Imagine getting electricity from the creek running through your property. Hydropower is one of the most popular forms of renewable energy today. A micro-hydro system is easy to install and can be a stand-alone system or work with other forms of power.
According to The National Hydropower Association, hydro-power accounts for “52% of America’s renewable electricity generation and 7% of total electricity generation.” In fact, hydropower placed in large rivers at dams power complete towns. The Grand Coulee Dam located in Washington State on the Columbia River generates 6908 MW of electricity.
The process of hydraulic energy generation works like so - flowing water places pressure on a turbine causing it to spin. This spinning turbine then causes a generator to produce energy, which is then transformed into usable electricity.
In this article, I will discuss how hydropower works, the distinct parts of it, the pros and cons of the system, and how to create and implement your own micro hydropower system.
The Grand Coulee dam produces electricity for neighboring towns but has been much criticized by environmental and Native American groups for destroying fish habitats. Photo by Gregg M Erickson
Hydro History
Harnessing energy by using water was performed by humans over 2,000 years ago. Water-powered wheels were used by the Greeks, Romans, and Chinese to grind wheat.
The technology of the hydro turbine developed throughout the 18th century, and the Francis Turbine developed by James Francis in 1849 became the blueprint for the turbines we use today.
Additionally, the first use of hydropower to generate electricity in the U.S was in a chair factory in Michigan. The goal was to power 16 arc lamps.
Two notable developments being the building of the Hoover Dam in the 1930s and the New Deal construction programs in the 1940s, making hydropower become 40% of electrical generation in the U.S.
Hydraulic technologies advanced significantly over time and the use of this kind of power became widespread throughout the U.S as well. As of 2019, Washington, California, and Oregon made up half of the conventional hydropower generated in the United States. New York and Alabama also seem to generate hydroelectricity considerably more than other states.
When we think of hydropower we often think of the old grist mills such as the Glade Creek Gristmill in West Virginia. These were important in early American communities to grind grains into flour.
How Hydropower Works
Hydropower simply works by the movement of water. In its simplest form, like in a grist mill, the water flows over the wheel causing it to turn. That movement then caused flat stones to move against each other which ground the grains.
Today’s turbines are much more efficient. Kinetic energy, which comes from flowing bodies of water such as streams or rivers, and is transformed into mechanical energy by the spinning of the turbine. The generator converts the mechanical energy into electricity, which we are then able to use.
The Water Cycle
Another important aspect to understand about hydropower is how it would be incomplete without the water cycle. Needless to say, hydro works best where there is adequate rainfall to keep streams and rivers flowing consistently.
To refresh your memory (if needed), the four steps of the water cycle are evaporation, condensation, precipitation, and runoff.
Solar energy heats the surface of bodies of water, causing the water to evaporate. Then the water vapor condenses in the form of clouds and precipitates back onto the ground in the form of rain, sleet, snow, or hail. The water then collects in rivers or streams through runoff, and the amount collected is what determines how much water is available for hydropower.
This video shows them testing a location fro hydro using a relatively small creek.
DIY Hydropower
Small hydropower systems that can be made and used by residents are called micro-hydropower systems. The systems are used by business owners, farmers, and ranchers and can generate up to 100 kilowatts of electricity. However, a 10-kilowatt system could provide enough power for a large home.
For those who have flowing water near or on their property, this form of energy generation may be suitable for you.
Components For Micro-Hydro
Pipeline, channel, or penstock for delivering water from the creek to the turbine
Turbine, pump, or waterwheel to transform flowing water into energy
Generator - transforms energy into electricity
Regulator - to control the generator
Wiring - to deliver the electricity
Batteries are optional depending on the system and should be located near the turbine
Basic set up for a micro-hydro system. Picture from energy.gov
Just Like With Real Estate - Location
Location definitely plays a role when it comes to considering whether hydropower would be the best option for you. You obviously need a flow of water. It is recommended that measure your water flow rates at different seasons to see if you would be able to run a turbine.
