Hydroelectric generation and energy question?

In summary, the task is to estimate the annual average rate of water flow needed for hydroelectric generation in an average home, taking into account factors such as a 90% efficiency and a lake level 20 m above the generator. This involves converting the potential energy stored in the water to kinetic energy through a turbine. Using the average household electricity usage of 8,900 kWh per year, the density of water, and the given information, one can calculate the necessary flow rate.
  • #1
bohobelle
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0

Homework Statement


Imagine that all the electricity used in an average home comes from hydroelectric generation. Your task is to estimate the annual average rate at which water would need to flow to generate the power for that home (gallons per minute or cubic meters per second). Make your estimates using a hydro system that is 90% efficient and in which the lake level is 20 m above the generator. Hydro plants work by converting GPE stored in the water to KE as it falls and turns a turbine.
The average household uses 8,900 kWh of electricity each year or 32,040,000,000 J per year.
The desnity of water is 1000 km/m^3, and the lake is 20m above the generator. Hydro plants convert GPE stored in water to KE as it falls and turns a turbine.

Homework Equations





The Attempt at a Solution


I honestly have no idea where to start with this equation. My professor has never gone over anything remotely like this in class, so I honestly do not know where to start!
 
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  • #2
bohobelle said:

Homework Statement


Imagine that all the electricity used in an average home comes from hydroelectric generation. Your task is to estimate the annual average rate at which water would need to flow to generate the power for that home (gallons per minute or cubic meters per second). Make your estimates using a hydro system that is 90% efficient and in which the lake level is 20 m above the generator. Hydro plants work by converting GPE stored in the water to KE as it falls and turns a turbine.
The average household uses 8,900 kWh of electricity each year or 32,040,000,000 J per year.
The desnity of water is 1000 km/m^3, and the lake is 20m above the generator. Hydro plants convert GPE stored in water to KE as it falls and turns a turbine.

Homework Equations





The Attempt at a Solution


I honestly have no idea where to start with this equation. My professor has never gone over anything remotely like this in class, so I honestly do not know where to start!

What is the Relevant Equation relating the change in potential energy PE to the mass of an object and how far it falls? You've covered that, I'd bet.

How much does a cubic meter of water weigh?

How much PE is lost if a cubic meter of water falls 20m?

Factor in the 90% efficiency...

How much energy per cubic meter of water falling can you convert into electricity?

And so on...
 

1. What is hydroelectric generation?

Hydroelectric generation is the process of converting the energy of flowing water into electricity. This is done by using dams or other structures to control the flow of water, which then turns turbines that generate electricity.

2. How does hydroelectric generation work?

Hydroelectric generation works by using the gravitational force of falling water to spin turbines. This motion is then converted into electricity through a generator. The water is typically stored in a reservoir and released through a channel, known as a penstock, to create the necessary force to turn the turbines.

3. What are the benefits of hydroelectric energy?

Some benefits of hydroelectric energy include its renewable nature, as water is constantly replenished by the water cycle. It also produces clean energy with no emissions or pollution. Additionally, hydroelectric dams can also provide flood control, irrigation, and recreational opportunities.

4. What are the challenges of hydroelectric energy?

One challenge of hydroelectric energy is the potential impact on the surrounding ecosystem. Dams can disrupt the natural flow of rivers and affect the habitats of aquatic animals. There are also concerns about the displacement of communities and the potential for dam failure. Maintenance and repair of aging infrastructure can also be costly.

5. How does hydroelectric energy compare to other renewable energy sources?

Hydroelectric energy is one of the most established and efficient forms of renewable energy, with a high energy output and low operating costs. However, it is limited by geography, as suitable locations for hydroelectric dams are not available everywhere. Other renewable energy sources, such as solar and wind, have a wider geographic range but may not have the same energy output as hydroelectric power plants.

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