricity it uses. A heat pump's energy account includes another input: heat moved from its surroundings.

Energy

How does a photovoltaic cell turn light into electricity?

A solar cell can generate electricity without a turbine or other moving machinery. Light interacting with a semiconductor starts the process, but separating and collecting the resulting charges is what makes electrical output possible.

4–5 min

How does a photovoltaic cell turn light into electricity?

Energy4–5 minA solar cell can generate electricity without a turbine or other moving machinery. Light interacting with a semiconductor starts the process, but separating and collecting the resulting charges is what makes electrical output possible.

How does a wind turbine turn moving air into electricity?

Energy3–5 minA turbine's blades are only the visible beginning of the journey from wind to electricity. Their rotation drives a generator, though the machinery connecting those parts differs between turbine designs.

Why would an electricity system pump water uphill? | Speech Topic | speaking.app