Hydropower isn’t new by any means; humans have been harnessing the power of water for thousands of years (though back then, the energy was mostly used for tasks such as grinding wheat into flour). It wasn’t until 1880 that hydropower was first used in the U.S. industrially. And two years later, in September of 1882, a Wisconsin plant on the Fox River became the first to sell the electricity it produced.
Today, there are around 15,000 operational hydropower plants in the US — almost every state has at least one. As the most widely used form of green energy management in the world, hydropower accounts for 17% of the total electricity produced. Yet, considering water is our largest contributing renewable energy source (and one of the oldest power sources known to humankind), we don't tend to know much about it.
How Hydroelectric Power Works
Hydropower plants come in three different varieties: diversion, pumped storage, and impoundment. However, the most common form of hydroelectric green energy management, the one most of us picture when we think of hydroelectricity, is impoundment; a facility using a dam to store large quantities of water in a reservoir. In these plants, the water flows through the dam’s gates and enters the penstock, a pipe or channel leading to the turbine, where it is pulled downwards by gravity. At the end of the penstock, the moving water pushes the blades of the turbine, causing it to rotate. Connected to the turbine is the generator, which spins with the turbine, creating electricity.
Diversion, which is often referred to as run of the river, doesn’t always necessitate a dam; instead, these facilities redirect part of a river, stream, or creek through a channel or penstock to the turbine. This form of hydroelectric green energy management, like the others, requires that the water source have a large change in elevation in order to get the momentum needed to generate electricity.
The last form, pumped storage, is one of the few methods we have to store energy; as such, it accounts for a whopping 95% of US utility-scale energy storage. These facilities have a lower and an upper reservoir; the water moves from the upper reservoir to the lower to generate electricity during high demand periods (similar to impoundment), and from the lower to the upper to store it when demand is low.
How Much Energy Can Hydropower Create?
From a physics perspective, hydropower plants facilitate the conversion of kinetic energy (falling water) to mechanical energy (spinning turbine) to electric energy (the generator). Two primary factors determine the amount of power hydropower facilities can produce; the head and the flow. The head is the distance the water falls — the change in elevation between where the water starts and ends its journey. In an impoundment plant, typically, the higher the dam the larger the head. The other factor to consider is the flow, the amount of water moving through the system, which is typically controlled by the dam. Flow and head are both directly proportional to the power created, so a big part of green energy management is finding and building large enough amounts of each.
More specifically, The Bureau of Reclamation found that you can determine the approximate amount of mechanical energy (theoretical horsepower, or THP) generated by an impoundment facility with the following equation:
THP = (Q x H) / 8.8
THP = theoretical horsepower
Q = flow rate in cubic feet per second
H = head in feet
8.8 = a constant
To find how much electrical power the facility can produce, we can convert the mechanical measurement into electrical units:
Watts = THP / 746
Benefits Of Hydroelectric Green Energy Management
Hydropower is an incredible resource; it’s fueled by the water cycle, so it replenishes itself. Plus, since nothing needs to be burned to harness its power, hydroelectricity is a clean energy source as well as a renewable one — and that’s just the tip of the iceberg when it comes to the benefits of hydropower.
Impoundment Plants Create Reservoirs
One of the main benefits to the community surrounding a hydroelectric plant is the reservoirs they create. Reservoirs collect and store a vital resource, water, which those nearby can use for drinking and irrigation. What’s more, reservoirs allow for a plethora of water-based recreational activities, such as swimming, boating, and fishing.
Hydropower Provides Backup For Other Forms Of Green Energy
Most forms of energy can’t be stored, which occasionally poses a problem for the grid; when demand outweighs supply, there’s often no backup option — no emergency stores. Pumped storage hydropower is a rare exception. This type of green energy management plant can react instantly to changes in demand, supplying more energy when needed and less when it’s not. The advantages of this are immense, especially when it comes to expanding renewable energy. Wind and solar power are intermittent energy sources, meaning that they fluctuate in their ability to provide power. By tying these sources to hydroelectric systems, there won’t be any shortages during windless or cloudy days - the water power can supplement when needed.
Simplify Your Green Energy Management With GIS
Hydropower is undoubtedly one of the best electricity sources available to us, but not every river or stream is well suited for it. Luckily, with GIS technology, sourcing locations is made far easier.
Hydropower, at its core, runs on the water cycle; there needs to be enough water available in order for it to generate electricity. Accordingly, the best areas for a hydroelectric plant will need regular rainfall (which is partially why around half of US utility-scale hydroelectricity is generated in Washington, Oregon, and California). With GIS mapping tools, professionals can visualize precipitation data, allowing them to source locations with enough annual rain to make the plant economically feasible.
As the head is directly proportional to the amount of power a hydroelectric plant can generate, the best areas for new plants will also need rivers or streams with a large elevation change. Without software, this would be difficult to determine, but with Land id™ (formerly MapRight), clients can add layers for topography and water sources to easily identify suitable areas and assess their potential to generate power.
Any new construction will have a few additional land requirements; the area has to be accessible. GIS will allow professionals to map access roads and highways to ensure builders can get to the land, topography to make sure the slope is safe for building, and soil strength to prevent any fallout from heavy machinery. However, just because the land is accessible doesn’t mean it’s available. On Land id™, professionals can also add a layer for land use to check if the area is zoned for this type of green energy management project.
And of course, any power plant needs a way to distribute the energy produced. By adding layers for transmission lines and substations, green energy professionals can easily assess whether an area has the resources necessary to take on a new plant.
Get Started With Land id™
Water could very well be the future of energy; it’s packed with underutilized potential. With our advanced GIS technology, Land id™ has everything green energy management professionals need to begin taking advantage of this incredible resource. Ready to get started? Sign up for a 7-day free trial of Land id™ today!