The diagram depicts the process of generating electricity in a hydroelectric power station.
Overall, the hydroelectric power station works differently at day and night. At day, water flows from a river to reach the national grid, and there is a flow of water from a low-level reservoir to a high-level one.
In detail, at day, water moves from the river to the high-level reservoir where a dam is built on. Water there continues to flow to reversible turbines at the power station. After moving to such turbines, two steps happen simultaneously. The first one is that an amount of water moves through these turbines to the low-level reservoir. And the second one is that the remaining water is pushed to a generator which is operated by reversible turbines. Here electricity is generated and moves to power lines. The process culminates when electricity reaches the national grid.
At night, the amount of water in the low-level reservoir is pumped into the high-level one due to reversible turbines.

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The diagram depicts the process of generating electricity in a hydroelectric power station. The water used comes from a river and is collected in a high-level reservoir and held there by a dam.

Overall, the [ 1] hydroelectric power station works differently at day and night processes at the power station are the reverse of each other. At day, water flows from a river to reach the national grid, and there is a flow of water from a low-level reservoir to a high-level one.[ 2]

In detail, at During the day, the dam inlet is open and water moves from the river to the high-level reservoir where a dam is built on. Water there continues is allowed to flow to through reversible turbines at the power station. Since the power station is at a lower altitude than the reservoir, gravity drives the flow of water. The fast flow of water causes the turbine blades to spin and generate electricity. The electricity is then transferred through power line to the national power grid. After moving to such turbines, two steps happen simultaneously. The first one is that an amount of water moves through these turbines to the low-level reservoir. And the second one is that the remaining water is pushed to a generator which is operated by reversible turbines. Here electricity is generated and moves to power lines. The process culminates when electricity reaches the national grid.

At night, when the demand for electricity is low, the dam inlet is closed, and the generation of power stops. Instead, the amount of water in the low-level reservoir is pumped back into the high-level one due to through the reversible turbines.

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[ 1]: Avoid repeating words/phrases in such close proximity.

[ 2]: Water does not flow to the grid! And it flows the other way during the day.

I usually have little knowledge about some kinds of processes. So this type is the most challenging for me.

Thank you very much!!!

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Nhật Bình

I usually have [ 1] little knowledge about some various kinds of processes, but So this type is the most one was quite challenging for me.

[ 1]: Note that "little knowledge" means almost no knowledge! You should say "a little knowledge" or "some knowledge" instead.

Yes, that task was harder than average.

teechr"little knowledge" means almost no knowledge

'Have no knowledge' is the most correct.^^

Honestly, when dealing with this type, I only describe what I can see on the illustration without knowing whether what I am writing is factual.^^

A simple thing to do is make the paragraphs clearer by leaving a space between them.

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Nhật Bình I only describe what I can see on the illustration

But on the diagram, it is electricity that flows into the national grid, not water. Water is circulated between the upper reservoir and lower reservoir, as shown.

The power that drives the turbines is actually gravity. The earth's gravity causes the water to flow downhill from the upper to the lower levels. The force of the flowing water turns the turbines, which makes electrical current. The need for electricity is higher during the day than at night.

The river keeps the upper reservoir filled.

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AlpheccaStarsThat volume is much, much smaller. Can you think of the reason?

It's beyond my hen. I'm 16 years old, and I haven't learnt about it.^^

I took that part out and replaced it with the video.

It takes energy to pump the water uphill, doesn't it?

Suppose that you used the electricity generated during the day to charge some batteries. Then you used those batteries to run a motor that pumped water up from the lower to the upper reservoir at night.

Do you think the batteries last long enough to return all the water back to the top, so the next day that same water could be used to recharge the batteries again?



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