Hydropower explained

What is hydropower and how does it work?

Hydropower has been a viable alternative energy source for many years. As far back as the Roman Empire, water has been used to provide power for a variety of purposes. Simply stated, hydropower is the use of the force of water to produce energy.

Picture a waterwheel, often found on the rivers that pass by many historic industrial mills. The ability of one or more waterwheels to provide inexpensive power is the reason so many mills, starting with the historic Slater Mill (Pawtucket, RI) and throughout the 17th, 18th, and 19th centuries, were built on the banks of fast moving rivers.

The stronger the current, the more water power available to keep the wheels moving. The faster and more consistent movement of the waterwheels, the greater the power generated.

There are also specially constructed dams that produce hydroelectricity. Using water power, they convert this energy to electricity. A variation of the classic waterwheel can also churn out hydroelectricity, on a smaller scale.

Is hydropower a feasible alternative energy source?

Hydropower is – and has been a viable alternative energy source for many years. Currently, hydropower supplies almost 20% of the electricity around the world. However, there are some natural limitations that, both historically and currently, prevent hydropower from being used in all locations to energize large populations.

Although three-quarters of our planet is water, there are areas that have little access to powerful or large bodies of water to use for alternative energy. Should hydropower have to energize populations far away from the power source, distance issues must be solved. There is always the issue of sufficient strength and size of the hydropower source, which nature really controls.

A weak flowing river or small static body of water may not generate sufficient natural strength to drive a hydropower engine to provide energy to anything more than smaller projects.

Can hydropower replace fossil fuels?

The issue of expanding hydropower to the point that it replaces much of the fossil fuel usage in the world has been debated for years. The ability of hydropower to produce useful energy was proven hundreds of years ago. The efficiency of using water to create power and electricity is indisputable.

Obviously a renewable energy source, hydropower is also clean and mostly environmentally friendly. There are some vocal environmental detractors, however.

Because of natural, topographical, and, in some cases, political factors, over half of all hydropower in the U.S. is generated in only three states (Washington, Oregon, and California).

Washington, with the help of its mammoth state-of-the-art Grand Coolie Dam, produces almost 27% of U.S. hydroelectric power by itself. Montana also contributes with waterpower energy output. The rest of the U.S., however, is severely lacking in major hydropower contributions to date.

The positives of using this renewable energy source are impressive. The source, water, is free, renewable, clean, and has little waste product. Yet, some environmentalists have voiced concerns. Using dams or other in-water objects to harness hydropower can pose challenges to the natural eco-system of the source. Unhappy environmentalists often use the case of Pacific Salmon to emphasize their point.

Most are aware that the Salmon must make the long arduous journey up the Columbia River to reproduce. However, their progress has been stymied by the series of dams producing hydropower that block their mission.

They have been helped by the construction of so-called "fish ladders", which help the swimmers climb over the dams. Yet, what about the lesser publicized natural habitat changes that occur in every body of water containing dams or waterwheels?

Waterwheels and dams aren't the only methods of creating hydropower. Tidal, vortex, wave, marine current, and ocean thermal energy designs have already proven to generate power on a real world scale.

However, to date, these alternative creators of hydro energy have yet to develop into serious replacements for fossil fuels (oil, natural gas, and coal). The future may see this condition change as newer, more cost effective methods of delivering this energy to large areas may surface.

The hydropower industry still needs some improvements in its delivery systems. For example, think of a house heated by a forced hot water system. It requires a strong pump and efficient piping system to get the hot water, produced by the oil, gas, or coal burner, to all areas of the home quickly, while the water is still hot.

Expand this scale in your mind to conceive heating 1,000, 10,000, or 100,000 homes. While it can be done, it has yet to be done. The future will answer the fossil fuel replacement question.