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More Solar And Wind Power In The U.S.

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According to the U.S. Energy Information Administration, both wind and solar power are contributing more and more to total electrical generation in the United States.  For the first 8 months of 2019, the combination of wind and solar power accounted for almost 10% of U.S. electrical generation.

Solar, including small-scale PV systems on home rooftops, grew by almost 14% compared to the first eight months of 2018 and accounted for more than 2.7% of total electrical output.  In fact, small-scale solar generation increased by 19% and provided nearly a third of all the solar power in the country. 

Wind energy in the U.S. increased by 4.4%, accounting for almost 7% of the country’s electricity.

Overall, renewable energy sources – which include biomass, geothermal, hydropower, solar, and wind – accounted for 18.49% of net domestic electrical generation during the first 8 months of 2019.  The non-hydro renewable sources actually accounted for over 11% of total electricity production and saw a year-over-year growth of 6%. 

Outside of renewables, nuclear-generated electricity declined by 0.6% and coal power dropped by almost 14%.  Much of the coal generation was replaced by natural gas, which grew by 6.5% compared to the previous year.

Renewables now accounting for nearly 20% of overall electricity generation in the US represents significant progress.  But the variations by state continue to be substantial.  For example, while Vermont gets 99% of its power from renewables, Ohio gets only 2%. 

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Solar and wind energy provide almost 10 percent of total generation in the US in 2019

Photo, posted April 8, 2019, courtesy of City of St. Pete via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Solar And Wind Energy And Groundwater

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The use of both solar and wind farms has been expanding all over the country as a way of lowering carbon emissions from the electric power sector.   According to a new study led by Princeton University, these renewable energy sources have another important benefit:  they keep more water in the ground.

The study focused on drought-prone California where both solar and wind power have been expanding dramatically.  California is the largest agricultural producer in the United States and has also experienced one of the most severe droughts on record between 2012 and 2017.

The study determined that increased solar and wind energy can reduce the reliance on hydropower, especially during times of drought. 

The study looked at multiple scenarios in order to determine how much solar and wind energy should be used to maximize economic revenue and to see how solar and wind power could ensure groundwater recovery.  They created a framework to quantify the optimal pathways for maximizing hydroelectricity and agricultural income while avoiding groundwater depletion.

During the long drought, California’s agriculture industry relied heavily on tapping into groundwater stores, which is an unsustainable practice.  With more droughts likely to occur in California as well as increasing water demand from the growing California population, the burden on the state’s groundwater supply will only grow.

According to the researchers, it is far more practical to impose further regulations on groundwater use if sufficient solar and wind power is deployed.   They caution that these resources need to be deployed long before groundwater aquifers are depleted, or it will be too late for them to do any good.

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Solar and Wind Energy Preserve Groundwater for Drought, Agriculture

Photo, posted December 11, 2014, courtesy of Tony Webster via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Compressed Air Energy Storage

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The increasing use of solar and wind power has created a growing need for technology to store up the energy they generate for use when it is most needed.

Historically, pumped hydropower has provided the largest amount of storage capacity, but it is limited to only certain geographic locations.   Battery energy storage has been growing rapidly, with the technology becoming better and cheaper over time.  But there are various other ways to store energy that have potential and may well find their place in the changing energy infrastructure.

One of these is compressed air energy storage, which has been around for more than a century.  It has been used as a backup method for restarting power plants.  But to date, the economic viability of using it at a large scale has been lacking.

A Canadian startup company called Hydrostor is developing compressed air energy storage technology that it believes can be used on a utility scale.

The way it works is excess renewable energy is used to run compressors that compress air.  Compressing the air heats it up and the heat is captured and stored in insulated hot water tanks.  The compressed gas is then injected into underground caverns.  When energy is needed, the compressed air is released, the stored heat is added, and the warmed gas is run through turbines to generate electricity.  Additional features improve the system’s efficiency.

