How Hydropower Works
Hydroelectric dam on the river, water discharge from the reservoir, aerial photography
In the most common setup, dams slow down an existing river to redirect some of its kinetic energy. That controlled river flow rotates specifically designed turbine generators to produce electricity. This differs from fossil-fuel plants that must burn coal, gas or oil to release thermal energy for conversion into electricity through steam and turbines.
Since flowing water constantly renews itself via existing natural hydrologic cycles, hydropower can reliably generate emission-free renewable power indefinitely without being depleted. The only primary inputs involved are installation and maintenance of appropriate dams, reservoirs, water conduits, and power generators.
Cleaner Air
Compared to popular fossil fuel-based options, hydropower emits virtually no pollution or greenhouse gases like carbon dioxide during electricity generation. Coal and natural gas plants must continuously burn massive volumes of non-renewable carbons to release enough heat for steam turbines. This combustion directly pumps hundreds of millions of tons of CO2 along with soot and other dangerous byproducts into the atmosphere every year per plant simply as an intrinsic part of their essential operational processes. Facilities also commonly suffer external pollution incidents like huge coal ash spills.
In stark contrast, most hydropower facilities generate no direct emissions whatsoever during electricity production thanks to using established renewable water flows free of carbon impacts. The only exceptions come from small supplemental operations, like emergency generators or construction vehicle emissions during initial site developments. However, these onetime activities prove negligible compared to the constant burning and rampant external emissions problems from fossil fuels.
Ecological Improvements
While exact benefits depend on specific site conditions and turbine types installed, studies show hydropower electricity averages much lower lifetime greenhouse gas emissions than conventional options. The industry also continues improving environmental practices through more rigorous planning, assisted migrations before reservoir formations, mandated wildlife protections, fishery management, and advanced technology applications.
Mindful hydro resources utilize natural water flows for electrical generation without introducing problematic external byproducts or unsustainable resource depletion issues typical of most mainstream alternatives. Though no energy solution proves perfect, hydropower remains among the cleanest and greenest thanks largely to its established renewability and emission-free generation processes.
Potential Downsides
While hydropower clearly provides environmental advantages as a renewable emission-free electricity solution, critics rightfully note developing new facilities still incurs some negative consequences. Damming water flows inherently alters regional ecologies by converting flowing rivers into artificial stationary reservoirs. These new lake environments change natural habitats, water tables, soil characteristics, plant covers and animal behaviors through interrupting existing hydrologic, geologic and biologic conditions fundamental organisms depend upon for millennia.
Additionally, sites with large elevation drops for increased power potential often require extremely tall dams with substantial concrete demands during construction along with continuing operational needs like spillway maintenance. The high infrastructure requirements increase overall lifetime environmental footprints despite ongoing electricity generation proving mostly clean.
Conclusion
Hydropower qualifies as one of the greenest renewable energy solutions available thanks to its reliable water flow resources and emission-free generation portfolio. Though critics rightly note select negative effects from transitioning natural water flows into dammed reservoirs, strategic development greatly minimizes consequences while still expanding sustainable clean energy nationwide. With environmental protections and conscientious planning, increasing America’s hydropower capacity promises a much greener future for everyone.
