Hydroelectricity began with one lamp in a Victorian art gallery
In 1878 the industrialist William Armstrong rigged a water-driven generator at Cragside, his Northumberland house, to light a single arc lamp in his picture gallery. It was the first hydroelectric scheme anywhere. Within about a century, dams in South America and China would generate power measured not in lamps but in tens of gigawatts.
Water had turned machinery long before it made electricity. Hydraulic power drove the early Industrial Revolution, and Richard Arkwright's water frame of 1771 helped birth the factory system. Once the electrical generator arrived, pairing it with a waterwheel was obvious. In September 1882 generators at St. Anthony Falls lit arc lamps on a Minneapolis street, and that same month Edison's Vulcan Street Plant in Appleton, Wisconsin began producing about 12.5 kilowatts. By 1889 the United States alone had 200 such stations.
People nicknamed it white coal. Hoover Dam's 1,345 megawatt station was the world's biggest in 1936, overtaken by Grand Coulee in 1942. Itaipu in South America took the crown in 1984 at 14 gigawatts, and Three Gorges in China passed it in 2008 with 22.5. Only seven plants worldwide exceed 10 gigawatts, yet some produce more than twice the capacity of today's largest nuclear stations. Norway, Paraguay, Brazil and the Democratic Republic of the Congo get over 85 percent of their electricity this way.
Most stations let dammed water fall through a large pipe called a penstock onto a turbine; the output depends on the volume and the height of the drop, known as the head. Because gates can open or close within seconds or minutes, dams can chase demand. Pumped storage goes further, pushing water uphill when power is cheap and releasing it at peaks. In 2021 it provided almost 85 percent of the world's 190 gigawatts of grid storage. Run-of-the-river plants skip big reservoirs and use whatever flow arrives.
In 2023 hydropower supplied about 15 percent of world electricity, more than all other renewables combined and more than nuclear. The costs are real: drowned farmland, displaced communities and disrupted river life, and flooded rainforest can release substantial greenhouse gases. Small micro hydro setups of up to 100 kilowatts pair neatly with solar panels, since streams often run strongest in winter when sunshine is weakest.
Source: Hydroelectricity
