As solar panels continue to decrease in price while becoming more efficient, many people ask us to compare our favorite form of renewable energy with other power sources. Chariot Energy is happy to discuss these questions. We believe in educating people about the advantages that all green energy has over fossil fuels. And since hydropower has long been the mainstay form of sustainable energy in the global energy mix, we wanted to help people understand it.

In this article, we will discuss the following:

Definitions for solar and hydropower
The big differences between them
The pros and cons of using them as power sources

Both are viable and popular forms of energy generation, but we must understand how they work.

What is Solar Power?

Chariot Energy's Oberon solar farm located in West Texas

As you’d imagine, we’ve written a considerable amount on solar energy, light waves that we as humans use to complete a task, whether that’s cooking food, drying clothes, or boiling water. To that end, we’ve used the power of the sun for centuries.

But when we talk about creating electricity to power our homes and businesses, we’ve entered the new age of solar. Thanks to the introduction of photoelectric cells, we can now harness the sun’s rays to generate electricity that can then be transmitted to buildings. Today, solar companies like Chariot use solar panels (often arranged in massive arrays called solar farms) or concentrating solar power plants (CSP plants) to create electricity.

What is Hydropower?

Much like solar power, hydropower has been around for millennia. Flowing water turned large wheels, which spun other large equipment, including sawmills, granaries, and irrigation systems. It’s the reason so many civilizations throughout have always been situated near or around a river.

In terms of creating electricity from water, this is called “hydroelectricity.” In 1882, the world’s first hydroelectric power plant began operating in Wisconsin, as the Fox River began turning massive water turbines to create electricity. From there, humans have created massive dams situated on and around powerful bodies of water to create electricity to power homes and businesses.

What are the Primary Differences Between Solar Power and Hydropower?

The similarities between hydroelectricity and solar energy are rather fundamental. After the construction and installation of the necessary machinery, both use 100% renewable sources to create electricity with absolutely zero carbon emissions. Outside of very dramatic circumstances, the earth will never run out of the water and sunlight required for energy generation.

When it comes to their differences, three prominent ones stand out:

Location
How they work
How they affect the planet

The first two differences are quite stark, while the third is a bit more nuanced than you’d imagine.

Location

It’s rather obvious from their names that solar and hydropower must be created in dramatically opposite locales: one needs lots of water and the other needs lots of sunshine.

Hydroelectricity requires either a naturally strong rushing river or the man-made creation of those effects through the construction of a dam.
Solar energy needs access to lots of sunlight without any nature blocking the solar arrays, both in terms of foliage and inclement weather that could block out the sun.

To that end, you’ll rarely see a hydro plant or solar farm in the same relative area. Substantial rushing rivers usually bring with them trees, grasses, farms, and civilization. Wide expanses of flat land that don’t receive regular rainfall or cloud cover usually exist in areas without many people or greenery.

We’ll discuss the follow-up issues with these locations later.

How Electricity is Generated

This is the big one, as solar and hydro create electricity in wildly different ways.

With photovoltaic solar cells, the sunlight hits two alternately charged sheets of silicon to produce an electric current that then is sent down electrical wires.
Concentrating solar power plants point sunlight at water using highly reflective mirrors point, and the converted steam spins turbines to generate energy.
At a hydroelectric plant, flowing water spins a turbine to create electricity.

Yes, CSP plants and hydro plants both spin turbines, but the former is much less efficient than the latter. Directing the sunlight to boil water for a steam turbine is much more difficult than ensuring water can flow through a turbine.

Environmental Impact

In terms of how these renewable energy sources interact with their environment, it all comes down to what happens before and during construction.

Solar Power

Everything centers around extracting the necessary materials from the earth, specifically the mining operations and the people hired to locate those metals. To that end, the solar industry is working toward more sustainable ways to extract the materials needed to lessen the environmental impact.

Additionally, all solar energy is considered green, clean, and renewable, which can’t be said about some forms of hydropower.

Hydropower

Excavating the necessary area to create the dam can cause problems for the local ecosystems. Potential problems include:

Changing the course of a river
Disrupting plant life
Bothering local animal populations
Displacing people currently living in what would become the new floodplain

Because of the substantial environmental impact caused by creating large-scale plants, hydropower is typically regarded as renewable energy, but not green or clean.

Our Comparison of Solar Power and Hydropower

Ultimately, both renewable energy methods benefit the planet because they don’t create carbon emissions or any other environmental degradation. They are remarkably clean and efficient, often needing very little in the way of regular maintenance or repair.

Sure, we’re biased toward solar power, but we also believe that hydropower is a very successful way to create electricity that doesn’t burn fossil fuels or pollute our atmosphere with hydrocarbons.

Pros and Cons of Solar Power

Pros	Cons
Plenty of sunlight on the planet	Generation can be unpredictable
Zero carbon emissions	Higher upfront costs
Affordable	Environmental impact of installation
Can be installed on roofs	Doesn’t work at night
Long lifecycle	Poor transmissions options from large facilities

Pros and Cons of Hydropower

Pros	Cons
Plenty of water on the planet	Dependent on geography
Low carbon emissions	Expensive upfront costs
Lowest cost to generate	Environmental impact of installation
Predictable generation	Needs high water speeds to operate
Runs regardless of climate or time
Long lifecycle

Which is Better: Hydropower or Solar Power?

If we’re answering for the future of our planet and the long-term health of the environment, then the answer is both.

We need both of them working in conjunction with other forms of clean energy if we’re going to break our reliance on fossil fuels. Truly, we shouldn’t have to choose one or the other when we should look for every opportunity to diversify the amounts and types of renewable energy we use to power our homes and businesses.

The more ways you can take advantage of renewable energy, the better. This includes installing rooftop solar; choosing an energy plan backed by solar, wind, or hydro; and/or advocating for the adoption of sustainable energy sources in your city, region, and state.

Sources:

Solar Energy vs. Hydropower: What’s the Difference?