Renewable energy

Sun, wind, and water

Solar energy, wind energy, and hydropower have been used in one form or another since the beginning of recorded history.  England’s Domes Day book dates from the 11th Century and recorded the number of mills powered by water in towns across the country. But you can go back to the Romans and before that to the Egyptians and the Chinese to find examples of ways in which the power of water and the wind was used to drive simple machines.

The wind and flowing water at first powered mechanical machines made from mainly from wood. But with the invention of electricity and its rapid evolution into a source of power for industrial machinery in the 19th Century, it wasn’t long before the flow of water was channeled and harnessed to generate electricity.

The first recorded hydroelectric machine was built  was in England in 1878—when a small turbine and generator produced electricity to light a single electric bulb.

But the idea rapidly caught on.

Just three years later there were hydroelectric plants installed in Grand Rapids, New York and Niagara Falls in the US, and in Ottawa, Canada. Then in 1895, the world’s largest hydroelectric plant at that time: the Edward Dean Adams power plant, started operating at Niagara Falls [1].

At about the same time, the first electricity-generating wind turbine was erected in Scotland by James Blyth and used to light his home. A few years later in 1887, a large wind turbine was built in Cleveland, Ohio, by Charles Brush.  It drove a 12 kW generator.

Electricity generated from solar energy and wind power didn’t really take off until the 20th Century. In rural America and Canada in the 1930s, kilowatt-scale wind electric turbines were commonplace—until electrification programs brought centrally-generated electricity to rural farms in the 1960s [2].

Turbines got larger as engineers experimented. The first megawatt-scale turbine was the Smith-Putnam machine erected on Grandpa’s Knob in Vermont in in 1941.  It supplied power to Vermont’s grid until it suffered a serious mechanical problem, including a blade failure, which eventually shut down the machine.  More large wind turbines followed, and the first wind farm, albeit with smaller turbines, was erected in Altamont Pass in California in the early 1980s.

But at that time, wind power technology was not competitive with electricity generated from fossil fuels.

Photovoltaic electricity was a late starter.  The initially expensive technology started to become commercialized in the 1960s–mainly for satellites that need low levels of power for long periods of time. In 1958, Vanguard I & II, Explorer III, and Sputnik-3 satellites were launched–each powered by solar PV arrays. In 1959, Explorer VI was launched with an array of 9600 cells.

Terrestrial applications were few and far between because the panels were expensive. Communication systems in isolated areas were an early niche market.  In 1978 a 3.5 kW solar array was installed on the Papago Indian Reserve in southern Arizona—the world’s first village PV system.  Then in 1982, the first megawatt-scale solar photovoltaic power plant started up in Hesperia, California.  The PV panels with a peak output of 1 MW, were installed on 108 tracking structures that kept the panels facing the sun over the course of the day. [3]

The energy transition

Over the last 20 years,  the cost of power from solar energy and wind power has fallen exponentially—to the point where solar and wind technologies are now fully competitive with electricity from fossil fuels, including natural gas.

The declining cost of wind and photovoltaic energy has resulted in the increasing deployment of these technologies, and the investment of very substantial amounts of money in these new technologies .  Wind and solar have been the fastest growing source of electrical energy since at least 2015.

However, the contribution of renewable energy to global primary energy production is still small: In 2016, total renewables accounted for just 12 percent of primary energy production—a long way behind coal, oil and natural gas.

Left to the market as it generally exists at present—meaning with fossil fuels substantially subsidized and their external costs ignored, the adoption of renewable energy at a level comparable to the fossil fuels might take decades—during which time the emission of carbon dioxide, methane and the other greenhouse gases emitted from coal, oil, and natural gas-fired electricity generation is going to drive global temperatures way above the Paris Agreement targets of 1.5 to 2°C.

To learn more about renewable energy go here, and specifically for photovoltaic energy go here

 

 

[1] See: A brief history of hydropower. At: https://www.hydropower.org/a-brief-history-of-hydropower

[2] See the Wikipedia article : Wind turbine. At: https://en.wikipedia.org/wiki/Wind_turbine

[3] See: The history of solar, US Department of Energy/Energy efficiency and renewable energy. At:  https://www1.eere.energy.gov/solar/pdfs/solar_timeline.pdf