Issue Report: Geothermal energy

Should geothermal energy be a major part of plans to combat global warming?

Geothermal power is energy generated by heat stored beneath the Earth’s surface, or the collection of absorbed heat derived from underground in the atmosphere and oceans. Prince Piero Ginori Conti tested the first geothermal generator on 4 July 1904, at the Larderello dry steam field in Italy. The largest group of geothermal power plants in the world is located in The Geysers, a geothermal field in California. As of 2007, geothermal power supplies less than 1% of the world’s energy. Geothermal energy has become the subject of significant debate in recent years due to its possible role as a major alternative energy resource and solution to global warming. Governments are uncertain as to whether they should include geothermal as a major component of their energy and global warming plans and whether they should provide any subsidies to geothermal energy. Many questions must be answered in this debate in order for any such determinations to be made. These questions include: Is geothermal energy helpful in the fight against global warming? Does it emit 0 emissions in the process of transforming geothermal energy into electricity? What about during the process of drilling to tap into geothermal energy or in the process of building geothermal plants and infrastructures? Aside from global warming, does geothermal energy preserve the environment? Is drilling invasive and potentially harmful? Is geothermal energy a long-term “renewable” energy resource? Is it sustainable and economically viable? Is it available with current technologies and scalable in such a way that it can make a significant energy contribution and impact on global warming? Is geothermal a truly abundant and widely available source of energy? Or, are there a limited number of areas available for geothermal development? Does geothermal supply a consistent and reliable source of energy? Can it help cut foreign dependencies on fossil fuels? These questions need to be fully examined before determining the place of geothermal energy in any global warming plan.

Global warming: Can geothermal energy help combat global warming?

Geothermal energy emits no greenhouse gases; can cut emissions

Geothermal energy conversion involves using heat energy from the earth to boil water and drive turbines to generate electric currents. This process of energy conversion emits no greenhouse gases, unlike the burning of fossil fuels (which emits greenhouse gases) to drive turbines and generate an electric currents.

Geothermal replaces oil-heating; helps reduces greenhouse emissions

Oil and natural gas heating of both homes and businesses remains a major emitter of greenhouse gases around the world.

Geothermal energy harmfully releases heat into atmosphere

” Geothermal energy relies on geothermal heat. It transfers that heat to the surface to boil water and generate electricity. Much of the heat is released into the atmosphere through steam. The process releases almost twice as much heat into the atmosphere as nuclear plants. The concern is that the release of this heat will contribute to global warming, particularly if deployed on a large scale.

Geothermal energy cannot scale to significantly cut emissions

In order for geothermal energy to have any significant impact on emissions and global warming, it would have to be able to scale massively and economically. Yet, there are many reasons to believe that geothermal energy cannot scale in this way. See the “economics” section below.

Ecosystems: Is geothermal energy good for ecosystems?

Geothermal energy does not cause acid rain like fossil fuels

Geothermal energy releases 97% less acid rain than a fossil fuel plant.[1]

Geothermal energy does not release any waste byproduct

Geothermal does not produce any waste byproduct, such as nuclear radioactive waste or the biomass waste from producing biofuels.

Geothermal drilling can be regulated to avoid releasing toxins

Geothermal drilling does not inherently release greenhouse gases. This only occurs when poor drilling and extraction practices are implemented. Well-regulated drilling and extraction can ensure that greenhouse gases are not released from the Earth.

The environmental benefits of geothermal outweigh the costs

Even if geothermal has some environmental costs, these costs are minimal, and must be weighed against the alternative of continuing to rely on fossil fuels, which do far more destruction to the environment. Geothermal is a far more justifiable than using fossil fuels, so should be pursued.

Geothermal energy takes less land than other renewables

Geothermal energy requires only a couple of wells be drilled into massive super-heated water reservoirs. This requires much less land than other renewable energy sources.

Geothermal energy drilling and extraction can cause earthquakes

This is mainly a concern with Enhanced Geothermal Systems, where water is injected into hot dry rock where no water was before.

Geothermal drilling can release toxic gases from the earth

"Potential for Renewable Energy in the San Diego Region". August 2005

– “Geothermal development is similar to drilling for oil and gas. It has many of the same environmental consequences if not properly managed.”

Geothermal wastewater contains toxic chemicals

Hot water from geothermal sources will contain trace amounts of dangerous elements such as mercury, arsenic, antimony, etc. which if disposed of into rivers can render their water unsafe to drink.

Economics: Is geothermal energy economical?

Geothermal energy is "free"; requires no purchase of fuel

Fossil fuels must be purchased, then they can be used as fuels to generate power. Geothermal energy is “free” in the sense that it is simply heat from underneath the ground. This heat does not have to be purchased.

Geothermal energy is cost-effective for heating and cooling spaces

Purchasing oil (or gas) for heating means paying for that energy resource. Geothermal, on the other hand, is effectively free

Geothermal energy is flexible, powering homes, towns, and cities

Geothermal cab exist on many levels at a small scale and a very large scale. Other energy resources, such as coal or nuclear power cannot vary in scale in this way.

