Hydropower is the largest source of renewable energy. It supplies 16% of the world’s electricity and has made a tremendous impact on our fight against climate change. In the last 50 years alone, it has prevented 100 billion tons of greenhouse gases—enough to offset the carbon footprint of the USA for the last 20 years.
Hydropower is a powerful technology that can help save the planet. What’s amazing is that this tool has been around for much longer than most people think. In this article, we’ll look at the history of hydropower and how it has evolved through the centuries.
Hydropower in Ancient Civilizations
The water wheel is the first device that ran on hydropower. Historians believe that it was invented by a Roman engineer called Vitrivius in 4000 BCE. His design involved a vertical wheel that was fixed to an axle. The water flow would push the wheel, causing the axle, gears, and any other object connected it to turn.
The idea spread across the rest of Europe, and then to the Arabian peninsula and Asia. It is important to note that China also invented its own version of the water wheel in 1 CE, even before the Roman invention reached its shores. Zigong, a disciple of Confucious, made a horizontal water wheel with a similar gear-and-axle mechanism.
The evolution of the water wheel design
The waterwheel was the first mechanical device that could automate repetitive or labor-intensive tasks. As people used it for different purposes, they refined the design to suit their needs or solve certain problems that would occur during operation.
For example, water wheels were originally placed in rivers that was strong enough to turn the blades. However, people faced the problem of controlling the water levels, which could change during the seasons. If it was too low, the wheel would slow down; if it was too high, the wheel would become submerged and stop completely.
This was solved by controlling the water source. Instead of installing the wheel directly on the river, they diverted water flow into an aqueduct. This enabled them to fully control the water flow, direction and volume.
Uses and applications
Water wheels were initially used in agriculture to irrigate fields or grind grain into flour. Eventually, large water wheels were used for many other purposes, such as mining (crushing rocks and ores, removing water from mines) and navigation and transportation (geared wheels were used to work odometers and propulsion devices).
Water wheels and aqueducts were also used to channel drinking water to villagers. The ability to control and maintain water supply was one of the factors why populations could grow into towns, and expand the cities.
Hydropower in the Medieval Age
Hydropower became even more widespread during the Middle Ages (500 to 1500 CE). There are many archaeological findings of water mills in Europe, Arabian Peninsula, Africa, and Asia. And an entry from the Domesday Book—which meticulously documented the properties of England in the 1080s—recorded that there were 5,600 water mills in 3,000 towns.
By that time, people were already connecting water mills to hammers, pumps, and other tools to speed up production. They could now make flour, paper, glass, fabric and other key items at larger commercial volumes.
This coincided with the increase in trade between regions, with better roads and more powerful ships that could transport bulk goods. Hydropower—and the ability to increase and automate production—was driving the economy, and laying the foundation for the Industrial Revolution.
Hydropower during the Industrial Revolution
During the Industrial Revolution, many engineers worked to improve water wheel technology so it could be stronger, faster, more reliable, and water efficient.
For example, French engineer Alphonse Sagebian improved the breastshot water wheel so it could reach 90% efficiency even at low water levels. It also was less noisy, and operated well even when there were drainage problems. His invention eventually became known as the Sagebian Wheel.
French mathematician Jean-Victor Poncelet replaced the flat blades of traditional water wheels with curved or cylindrical blades. This helped reduce the turbulence and loss of energy, and increased energy efficiency to 84%. This became one of the most common commercial windmill models in France and Germany, and even won the prestigious Prix de Mecanique from the French Academy of Sciences.
Other inventors found ways to use hydropower to directly power appliances. Richard Arkwright’s Water Frame used hydropower to automate a spinning machine for making cotton thread. It could spin 96 threads simultaneously, and the cotton was stronger and harder. He then set up the Cromford Mill in 1771, which was the world’s first factory system.
Water Turbine: The Turning Point for Hydropower
For centuries, water was used to automate machines. However, the biggest breakthrough in the history of hydropower was when it was successfully used to create electricity.
In 1827, drawing from research by Sagebian and Poncelet, a French engineer named Benoit Fourneyron successfully developed a turbine that could produce 4.5 kilowatts. It had two sets of blades that curved in opposite directions, which helped maximize the power from water flow. By 1837, he was able to improve the turbine to produce 45 kilowatts.
In the 1850s, British-American civil engineer James Bicheno Francis developed a “mixed flow” turbine. Unlike Fourneyron’s design, it would not stop turning if it was exposed to backwater, and reached a then-unprecedented 88% efficienc rate. This design is still the most widely used turbine today, and is the standard for many hydro-electric facilities.
In the 1870s, Lester Allan Pelton developed an impulse water turbine, which converts kinetic energy from the pressure of the water. The design is also being used today, especially in areas where water sources have a high hydraulic head at low flow. Meanwhile, the Francis turbine is used where water sources have low to medium hydraulic heads.
The First Hydropower Projects
In 1878, William Armstrong used water from a nearby lake to turn on a lamp in his home at Northumberland, England. Though many people had performed experiments on it, this was the first time in the history of hydropower electricity that anyone used it for a practical purpose.
