hydroelectric

Drought And U.S. Hydropower | Earth Wise

November 29, 2021 By EarthWise Leave a Comment

The ongoing severe drought in the western U.S. has led to low water levels in the rivers and reservoirs that feed hydroelectric power systems. The Energy Information Administration is projecting a 13.9% decrease in hydroelectric generation this year compared to 2020.

Water levels in Lake Powell have fallen so low that it may not be possible to operate the power plant at Glen Canyon Dam starting as soon as 2022. California officials took the Edward Hyatt hydroelectric plant offline in August because of low water levels on Lake Oroville. Washington, the state with the most hydroelectric power generation, has seen an 11% drop in electricity generated to date this year as compared to last year. That state is actually doing better than others in the West, such as California, where hydro generation is down 38%.

Hydropower accounts for over 7% of the electricity generated in the United States. Five states – Washington, Idaho, Vermont, Oregon, and South Dakota – generate at least half of their electricity from hydroelectric dams.

The current decrease in hydropower is alarming, but it is not unprecedented. The more significant question is whether the drop in generation this year is a sign that this power source is declining and becoming less reliable. According to some scientists, the West is in a “megadrought” that could last for decades.

The greater concern is whether the bad years are likely to become more common because of climate change. Climate projections agree that temperatures will continue to rise, but what will happen to precipitation levels in specific places is much less certain. That is what will determine what the future holds for hydroelectric power.

**********

Web Links

Inside Clean Energy: Drought is Causing U.S. Hydropower to Have a Rough Year. Is This a Sign of a Long-Term Shift?

Photo, posted May 7, 2014, courtesy of Tyler Bell via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Renewables Surpass Coal | Earth Wise

July 3, 2020 By EarthWise Leave a Comment

In 2019, energy consumption in the U.S. from renewable sources exceeded consumption from coal for the first time since before 1885. This has come about from a combination of the continued decline in the amount of coal used for electricity generation as well as the continued growth in renewable energy, mostly from wind and solar.

Until the mid-1800s, burning wood was the main source of energy in the U.S. and, in fact, it was the only commercial-scale renewable energy source until the first hydroelectric plants came online in the 1880s. Coal was used as fuel for steamboats and trains and making steel but only started to be used to generate electricity in the 1880s.

In 2019, U.S. coal consumption decreased for the sixth consecutive year and fell to its lowest level in 42 years. Natural gas has displaced much of the energy generation from retired coal plants.

At the same time, renewable energy consumption in the U.S. grew for the fourth year in a row to a record high level, almost entirely as a result of the growing use of wind and solar power. In 2019, wind power surpassed hydroelectric power for the first time and is now the most-used source of renewable energy for electricity generation in the U.S.

Coal was once commonly used in the industrial, transportation, residential, and commercial sectors. Today, in the U.S., it is mostly used to generate electricity, and that use is rapidly declining.

Electricity consumption for 2020 is likely to be anomalous in many ways as a result of the Covid-19 pandemic shutdowns. From all indications, however, the role of renewable energy will only have been increased during the shutdown period.

**********

Web Links

U.S. renewable energy consumption surpasses coal for the first time in over 130 years

Photo, posted July 26, 2013, courtesy of Don Graham via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Coronavirus And European Energy | Earth Wise

April 23, 2020 By EarthWise Leave a Comment

As people all over the world shelter in place and much ordinary commerce and other activities have ground to a halt, there have been big changes in energy usage. With production halted, offices shut down, schools closed, and public transport operated on reduced timetables, the demand for energy has decreased dramatically.

In Europe, as a result of all this, during the first quarter of this year, renewables’ share of total energy production was greater than 60%. Wind farms provided more than 40% of the renewables’ share of total electricity generation. During February, Denmark, Germany and Ireland saw nearly 50% of their electricity demand met with wind power. Hydroelectric power was the second largest source of renewable energy during the first quarter, with Norway providing the largest share of this. In contrast, generation from nuclear plants was at its lowest first quarter figure for the past five years.