The geothermal energy industry creates jobs

Like any new industry, the geothermal industry offers jobs.

Geothermal energy can be a source of tourism

Geothermal is an intriguing concept to many people around the world, and has proven a source of tourism where it is located around the world.

Many geothermal engines operate at an inefficient low temperature

Geothermal energy operates at a relatively low temperature (compared to steam from boilers), which by the laws of thermodynamics limits the efficiency of the engine.

Geothermal energy is often too far from populated areas

The development of geothermal reservoirs is often unfeasible because they are too far from major population centers. This adds to the cost of transmitting electricity, which is higher over long distances.

Geothermal drilling can be expensive

It can cost two to three times as much as oil drilling, and current technology limits bore-hole depths to 30,000 ft. A break-through in drilling technology appears necessary to make the various processes economically feasible.

The geothermal energy industry DOES NOT create jobs

The only jobs and technology that geothermal exploitation creates are those “taken away” from the oil exploration. It uses exactly the same technology and qualified personnel that the oil industry uses. This is a zero-sum game.

Stability: Is geothermal a consistent and reliable form of energy?

Geothermal energy is unaffected by changing weather conditions

Many alternative energy sources are dependent on weather conditions. Wind, solar, and hydroelectric are all affected by weather conditions. Geothermal is not, which makes it a useful and stable alternative.

Geothermal power plants work continuously day and night

This makes geothermal energy good for providing base load amounts of electricity. Base-load electricity is what can replace coal and have an major impact on greenhouse gas emissions.

Geothermal energy is simple, proven, and reliable


– “Once in operation, geothermal plants may be the most reliable of all energy production methods. Since they are fundamentally simpler than most other power systems, there is less to go wrong.” The same applies to using geothermal energy at home.

Geothermal is unaffected by fuel price and transport instabilities

Because geothermal uses no fuel, it is unaffected by the problems of unstable fuel prices and the possible disruption of the transportation of fuel.

Geothermal plants often blow-out

Geothermal energy, by tapping into often volatile geothermal energy, can often result in major blowouts. The fires caused by these blowouts have been known to rage out of control for days.

Geothermal sites can unexpectedly run out of energy

"Disadvantages of Geothermal Energy". Clean Energy Ideas

– “Another big disadvantage of geothermal energy extraction, is that in many cases, a site that has happily been extracting steam and turning it into power for many years, may suddenly stop producing steam. This can happen and last for around 10 years in some cases.” This is not good for the markets nor energy consumers.

The output of geothermal power plants degrades over time

This can take place in the span of several years or a decade if a field is poorly managed.

Weather and frosting can impair geothermal energy production

"Geothermal Heat Pump Problems"

– “There could be potential winds and frosting problems related to your heat pump. But that could be avoided by choosing a good location in the first place. The location of the heat pump outdoor has a great impact on its efficiency. Rule is that all outdoor units shouldn’t be facing high winds, as they can cause frosting problems. Therefore, try to strategically place a bush or a fence.”

Availability: Is geothermal abundant and widely available?

No energy source is 100% "available" in all locations

Oil can only be drilled for in certain locations. Coal can only be mined in certain areas. Wind energy and solar energy are ideal only in certain climates. Almost all other energy sources have some kind of locational limitation. It is not unique, therefore, that geothermal energy has certain limitations on where it can be found and exploited.

Geothermal is one of the most abundant sources of energy

"Pros and Cons of Geothermal". Energy Consumers Edge

– “Geothermal resources may outlast the sun. There is enough thermal nuclear energy in our Earth to fuel the engines of civilization for billions of years…Beneath our feet we have more usable geothermal energy resources than oil, coal, gas, and mineable nuclear fuels combined.”

In the United States, for instance, 100 exajoules of energy are consumed every year. There are 14,000,000 exajoules of geothermal energy in the United States available to meet this demand. That means that there is over 100,000 thousand times the amount of geothermal energy in the United States as the US currently requires for its energy needs. Obviously, geothermal is extremely abundant and, thus, available.

Few areas are suitable for geothermal energy development

"Pros and cons of geothermal". Energy Consumers Edge

– “Using current technologies, geothermal power is primarily available where hot magma finds its way close to the surface and heats ground water to usable temperatures above 212F. These hydrothermal hot spots don’t occur everywhere. In the U.S. they are located in the Western States, Alaska, and Hawaii. “

Geothermal exploration and location is difficult

"Disadvantages Of Geothermal Energy". Clean Energy Ideas

– “So, we have established the main disadvantages of building a geothermal energy plant, mainly lie in the exploration stage. During exploration, researchers will do a land survey (which may take several years to complete) and then post their findings to the company that contracted the survey.”

Locating geothermal plants next to volcanoes is risky

"Disadvantages Of Geothermal Energy". Clean Energy Ideas

– “To extract the heat we have to find certain hot spots within the earths crust, these are very common around volcanoes and fault lines, but who wants to build their power geothermal energy plant next to a volcano?”

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