Geothermal energy certainly doesn’t have the popularity of wind and solar power, but it is another great, cheap, renewable energy option that deserves a lot of support. The Geothermal Energy Agency (GEA) recently released a document on 10 reasons to support geothermal energy [PDF]. The full document includes a lot more pictures and several maps or charts, but the text of the document with info and commentary on 10 geothermal energy advantages is here if you just want to have a look at that (note: some of the most important images are included below):
1. Geothermal Power is Reliable Power
Utility-scale geothermal power production adds reliability to the power system. Geothermal power can be produced as a baseload renewable energy resource, meaning it operates 24 hours a day, 7 days a week regardless of changing weather, providing a uniquely reliable and continuous source of clean energy. As a baseload power source, geothermal is well suited as a substitute for coal in our utility system.
Or, geothermal power can be flexible to support the needs of intermittent renewable energy resources such as wind and solar. Because geothermal energy can also be ramped up or down depending on need, it can be used to supplement the integrity of the power grid, enhancing the efficiency of the entire system while providing clean, reliable power.
Geothermal is also capable of achieving high capacity factors – a measure of actual output over a period of time – usually at or above 90%, which is on par with, or higher than, other baseload power sources such as coal-fired or nuclear power plants, and much greater than intermittent sources.
Geothermal power production is also scalable. Power plants as small as a few tens of kW can be economically built for applications in communities, while utility-scale facilities on the multi-MW scale are common.
2. Geothermal Power Creates Jobs and Spurs Economic Growth
Geothermal projects provide economic growth and jobs, often in rural areas with high unemployment. For example, CalEnergy has plans to build a new power complex in Imperial Valley, California, one of the state’s highest unemployment areas. The project will mean investment of nearly $1 billion which will be a boost to the local economy. The project will take almost four years to build, during which time an average of 323 construction workers will be employed. When the project is completed, it will require 57 full-time positions for operations, engineering, maintenance, and administration. This 235-MW geothermal plant compares favorably with either a gas or wind project, which CalEnergy notes would each require about 18 full-time employees for a similar size project.
GEA has identified the following different types of jobs created by the geothermal industry during project development. This does not include the many jobs involved in manufacturing operations, controls, and other components of a power plant.
And while, today, geothermal projects are largely concentrated in the Western U.S., the economic benefits translate nationwide. In 2010, geothermal companies purchased goods and services from vendors in nearly every state.
3. Geothermal Energy Promotes National Security
Geothermal energy is a domestic energy resource that does not require carbon-intensive fuel to operate. Geothermal power can displace use of fossil fuels, thereby reducing our reliance on foreign fuel markets. Also, as electricity becomes a larger part of our transportation system, it can directly displace imported oil. Direct use of geothermal heat for certain commercial, industrial, and agricultural uses, provides an alternative to other sources of thermal energy, including electricity, natural gas, propane, or oil. By increasing the availability of indigenous fuels in the U.S., geothermal can improve our ability to control our economic future and improve our national security, while conserving our available oil and natural gas resources for high-value uses, such as liquid fuels for transportation, chemical feedstock, and pharmaceuticals.
4. Geothermal is Environmentally Friendly
Geothermal power plants involve no combustion, unlike fossil fuels plants, so they emit very low levels of greenhouse gases. Binary geothermal plants, which currently represent around 20% of all geothermal plant capacity in the U.S., along with flash/binary plants, produce nearly zero air emissions. Even dry-steam plants are considered environmentally benign compared with fossil fuels. According to the Nevada Geothermal Council, the state’s 300 MW of geothermal power alone save 4.5 million barrels of oil (the equivalent fuel used by 100,000 cars) and avoid emissions of 2.25 million tons of CO2 annually. Geothermal heat pumps, which are used to heat and cool buildings, are also considered to be one of the most efficient heating and cooling systems available – because of their very low electricity demand, their use greatly reduces emissions resulting from power generation. Additionally, geothermal energy has a very small land-use footprint – among the smallest, per kilowatt of ANY power generation technology, including coal, nuclear, and other renewables.
5. Geothermal is Increasing U.S. Exports Abroad
The U.S. geothermal industry considers itself the world leader in geothermal energy technology. The U.S. has over 3,000 MW installed geothermal capacity – more than any other country in the world – and this number will continue to grow in the coming years. According to the Department of Commerce, geothermal is one of only two renewables that exports more than it imports in the United States. Geothermal equipment manufacturers and service providers exist in almost every state and are able to provide jobs in places like Kentucky or Oklahoma and then export their goods.
6. Geothermal Supports Local Economic Development
Since geothermal resources have to be cultivated locally, geothermal development brings significant economic advantages to local economies. Besides providing a variety of jobs to individuals in these areas, geothermal developers are often the largest taxpayers in the communities in which they produce geothermal energy. In addition to the economic development associated with plant construction and operations, many geothermal developers also voluntarily contribute to the local community. The Nevada Geothermal Council notes that Nevada’s geothermal power plants pay sales & use tax, property tax, net proceeds of mine tax, modified business tax, bonus lease
payments, royalties to the state and county, salaries and benefits to employees, and a range of local vendors for products and services.
7. Geothermal is a Versatile Energy Resource
Geothermal is available everywhere in various forms. Geothermal power production, as discussed previously, provides reliable baseload power to the electricity grid and geothermal heat pumps are heating and cooling homes and businesses in all 50 U.S. states, and around the world. Geothermal energy can also be used for agricultural purposes in greenhouses, to de-ice sidewalks, for food dehydration, and in spas, among other applications. Plus, in many areas, natural geothermal systems are just plain cool to look at: Old Faithful, a natural geyser at Yellowstone National Park, is a huge tourist attraction.
8. Geothermal Makes Good Economic Sense
Geothermal projects produce energy for decades at stable, affordable prices. Viewed in terms of life-cycle costs, geothermal power is economically attractive, providing the lowest cost renewable power and providing long-term fixed power prices. This also reduces price volatility, helping to avoid price spikes and energy crises, which can impose severe economic penalties on business and local communities. Also, in some localities, development of geothermal energy can free up more portable and valuable resources for higher-markup export to other markets or overseas. For example, there is no global commodity market for the hot brine used for geothermal energy production, so its use can allow a locality or national economy to export portable energy fuels – gas, oil, coal, biomass – that are readily marketable elsewhere. It also works in reverse: intensive use of geothermal energy in isolated or island settings can avoid the need to import highcost fuels from other locations.
9. Geothermal Uses Humanly Approachable Technology
Sometimes engineers joke that today’s advanced geothermal plants are at the cutting edge of late 19th-century technology. Now that the laughter has died down, we can appreciate that there’s some useful truth to how straightforward a geothermal power plant really is. While geothermal plant and resource system technology is state-of-the-art, it is accessible to locally trained operators and can be understood and maintained by local workers. Geothermal plants empower operators to become experts in plant function and maintenance, providing communities access to state-of-the-art technology. The mystery to geothermal energy is the enormous resource that the heat of the
earth represents for us to learn to use to meet our energy needs.
10. Geothermal Energy is Widely Available
The heat of the earth is available everywhere. Our ability to utilize geothermal energy is more a question of whether we have the technology to tap this expansive resource. Today, heat can be tapped for heating homes and businesses with geothermal heat pumps nearly everywhere in the U.S., and around the world. Hotter resources are needed for power production, and as technology develops, the areas where power production is economical will expand. In 2011, geothermal power projects were under development in nearly one-third of the U.S. But, as the heat flow map below shows, at a depth of 6km there is enough heat available to provide power from coast-to-coast.
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