The Steamboat Geothermal Power Plants were built over the Steamboat Known Geothermal Resource Area (K.G.R.A.). The average geothermal water temperature is 320 degrees F. The SB 1 and 1A plants were built in 1985 and went into commercial production in 1986. The SB 2 and 3 plants were built in 1992 and went into production in November and December 1992, respectively.

There are four individual plants. The 1 and 1A plants are operated as one plant, as are the SB 2 and 3 plants.

The SB 1 plant has seven ORMAT ENERGY CONVERTERS (O.E.C.'s), or turbine generator sets, that make levels one and two. The third level, with two O.E.C.'s, is designed as the SB 1A plant. The SB 2 and 3 plants have two ROTOFLOW TURBO EXPANDERS, or turbine generator sets, each. The turbines, are part of a binary system that is based on the Rankine Cycle. The SB 2&3 system works as follows (SB 1 & 1A is similar):

Hot water is pumped, under pressure, out of the ground and into a series of twelve cascading heat exchangers by nine 430 hp 16-stage pumps. Since the water is kept under pressure, it is not flashed to steam. In the heat exchangers, using the heat extracted from the hot water, we heat motive fluids. When the motive fluids are heated, they are flashed from a liquid to a vaporous state at extremely high pressure. This pressurized vapor rushes through the piping in a systematic manner toward the turbine drive wheels. Once the energy is spent across the turbine drive wheels, the motive vapor is sent to the condenser to be cooled back to a liquid state for circulation through the cycle.

There are a few differences between the SB 1 and 1A plants and the SB 2 and 3 plants. The SB 1 and 1A plants use pentane and ISO-pentane as their motive fluids. The SB 2 and 3 plants use ISO-butane. The SB 1 and 1A plants have 52 condensing fans, while the SB 2 and 3 plants have a total of 240 fans. In addition, the SB 2 and 3 plants have accumulators, temporary storage facilities to hold excess ISO-butane (the motive fluid) until it is recycled through the heat exchangers. The SB1 and 1A plants must depend on the system itself to carry sufficient quantities of pentane and ISO-pentane to service the system. If pentane and ISO-pentane levels fluctuate too widely, the efficiency of the plant is compromised and production levels fall.

The SB 1 and 1A power plants utilize nine 1200 kilowatt turbine generator sets between them, while the SB 2 and 3 plants have two 10 megawatt generator sets each.

Geothermal power plants have no sulfur emissions as opposed to fossil-fuel fired powered plants and there are no nitrogen oxide emissions. When binary geothermal technology is applied (typically when the resource temperature is below 350 degrees F) there are no emissions at all. Because the geothermal fluids are injected back to the periphery of the original resource, at a depth well below ground water aquifers, the life of the reservoir is maintained and there is no danger of ground water contamination.

Only one species of plant that grows in Washoe County is on the endangered species list. Eriogonum Ovalifolium, or Steamboat Buckwheat, is a form of buckwheat that only grows around the Steamboat area.

The reason for this is the unique soil in the area. The soil has very high levels of Calcium Carbonate and dissolved salts. Other plants find it difficult to grow in the soil. If they do grow, they do not thrive.

It is quite possible, the buckwheat, evolved in place right where it is.

During construction of the plants, we worked with the Nevada Division of Forestry and Nature Conservancy to protect the plants. Fences were installed and transplanting was initiated where needed. Currently, anyone entering the lease area is limited to on road travel only.

While the production of electricity is the most common use of geothermal energy production, there are others. Geothermal heat pumps can be used to circulate hot water through the walls and under the floors of homes and offices. Connection of a heating/cooling system can provide heat during the winter cold and cooling during the summer heat. Mining is another industry that uses geothermal heated fluids to recover gold and silver from the rock they mine. Commercial food growing and preparation plants use geothermal energy to heat green houses and dry onions.

Geothermal energy aids in the development of other countries, including the Philippines and Mexico and countries in Central America, South America, eastern Europe and Africa.

Italy, Iceland, New Zealand, Japan, and France, along with the United States, are developed countries already using geothermal energy. Currently, in excess of 2,400 megawatts + of geothermal electrical power are being continuously produced in the United States, enough power to supply the need of 2.5 million people.

Worldwide, geothermal resources furnish nearly 5,800 megawatts + of electrical power in approximately 20 countries. Geothermal energy is found in more than half of the Third-World countries and could be used to power their economic development without adding to environmental stress.

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