The large shift to renewable generation was in great part due to the overall reduction in demand. This impacts nuclear and fossil-fuel generation much more than renewables because those plants can be throttled back or shut down entirely so as not to needlessly consume costly fuels. Generation that runs on sunlight, wind, or flowing water does not require fuel expenses, so it makes sense to prefer them when demand is reduced.

The reduction in demand has in turn had a major effect on fuel costs as oil reached low prices that haven’t been seen in years.

The decline in demand and fuel prices and the enhanced role of renewables are expected to continue in the current quarter as the timetable for renewed economic activity remains unknown.

**********

Web Links

Renewables achieve clean energy record as COVID-19 hits demand

Photo, posted June 25, 2010, courtesy of Martin Abegglen via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wind Power Overtakes Hydroelectric Power | Earth Wise

April 10, 2020 By EarthWise Leave a Comment

In 2019, the amount of electricity generated by wind power surpassed hydroelectric power for the first time, making wind the largest renewable source of electricity generation in the country.

Total wind generation in 2019 was 300 million MWh, which was 26 million MWh more than was produced by hydroelectric plants.

Hydroelectric generation has fluctuated between 250 and 320 million MWh over the past decade. The capacity base has been stable, so the fluctuations were a result of variable annual precipitation. Hydroelectric generation is generally greatest in the spring when rain and melting snow pack increase water runoff.

The growth in wind power is primarily a result of increasing capacity rather than any major fluctuations in wind caused by changing weather. The U.S. added about 10 GW of wind capacity in 2019, making it the second largest year for capacity additions ever, second only to 2012.

Wind energy is an intermittent source, meaning that it isn’t windy all the time. The average annual capacity factor for the U.S. wind fleet over the past decade has been 28 to 35%, meaning that is the amount of energy actually produced compared with the systems running at continuous full power all the time. By comparison, the U.S. hydroelectric fleet operated at 35 to 43% of capacity during that period. So, wind power is actually not that much less a steady source than hydroelectric power.

According to the U.S. Energy Information Administration, the government’s production tax credit, which was extended through this year, means that wind power capacity in the U.S. will continue to grow at a robust pace. Meanwhile, some dams are being decommissioned and there is little new construction in the hydropower sector.

**********

Web Links

Wind has overtaken the top position for renewable generation in the U.S., EIA says

Photo courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Droughts And Hydropower

February 7, 2019 By EarthWise Leave a Comment

Recent droughts in several western states have led to well-publicized problems including wildfires, loss of trees, and damage to crops. A lesser-known impact of drought conditions has been increases in emissions of carbon dioxide and harmful air pollutants from power generation.

When hydropower runs low in a drought, western states tend to ramp up power generation – and therefore emissions – from fossil fuels. According to a new study from Stanford University, droughts caused about 10 percent of the average annual carbon dioxide emissions from power generation in California, Idaho, Oregon and Washington between 2001 and 2015.

Water is used in electricity generation both directly for hydroelectric power and indirectly for cooling in thermoelectric power plants. When water for hydropower comes up short because of drought conditions, natural gas or coal-fired power plants are brought online to pick up the slack.

These drought-induced shifts in energy sources led to an estimated 100 million tons of carbon dioxide across 11 western states between 2001 and 2015. That is the equivalent of adding 1.4 million vehicles to the region’s roadways. California, whose legislature has mandated that the state be carbon-free by 2045, contributed about half of this total. Washington, which is considering a similar mandate, contributed nearly a quarter of the total.

Western states in recent years have suffered intense droughts that scientists expect to become more common as global warming continues to intensify. The new study indicates that in regions where clean, reliable hydropower has been an important part of the energy mix, it will be increasingly necessary to provide clean backup energy sources in order to meet emission reduction targets.

**********

Web Links

Droughts boost emissions as hydropower dries up

Photo, posted March 7, 2016, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Too Much Of A Good Thing

June 10, 2016 By WAMC WEB

Germany has continued to be the most aggressive adopter of renewable energy among large industrial nations. The country has the goal of shifting to 100% renewables by 2050. Its continuing embracing of solar and wind generation resources over the past decade has resulted in renewables supplying a third of the country’s power on average.