Energy.gove has a great webpage on Planning a Microhydropower Station.
You can place your hydro system right in the water. This is sometimes referred to as a Jack Rabbit turbine. These are smaller systems which only produce about 100 Watts per hour.
Other systems take water from the creek and pipe it to the location of the turbine.
This system would work by diverting water to the generator.
Stand-alone systems use batteries to store electricity, so keeping that in mind is important if that’s the option you want to choose. However, batteries may not be practical because resources for these systems are seasonal and the location of the batteries needs to be considered as well (need to be in close proximity to the turbine for better voltage transmission).
An interesting article details the work that Bill Isley and his wife experienced in order to build their homemade hydroelectric power plant.
I wanted to note a word of caution Isley included using hydropower. He stated that low voltage DC power is safe to handle but AC connections should only be handled by those experienced with those systems. He also described some issues he experienced due to the wire between the house and his inverter not being heavy enough, so that is something to keep in mind.
There are many things to take into account if you want to create your own micro hydropower system.
Two of the most important being the flow of water and vertical distance available (head), which allows you to determine how much power you will be able to obtain from your system.
Other factors to keep in mind would be cost or water rights. Making sure you know how much energy you need and having accurate measurements will allow you to figure out which kind of system is best for you based on your conditions (whether it be environmentally, economically, etc.) and how to go about building it.
It’s also important to be in touch with local authorities and understand the permitting process before investing in any creation so you know what you would/would not be able to do.
Part of the Mother Earth News Wiser Living Series
Different kinds of hydropower facilities
There are three types of hydropower facilities: impoundment, diversion, and pumped storage. These are used for large hydropower plants that produce electricity for communities.
The diversion (also called run-of-river) facility channels flowing water from a river or stream through a canal or penstock to spin a turbine. This is the most common system used by DIYers and those using micro-hydro. The water flow can be regulated by the facility but this system provides a continuous amount of electricity.
The most common type of facility is the impoundment facility. They are typically large and contain dams that store water in a reservoir. When the water in the reservoir is released it spins a turbine which creates energy which is then converted to electricity through the generator. These are the large dams that we see on rivers such as the Grand Coulee Dam pictured above.
The pumped storage facility harnesses water that is passed between upper and lower reservoirs. When there is low demand for electricity, water is pumped from a lower facility to a higher one and the energy is conserved. When there is a high demand for electricity, the water is released to the low reservoir and causes the turbines to spin, starting the process of electricity generation.
Offshore hydropower is an increasingly popular form of power generation that occurs through tidal currents or by the power of waves.
Parts of a Large Hydropower Plant
Large hydro facilities are built by damming rivers to create a large lake or reservoir of water. They have many different parts and produce large amounts of electricity.
Dam - many hydropower plants have dams that create reservoirs that hold back the water.
Intake - When gates on the dam open, water flows through the penstock which is a pipeline that leads to the turbine.
Turbine - the water causes the large blades of the turbine to spin.
Generator - the turbine is attached to the generator above it. As the turbine spins, so do magnets in the generator. These magnets rotate past copper coils, creating alternating currents by moving electrons.
Transformer - converts AC and converts it to higher-voltage currents
Outflow - Used water will travel through the pipelines and out into the river
Generators and turbines are typically sold as a package, so if you are purchasing them separately it’s important to match a generator with a turbine that has a similar speed or horsepower.
Inverters are also used by these systems in order to convert low voltage currents (direct currents) to higher power currents (alternating currents).
The components needed to build the system will vary depending on whether it's connected to a grid or a stand-alone system.
Take Away
Using hydropower overall seems to be a very beneficial and sustainable method of energy generation.
If you are willing and have the means to, you should definitely look into it. You could harness your own power and cut costs all while being environmentally friendly. Sounds good to me!
Guest Author, Jasmine Corbo, is a high schooler who loves the environment.
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