Hydrostore has built a 1 MW pilot project in Ontario, Canada and is now commissioning a 2MW system as well.  It is funded to build a 5 MW system in Australia next year and it is bidding for 300 MW and 500 MW systems in North America.  The company has received equity funding from Baker Hughes, a large oil-and-gas services and equipment company.

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Storing energy in compressed air could finally become cheap enough for the big time

Photo courtesy of Hydrostor.

Earth Wise is a production of WAMC Northeast Public Radio.

Falling U.S. Carbon Emissions

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Reducing carbon emissions is a goal embraced by nearly every country in the world, but actually accomplishing it isn’t easy. It is true that renewable energy sources are playing a growing role in energy systems, but counterbalancing that trend is growing energy demand, especially in developing countries.

Here in the US, energy-related CO2 emissions actually went up nearly 3% in 2018 compared with 2017.  But the US Energy Information Administration is now forecasting a 2% drop in emissions this year.

The main reason energy-related emissions are headed lower at this point is coal-fired power plant retirements.  More than 90% of the coal used in the US goes toward electric power and utilities are increasingly turning away from coal.

The rapid shift away from coal has mostly been due to the increasing use of natural gas.  Natural gas is not actually a clean and green fuel, but it is definitely less carbon-intensive than coal.  Overall, the total installed capacity of renewable sources – hydropower, wind, solar, geothermal, and biomass – has now actually surpassed the capacity of coal plants.  Given that renewables have in many places become the cheapest power option, there is little chance that coal has much of a future, despite efforts by the current administration.

The electric power sector is gradually moving away from all carbon-emitting sources – a trend that is being reinforced by legislation in many states.  The real CO2 emissions leader is petroleum, which accounts for nearly half of the total.  We have a long way to go to reduce emissions from the use of petroleum.  There are over 250 million cars and trucks on US roads and only a little over a million of them don’t burn fossil fuels.

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US energy-related CO2 emissions expected to fall this year, almost solely due to a drop in coal use

Photo, posted November 6, 2017, courtesy of Cindy Shebley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Lots Of Renewable Energy Jobs

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According to the International Renewable Energy Agency, there were 11 million people employed in renewable energy worldwide in 2018.  This compares with 10.3 million in 2017.  So roughly three-quarters of a million new jobs were added last year.   As more and more countries manufacture, trade and install renewable energy technologies, renewables jobs continue to reach new high levels.

The geographic footprint of renewable energy jobs is changing.  Until now, renewable energy industries have remained relatively concentrated in a handful of major markets such as China, the US, and the European Union.  But more recently, East and Southeast Asian countries have emerged alongside China as key exporters of solar technology.  Malaysia, Thailand, and Vietnam were responsible for a greater share of growth in renewables last year.  Overall, Asia has a 60% share of renewable energy jobs worldwide.

Beyond climate goals, low-carbon economic growth has become a driver for renewables technology.  Renewables deliver on all the major elements of sustainable development:  environmental, economic and social.

The solar photovoltaic industry continues to be the most dynamic renewable enterprise.  It accounts for a third of the renewable energy workforce with more than three million jobs.  

Biofuel jobs were up by 6% to over 2 million.  Wind power supports 1.2 million jobs, with onshore projects predominant.  But the offshore wind segment is gaining traction.  Hydropower is still the largest installed capacity of all renewables but is now only expanding slowly.  The hydropower sector employs 2.1 million people directly, three-quarters in operations and maintenance.

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Renewable energy market employs 11 million in 2018 – IRENA

Photo, posted January 11, 2012, courtesy of the Oregon Department of Transportation via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Our Growing Appetite For Energy

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Energy consumption in the United States set a record high in 2018.  Overall, energy consumption reached 101.2 quadrillion BTUs or quads last year, breaking the previous record of 101.0 set in 2007.  Most of us are not too familiar with quadrillions of anything, nor with BTUs for that matter.  If it is any more illuminating, 101 quads are the equivalent of about 300 billion kilowatt hours.  Our energy use increased by 3.6% from 2017, which was the largest annual increase since 2010.