From there on, hydro electricity projects became even bigger.
In 1880, the Wolverine Chair Factory in Grand Rapids, Michigan used it to power its lamps—the first instance of commercial or industrial use. Other companies soon followed suit.
In 1882, the world’s first hydropower plant opened in Appleton, Wisconsin. In the next four years, 44 more power stations were built in the United States and Canada. A few years later, Germany also introduced the first three-phrase hydro-electric system—the first of many innovations that would help make plants bigger and more cost-effective.
The Hydropower Boom
By the 1890s, there were hundreds of hydropower plants all over the world. However, the largest and most famous project was the Edward Dean Adams Power Plant at Niagara Falls. While it was not the first plant that was built in the area, it got global attention because of its sheer size and the collaboration of General Electric and Westinghouse, two of the biggest names in electricity at the time.
By the 1920s, hydropower plants were already responsible for 25% of the United States’ total electricity generation. By the 1940s, thanks to massive hydropower projects such as the Hoover and Grand Coulee dams, this number rose to 40%.
The trend continued up to the 1980s. As energy demands increased because of economic and population growth after the war, governments around the world funded the construction of hydropower plants as well as research and development.
In 1984, Brazil opened the Itaipu Dam which had a starting capacity of 12,600 MW. The facilities were later expanded, and increased energy production to 14,000 MW. It was the world’s largest hydropower facility until 2008, when China’s Three Gorges Gam took the title with a 22,500 MW capacity.
Construction of hydropower plants tapered off by the 1990s, because of economic recessions and lack of funding. However, growth regained momentum in Asia and South America, which increased its hydropower capacity by 65% from 2000 to 2017.
This “Hydropower Revival” was mainly driven by multi-lateral agreements, lending from the World Bank, and a change in government policies because of the Paris Agreement’s sustainability goals.
Five Biggest Hydropower Dams in the World
- Three Gorges, China. This ambitious hydropower project took 19 years to complete, with construction beginning in 1993 and completed in 2012. It generates 85THw per year, enough to provide power to two major cities (including Shanghai) and nine provinces.
- Itaipu, Brazil and Paraguay. This plant straddles the Parana River, which lies between the borders of the two countries. It produces about 103.1 million MWh a year, enough for 90% of Paraguay’s electricity and 15% of Brazil’s. The energy it produces has helped prevent 67.5 million tons of carbon dioxide emissions.
- Guri, Venezuela. Located at the located Caroni River, which is found in the southeastern region, this plant generates 12,900 GWh of energy or 70% of the country’s total electricity needs.
- Tucurui, Brazil. This plant generates 8370 MW a year. Tucurui and Itaipu’s combined hydropower production provides 80% of the country’s energy needs.
- Grand Coulee, USA. Found on the Columbia River in the Washington state, this plant has 6809 MW annual capacity. It accounts for over a third of the renewable energy production of the US, and 6.1% of the total electricity production.
The future of Hydropower
Today, hydropower produces a fifth of the world’s electricity, and this is expected to increase as renewable energy becomes more important for sustainability goals. While solar and wind energy are increasing, these are still more expensive per kilowatt hour.
However, for hydropower to be embraced as the main source of energy, it has to be more efficient and environmentally friendly. Here are some of the new technologies that are emerging in the history of hydropower.
Damless Hydropower Plants
To create large reservoirs, water sources have to be controlled. This has affected the surrounding animal, marine and plant life. For example, the large dams in the US have blocked more than half of the spawning and breeding grounds of salmon and other fish.
“Damless hydropower plants” generate energy using the natural flow of water. These can be installed in rivers and will not displace or damage the animals and plants in its surrounding eco system. However, scientists are working on improving the energy production, which is significantly lower than traditional hydropower plants.
Damless plants can also help troubleshoot problems of lower water reservoir levels, which may occur more often because of climate change. The technology can help increase electricity production by making use of smaller bodies of water, rather than relying on one big dam for a city’s energy needs.
Marine and hydrokinetic (MHK) technology harvests electricity from ocean water. While still in its infancy, if this is successfully developed, it turns the ocean into one big power bank. However, scientists are working on how to make the design safe for marine creatures, and improving the structures’ stability and safety in rough ocean currents.
There are two kinds of MHKs: some float near the surface like buoys, while others are located underwater and have spinning turbines. Both convert the energy from the movement of the waterand then convert it into electricity. The devices are then connected to the electrical grid through cables.
Traditional hydropower plants are quite large, and often require several years (and millions of dollars) to construct. An emerging technology, modular hydropower, makes it possible to “start small.”
The modular systems are spread out over an area, such as sections in a river or in city waterways. Aside from being more affordable, it is a more convenient option for landlocked cities, or for remote communities.
However, the challenges of modular hydropower is that it cannot come close to the amount of electricity generated by traditional plants. And having to install and run several small units may actually drive up the cost per kilowatt hour, and lead to longer long-term costs.
These technologies—and other improvements and inventions—will mark the next chapter in the history of hydropower.