Earth Wise

A look at our changing environment.

You are here: Home / Archives for deep

deep

Geothermal energy may be safe

By Leave a Comment

The Trump Administration is outwardly hostile to renewable energy, especially solar and wind power.  Federal support for these energy sources that are by far the most rapidly growing energy sources across the globe is being gutted while fossil fuels are being propped up.

There is also renewed enthusiasm for nuclear power and, somewhat surprisingly, geothermal heat.   Geothermal is a renewable and clean energy source that has long been mostly overlooked and underfunded.  The main reasons are its expense and the fact that its large-scale use is unproven. 

Historically, geothermal energy has relied upon naturally occurring features such as hot springs and shallow underground heat sources.  However, technological breakthroughs that began in 2013 have led to enhanced geothermal systems, or EGS.  EGS makes use of the fact that if you drill deep enough into the earth pretty much anywhere, you will encounter substantial amounts of heat.  EGS plants pump water three miles down or more where it encounters rock that reaches over 500 degrees.  The piping hot water is then brought to the surface where it spins turbines to generate electricity.

Several companies are developing EGS in the U.S.  financed by tech companies seeking power for their AI activities, the Defense Department, and even by fossil fuel companies who use comparable drilling technology for fracking.

The so-called Big Beautiful Bill passed by Congress in July that eliminates tax credits for wind and solar energy preserves tax credits for geothermal projects.

**********

Web Links

Why U.S. Geothermal May Advance, Despite Political Headwinds

Photo, posted September 30, 2019, courtesy of Stephen D Strowes via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A giant underground battery

By Leave a Comment

Two up-and-coming energy technologies are coming together near a tiny town in central Utah.  Outside of the town of Delta, population 3,600, two caverns, each as deep as the Empire State Building, are being created from an underground salt formation to be used to store hydrogen gas.  The gas will be used as a fuel in a new electricity generation plant.

The plant will replace an aging local coal-fired power plant.  The new plant will burn a mixture of natural gas and hydrogen – green hydrogen produced without emitting greenhouse gases. To produce the hydrogen, the facility will operate 40 giant electrolyzers that will use excess solar and wind power generated at times of low demand to split water molecules into hydrogen and oxygen.

The caverns were created by a process called solution mining in which high-pressure water is pumped down into salt deposits that are dissolved. The resulting caverns are 200 feet in diameter and 1,200 deep and lie 3,000 to 4,000 feet below the surface.  Hydrogen cannot escape through the thick salt layers.

The amount of energy that can be stored in the form of hydrogen fuel in these caverns is massive – far more than all the battery storage installed in the U.S. to date.  Chevron has a majority stake in one of the projects and will supply the natural gas.  The facility is expected to go online in 2025.

While this will produce far fewer emissions than existing coal plants, it is not carbon-free.  Currently, turbine technology cannot operate with pure hydrogen fuel.  The Delta plant will run on only 30% hydrogen.  The hope is that turbine technology will improve in the future and permit operation on pure hydrogen.

**********

Web Links

A Huge Underground Battery Is Coming to a Tiny Utah Town

Photo, posted September 9, 2013, courtesy of Scott via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A New Deep-Sea Reef In The Galapagos | Earth Wise

By Leave a Comment

Like in many other places around the world, ocean warming has mostly destroyed the shallow-water reefs in the Galapagos Islands.  The islands are some of the most carefully protected places in the world, but they can’t escape the effects of a warming planet.

Recently, however, scientists have discovered a healthy, sprawling coral reef hidden deep under the sea in the Galapagos.  More than 1,300 feet underwater, the reef extends for several miles along the ridge of a previously unknown volcano in the Galapagos Marine Preserve.

The reef is pristine and is teeming with all sorts of marine life including pink octopus, batfish, squat lobsters, and a variety of deep-sea fish, sharks, and rays.

The expedition that discovered the new reef was led by the University of Essex in the UK.  Prior to this discovery, scientists thought that coral reefs were all but gone from the Galapagos.  A period of ocean warming in 1982 through 1983 wiped out more than 95% of the corals in the archipelago.  Only a few reefs in shallow waters remained.  The newly discovered reefs are sheltered deep under the sea and would have been protected from the deadly heat.

According to the scientists from the expedition, the newly discovered reef potentially has global significance because it represents a site that can be monitored over time to see how such a pristine habitat evolves with the ongoing climate crisis.  Reefs like this are clearly very old because coral reefs take a long time to grow. Finding this one means that it is likely that there are more healthy reefs across different depths that are waiting to be discovered.

**********

Web Links

Pristine Deep-Sea Reef Discovered in the Galápagos

Photo, posted March 28, 2009, courtesy of Derek Keats via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

California Offshore Wind | Earth Wise

By Leave a Comment

Offshore wind has been pretty much a non-starter in the U.S. until recently.  Now there is considerable activity in the Northeast Atlantic with major projects getting started off the coasts of Massachusetts, New York, and other eastern states.  The prospects for wind farms in the Pacific, on the other hand, have been pretty dismal.  There are significant logistical problems posed by a deep ocean floor and also opposition from the Navy that does not want obstacles for its ships.

A combination of progress in floating wind turbine technology and the arrival of an administration highly supportive of renewable energy technology has changed the situation.  In late May, the Navy abandoned its opposition to Pacific offshore wind and joined the Interior Department in giving support to allowing two areas off the California coast to be developed for wind turbines.

The plan allows commercial offshore wind farms in a 400-square-mile area in Morro Bay in central California, and in another area off the Humboldt Coast in Northern California.