Wind, solar, and natural gas provided the largest increases in energy supply.  In 2018, solar and wind energy were both up by 0.18 quads, representing a 22% gain for solar and a 7.5% increase for wind.  Over the past ten years, overall renewable energy has doubled in the U.S., with wind increasing by a factor of 5 since 2008 and solar by an amazing factor of 48. 

Natural gas generation increased by 10.7%, or a total of 3 quads over the previous year.   The growth in natural gas use isn’t good news, but since much of it represents replacing coal, it at least corresponds to reduced greenhouse gas emissions.

The unfortunate part of our energy consumption is that the majority of it is still in the form of “rejected energy”.  It most often takes the form of waste heat, such as the warm exhaust from automobiles and furnaces.  The efficiency of our cars, lightbulbs and factories determines how much waste heat is produced and in turn how much fuel and electricity can be put to productive use.

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US energy consumption hits record high in 2018, solar/wind/natural gas grow

Photo, posted April 27, 2015, courtesy of Mathias Appel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Changing Face of Electricity

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The New York Times recently published an article on how electricity is made in the United States on a state-by-state basis and how it has been changing over the past two decades.  Two conclusions to draw are that the mix of energy sources is wildly different from one state to another and that the mix has been changing rather dramatically in many places.

Overall, the past two decades have seen the dramatic rise in the use of natural gas and a dramatic drop in the use of coal.  Coal plants used to account for over half of the electricity produced in the U.S. at the turn of the 21st century.  Now natural gas has passed coal as the largest energy source at roughly 1/3 of the total generated.

Switching from coal to natural gas is a good thing since modern gas power plants emit only about half the carbon dioxide as modern coal plants.  But industry spin about “clean gas” is just spin.  Gas is not really clean; it is just cleaner than coal.  So, having the electric grid powered by gas is not really going to solve our emissions problems.

That being said, there are still states that make nearly all their electricity with coal.  Indiana, Kentucky, Missouri, Utah, Wyoming, and West Virginia are on that list.  Meanwhile, Delaware, Massachusetts, Mississippi, Nevada, and Rhode Island are powered mostly by gas. Idaho, Oregon, Washington, and Vermont rely heavily on hydropower.

Newer renewables like solar and wind are starting to make major contributions in many states.  Wind contributes only 6% nationwide but is much bigger in places like Iowa, Kansas, Minnesota, the Dakotas, Oklahoma and Texas. 

The face of electricity continues to change.

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How Does Your State Make Electricity?

Photo, posted March 5, 2010, courtesy of Tennessee Valley Authority via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Renewables Taking Over In Britain

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A year-and-a-half ago, we reported on the steep decline in the use of coal in Britain, including the conversion of the giant Drax Power Station from burning coal to running on wood chips.  Since then, Britain has been steadily moving away from fossil fuels and towards renewable energy sources.  The transformation is being driven by a surge in offshore wind farms currently under construction or about to begin operating.  Britain is in the process of adding over 6 GW of offshore wind to its current total of 8 GW.  Renewables generated one-third of the UK’s electricity last year, and half of that came from wind power. 

In 2018, coal- and gas-fired power stations generated about 131 terawatt-hours of electricity in Britain.  Renewable energy plants – including wind, solar, biomass, and hydropower – produced about 96 terawatt-hours.  Based on the new projects coming online, renewable sources could generate 121 TWh by 2020 and fossil fuel plants are likely to fall to 105.6 TWh as more coal plants are retired.  Thus, within the next year or so, renewables in Britain are likely to surpass fossil fuels in electricity generation.

The transformation in Britain has been rapid and dramatic.  In 1974, the country generated 80% of its electricity using coal.  By 2016, that number had dropped to 9%.  Last April, the British power grid went three days in a row without burning any coal.  The UK is expected to shut down its remaining coal plants by 2025, if not sooner. 

