Have you ever stood by a rushing river and felt its incredible force?  That power doesn’t just go to waste! 

Hydropower uses the energy of moving water to create electricity. It’s been around for a long time and is one of the most important sources of clean energy we have.

Reports also shows that hydropower is a global leader in renewable energy generation, currently supplying over 18% of the world’s electricity – that’s more than all other renewable sources combined!

In this blog post, we’ll go through what hydropower is, how much it costs to use hydropower and the different ways we can capture this powerful resource.  

So what is hydropower?

What is Hydropower?

Hydropower, also known as hydroelectric power, is a form of renewable energy that harnesses the energy of flowing or falling water to generate electricity. 

This method of power generation has been used for centuries, initially for mechanical tasks like grinding grain and sawing wood, and now predominantly for electricity production.

The concept behind hydropower is straightforward: the kinetic energy of moving water is captured and converted into electrical energy. 

This is typically done by using a dam to create a reservoir, controlling the flow of water, and directing it through turbines. As the water flows through the turbines, it spins them, which in turn activates generators to produce electricity.

The History Of Hydropower

Hydropower has a long history that goes back thousands of years. To grind wheat into flour, for instance, the Greeks used water wheels almost 2,000 years ago. 

Bernard Forest de Bélidor, a French hydraulic and military engineer, published Architecture Hydraulique in the middle of the 1700s, which marked the beginning of the development of the modern hydropower turbine. 

The early half of the 1800s saw a number of significant advances in hydropower technology, and the last century has seen a number of hydroelectric improvements that have contributed to hydropower’s rise to prominence in the US mix of renewable energy sources.

How Does Hydropower Work?

Hydropower works by capturing the energy from moving water and converting it into electricity. Here’s a step-by-step look at how this process typically unfolds:

• Water Collection

A dam is built across a river to create a reservoir or to heighten an existing body of water. The reservoir stores a large amount of potential energy in the form of water at a higher elevation.

• Controlled Release

Water from the reservoir is released in a controlled manner through gates or penstocks (large pipes). The amount of water released can be adjusted to control the power output.

• Energy Conversion

As water flows down through the penstocks, its potential energy is converted into kinetic energy. This fast-moving water is directed at the blades of a turbine.

• Turbine Movement

The force of the moving water spins the turbine. The turbine is connected to a generator, and as it spins, it turns the generator’s rotor.

• Electricity Generation

The spinning rotor inside the generator creates a magnetic field, which induces the flow of electrons in the generator’s coils, producing electricity.

• Power Transmission

The generated electricity is then transmitted via power lines to homes, businesses, and industries, where it is used to power electrical devices and systems.

Types of Hydropower Systems

Hydropower systems can be classified based on their size, design, and the method by which they harness water’s energy. Here are the main types:

Impoundment Hydropower

• Description: This is the most common type of hydropower system, which involves the construction of a dam across a river. The dam creates a large reservoir where water is stored.

• How it Works: Water from the reservoir is released through turbines located at the dam’s base, generating electricity. The flow of water can be controlled to meet electricity demand.

• Examples: The Hoover Dam in the United States and the Three Gorges Dam in China.

Run-of-the-River Hydropower

• Description: This type of system does not require a large reservoir. Instead, it utilizes the natural flow of rivers.

• How it Works: Water is diverted from the river into a canal or penstock, where it flows through turbines and generates electricity before being returned to the river.

• Examples: Several small-scale plants and some larger installations like the Chief Joseph Dam in the USA.

Pumped Storage Hydropower

• Description: This system is used for energy storage and managing electricity supply.

• How it Works: During periods of low electricity demand, excess electricity is used to pump water from a lower reservoir to an upper reservoir. During peak demand, the stored water is released back down to the lower reservoir, passing through turbines to generate electricity.

• Examples: The Bath County Pumped Storage Station in Virginia, USA.

Micro and Pico Hydropower

• Description: These are small-scale hydropower systems designed for local or individual use. Micro-hydropower systems typically generate up to 100 kilowatts, while pico-hydropower systems generate less than 5 kilowatts.

• How it Works: These systems often use small streams or rivers without requiring significant infrastructure, making them ideal for remote areas.

• Examples: Off-grid installations in rural or isolated communities.

In-stream Hydropower

• Description: Also known as hydrokinetic or free-flow hydropower, these systems generate electricity without altering the flow of the river.

• How it Works: Turbines are placed directly in the river or tidal currents. The natural movement of water spins the turbines, generating electricity.

• Examples: Projects like Verdant Power’s Roosevelt Island Tidal Energy (RITE) project in New York.

What is the cost of Hydropower?

The cost of hydropower varies based on the size and type of the project, location, and environmental considerations. Here’s a simplified breakdown; 

Initial Capital Costs

• Construction Costs: Building dams, powerhouses, turbines, and other infrastructure. Large projects can cost billions, while smaller ones are much cheaper.
• Land and Relocation Costs: Acquiring land and relocating communities if needed.
• Engineering and Design Costs: Planning, design, and feasibility studies.
• Example: Small systems can cost $1,000 to $20,000 per kilowatt installed.

Operational and Maintenance Costs

• Routine Maintenance: Regular upkeep of equipment.
• Operational Staff: Hiring personnel to run the facility.
• Repairs and Upgrades: Periodic updates to maintain efficiency.
• Example: Generally low, around $5 to $20 per megawatt-hour (MWh).

Environmental and Mitigation Costs

• Impact Assessments: Evaluating and mitigating environmental impacts.
• Wildlife Protection: Measures to protect local ecosystems.
• Example: Costs vary widely based on project specifics.

Financing Costs

• Interest on Loans: Costs associated with borrowing money.
• Return on Investment: Expected returns for investors.

Decommissioning Costs

• End-of-life Management: Dismantling structures and site restoration.

What are the Pros & Cons of Hydropower?

So now let’s take a good look at some of the pros and cons of hydropower; 

Is hydropower renewable?

Hydropower is indeed considered a renewable energy source. It relies on the natural flow of water, which is continuously replenished through the water cycle, making it a sustainable and reliable source of energy. 

Unlike finite resources such as fossil fuels, which are non-renewable and can be depleted over time, the water used in hydropower projects remains in constant circulation, ensuring a perpetual source of energy. 

This renewable nature of hydropower makes it an attractive option for reducing reliance on fossil fuels and mitigating climate change.

However, it’s important to note that while hydropower itself is renewable, the environmental impacts associated with its development and operation must be carefully managed. 

Also Read: A Beginner’s Guide to Solar Energy

Final Thoughts

So far we’ve learned hydropower is a learned it’s a clean energy source that uses moving water to make electricity. 

It helps reduce pollution and keeps our planet healthy.  Even though there can be challenges, hydropower keeps getting better at providing lots of power for many people.

Hydropower shows how clever we can be when it comes to using nature’s energy for good. It helps light our homes, run factories, and even power whole cities, all while building a cleaner future for us all.