The two California sites could support enough wind turbines to generate electricity to power 1.6 million homes.  That would make the California coast one of the largest generators of wind power in the world.  The forthcoming Vineyard Wind farm in Massachusetts is expected to have 84 giant turbines.  The two California sites could hold more than 300 turbines.

The offshore wind industry is booming around the world, especially near the coasts of Norway and the UK, where the water is shallow, and turbines can be anchored to the ocean floor.  By contrast, the Pacific Ocean floor drops steeply from the coastline, making it too deep to anchor wind towers.  The newly emerging technology of floating turbines is the key to establishing offshore wind in the Pacific.

**********

Web Links

Biden Opens California’s Coast to Wind Farms

Photo, posted August 7, 2013, courtesy of Ray Bouknight via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Even The Deep Sea Is Warming | Earth Wise

By Leave a Comment

Approximately 75% of the area covered by ocean is deep, dark, and cold.  This is known as the deep sea.  But even in these remote regions of the planet things are heating up. 

According to a new study published in the journal Geophysical Research Letters, researchers analyzed a decade of hourly temperature readings at four depths in the Atlantic Ocean’s Argentine Basin, off the coast of Uruguay.  The research team selected recording depths that would best represent the average depth of the ocean, which is just over 12,000 feet. 

The researchers found that deep sea temperatures fluctuate more than was previously known.  They also detected a warming trend at the bottom of the ocean.  In fact, all recordings indicated a warming trend of 0.02 to 0.04 degrees Celsius per decade between 2009 and 2019.  This is a significant warming trend in the deep sea because temperature fluctuations are typically measured in thousandths of a degree. 

Researchers say this increase is consistent with warming trends in the shallow ocean associated with anthropogenic climate change.  However, they say more research is needed to better understand what is driving the warming temperatures in the deep sea. 

A better understanding of what is driving these changes could have far-reaching implications.  Since oceans absorb a significant amount of the world’s heat, learning about the oceans’ temperature trends could help researchers better understand temperature fluctuations in the atmosphere as well.

The researchers hope their findings will demonstrate the need to survey deep ocean temperatures annually in order to better identify the long-term trends. 

**********

Web Links

The deep sea is slowly warming

Photo, posted July 1, 2018, courtesy of NOAA Ocean Exploration and Research via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Lake George Health Report

By Leave a Comment

The Offshore Chemistry Program, run by the Darrin Fresh Water Institute at RPI, has been monitoring the deep waters of Lake George in New York for 40 years.  Lake George, nicknamed the Queen of American Lakes, is famed for the transparency of its water and a new report on the health of the lake reveals that it is doing rather well.

According to the report, although concentrations of chemicals and pollutants like salt and nutrients have increased in the deep waters of Lake George, they are still too low to harm the ecosystem at those depths.

The Offshore Chemistry Program studies the lake as part of a collaboration between RPI, IBM Research, and the FUND for Lake George that is called the Jefferson Project.  This long-term commitment provides a wealth of information over time matched by few lake studies in the world.

The recent results show that levels of salt, the nutrient orthophosphate, and chlorophyll have increased substantially over time, but none are yet at a level that will cause harm.

Orthophosphate occurs naturally, but most likely the higher levels are due to improperly functioning septic systems, failing wastewater treatment systems, and stormwater runoff.  The orthophosphate most likely triggered the increase in chlorophyll, which probably is associated with increased density of chlorophyll in individual algal cells, rather than an increase in total algal mass in the lake.

Overall, the results demonstrate the continuing resilience of Lake George to a growing array of stressors.  In nearly 40 years of human activities, the lake has changed in a number of ways, but the changes have so far been relatively small.  With such careful monitoring, we can hope to keep them that way.

**********

Web Links

Four Decades of Data Sounds Early Warning on Lake George

Photo, posted September 24, 2009, courtesy of GPA Photo Archive via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rapid Antarctic Melting

By 1 Comment

The Ross Ice Shelf in Antarctica is the world’s largest ice shelf, covering an area roughly the size of France.  Scientists have spent several years building up a record of how the northwest sector of the enormous ice shelf interacts with the ocean beneath it.  Their results show that the ice is melting much more rapidly than previously thought because of in-flowing warm water.

In general, the stability of ice shelves is thought to be mostly influenced by their exposure to warm deep ocean water.  But the new research has found that surface water heated by the sun also plays a crucial role in melting ice shelves.

The interactions between ice and ocean water that occur hundreds of meters below the surface of ice shelves have a direct impact on long-term sea level.  The Ross Ice Shelf stabilizes the West Antarctic ice sheet by blocking the ice that flows into it from some of the world’s largest glaciers.

When ice shelves collapse, the glaciers that feed them can speed up by a factor of two or three.  None of the collapsing shelves in the past have come anywhere close to the size of the Ross Ice Shelf, which is more than 100 times bigger.

The new study by New Zealand’s National Institute of Water and Atmospheric Research showed that sun-heated surface water flowing into the cavity under the ice shelf near Ross Islands caused melt rates to nearly triple during the summer months.  This indicates that the loss of sea ice resulting from climate change is likely to increase melt rates in the future.  While the Ross Ice Shelf is still considered to be relatively stable, the new findings show that it may be more vulnerable than previously thought.

**********

Web Links

Rapid melting of the world’s largest ice shelf linked to solar heat in the ocean

Photo, posted February 15, 2009, courtesy of Alan Light via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

WAMC Northeast Public Radio

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