At the same time, Britain’s renewable energy capacity has more than quadrupled since 2010, jumping from 21 TWh that year to 96 TWh last year.  Britain’s energy mix is changing fast and getting significantly cleaner every year.

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Renewables Could Surpass Fossil Fuels in Britain by 2020

Photo, posted August 2, 2008, courtesy of Richard Allaway via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Electric Cars In Norway

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Norway has long been a world leader in sales of electric vehicles.  The country only has 5.3 million people, so the absolute numbers cannot compete with those of large countries.  Despite that, it wasn’t until the first quarter of last year that Germany became the leader in number of electric cars sold in Europe and Germany has 15 times the population of Norway.

In percentage terms, almost one-third of all new cars sold in Norway last year ran on batteries.  The country offers generous subsidies for buyers who opt to go electric.  The government has set a goal of having all new cars be emission-free by 2025.  Last year, three of the top five most popular new car models were electric:  the Nissan Leaf, the BMW i3, and the Tesla Model X.

Tesla’s Model 3, which has shattered all records for electric car sales in the United States, has yet to go on sale in Norway.  When the car becomes available there in the next few months, it is expected to generate very high sales figures.

The 31% market share for electric cars in Norway far exceeds that of most other countries.  In the United States, for example, plug-in cars account for only about 2% of new car sales.  Only Hong Kong and Iceland are also currently above 5% electric.

Norway’s role in all of this is rather convoluted.  The country has copious hydroelectric power resources that provide virtually all of its electricity.  Thus, electric cars in Norway are truly clean, green vehicles.  On the other hand, Norway is the 15th largest producer of oil in the world and gets about 17% of its GDP from oil exports.  Tackling climate change must ultimately deal with the emissions Norway continues to export.

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Photo, posted October 3, 2018, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Droughts And Hydropower

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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.

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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.

Emissions From Electric Buses

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Municipalities and transit agencies are gradually replacing conventional diesel buses with cleaner alternatives such as natural-gas-powered, diesel-electric hybrid, or fully electric buses.  The goal is to reduce the substantial carbon emissions associated with buses as well as reducing unhealthy air pollution. Diesel buses on average get less than 5 miles per gallon as they transport passengers around, so there is plenty of motivation to find more efficient ways to power them.

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Renewable Energy Jobs

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According to a new report by the International Renewable Energy Agency, more than half a million new jobs were generated by the renewable energy industry last year, an increase of 5.3% when compared with 2016.  The total number of people working in the renewables sector – which includes large hydropower facilities – has now exceeded 10 million people worldwide.

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Renewable Powered Cities

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Cities are responsible for 70% of the world’s energy-related CO2 emissions and it appears that they are taking responsibility for reducing them.  Over 7,000 mayors around the world have signed up to the Global Covenant of Mayors for Climate and Energy, thereby pledging to act on climate change.

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Renewables Beat Out Coal In Europe

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Last year was the first year in which more electricity in Europe was generated from the combination of wind, sun, and biomass than from coal.  The combination of all clean energy sources (which adds hydropower to the mix) surpassed coal several years ago.

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New Milestones For Renewable Energy

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There is no question that solar power has been growing by leaps and bounds in recent years, but whenever one really looked at the numbers, it seemed to still be only a tiny fraction of the country’s power generation – until quite recently, less than one percent.

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Reduced Emissions From Electricity Generation

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A recent report from the Energy Information Administration notes that for the first time in 40 years, carbon dioxide emissions from electricity generation are less than those from transportation.   The reason is that power plants nationwide are abandoning the use of coal and turning to cleaner burning natural gas, as well as newer sources such as solar and wind power.

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Virtual Power Plants

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The traditional model of the electricity grid is one where centralized large power plants send power through transmission lines to substations and then on to homes and businesses.  As localized renewable energy sources, energy storage systems, and efficiency systems proliferate throughout the system, a new concept is emerging:  that of the virtual power plant.

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WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)