TMCC Geothermal Plant OperatorsProgram (GPOP)

Presentation for ACS Annual Meeting

Anaheim, CAMarch 29, 2011

Prepared byDave Boden and Jim

Nichols

Geology of Great Basin Geothermal Resources

• Two main geologic settings of geothermal systems:– Magmatic– Extensional

• Magmatic systems are found along the margins of the Great Basin and are associated with young (<1.5 Ma) volcanic rocks.– Examples include Steamboat and Coso

• Extensional systems are associated with youthful normal (extensional) faults– Examples include Dixie Valley and Beowawe

Grass Roots Exploration: Recent Geothermal Discoveries

McGinness Hills Tungsten Mtn Pyramid Lake (3 areas) Teels Marsh Rhodes Marsh Silver Springs

Slide courtesy of M. Coolbaugh

What makes the Great Basin So Prospective?

• Crust is being stretched• Results in high heat flow• As crust is stretched rocks break to

make faults which allow for deep circulation of fluids and good permeability

• Seismic activity results in frictional heating

T at 6 km depth

Geothermal Potential of Great Basin (Electrical Production)

• Region has largest number of geothermal power plants (17 facilities w/ current production capacity of about 800 MW)

– As of fall 2010, there are 12 operating geothermal power plants in Nevada with an installed capacity of 433 MW.

– An additional 1200 MW have been confirmed in Nevada and will be online within the next 5-7 years.

– Developable geothermal resources in Nevada is estimated at between 3400 and 4800 MW, which would account for 35-50% of Nevada’s power needs by 2025 (Shevenell and Blackwell, 2011).

• Largest geothermal facility in the region is Coso in eastern CA with installed capacity of about 300 MW

• The largest facility in Nevada is the Steamboat complex, averaging about 100MW

What is needed to make a geothermal resource viable?

• Five main criteria to make a hydrothermal resource economically viable:– Large heat source (either magmatic or

extensional)– A permeable reservoir– A supply of water– A impermeable cap rock– A steady recharge mechanism

Geothermal Education Office

Injection Wells Production Wells

Types of Geothermal Systems and Related Power Plants

• Vapor-dominated– Provide greatest amount of power per mass of

fluid– Most rare (Geysers, CA; Larderello, Italy)

• High-temperature liquid dominated– T ≥ ~200°C– Mainstay of the industry (flash)

• Moderate-temperature liquid dominated– T > ~100 - 180°C– Provide an increasing proportion of power– Binary systems

Program Need• Data from Geothermal Energy Association

shows need of about 1.7 operations jobs per MW capacity. NV has 433MW installed and 2120-3686MW in development.

• Current demand 433 x 1.7= 736 jobs

• Future demand (2120+3686)/2 x 1.7=4935 jobs

• TMCC has responded to this need by developing its renewable energy program and, in particular, the geothermal technician program

Program Description

• The TMCC program is one of only two in the world (the other is in Iceland )

• Train geothermal plant operators for the growth of geothermal plants in the Great Basin, the West, and world

• Offer comprehensive curriculum leading to a two-year AAS degree or one-year Certificate of Achievement

Progress To Date• TMCC wrote and earned a grant from US Dept. of

Energy for $500k in September 2010

• Convened advisory committee consisting of experts in plant operations world-wide. Advisory Committee would provide. . . – guidance to PI

– assessment of the program

– subject matter experts for course development.

• Developed a draft curricula for program

• Wrote course outlines and desired outcomes for five new geothermal courses.

Technical Courses

• Intro to AC controls• Electric Motors and Drives• Intro to Instrumentation• Fundamentals of Industrial electricity• Fluid Mechanics, Hydraulics and Hydrology*• Geology of Geothermal Energy Resources*• Intro to Information Systems• Plan Reading and Specifications

*Courses specific to geothermal plant operators program

Technical Courses

• Well Design and Construction*• Fluids/Piping/Valves/Pumps*• Geothermal

Plants/Turbines/Generators*• Fundamentals of Process Controls*• Finance and Economics of Renewable

Energy• Environmental Regulations

*Courses specific to geothermal plant operators program

Challenges• Each geothermal system is unique• Some magmatically heated systems have high H2S or

SO2 which can produce acidic fluids that are corrosive to pipes, valves, etc.—requiring injection of chemicals into wells to neutralize acidity

• Some high T systems have high dissolved amounts of silica or calcium carbonate that precipitate upon cooling or release of pressure that can clog pipes and valves—requiring the addition of chemical precipitation inhibitors

• Some systems have very high TDS (e.g. the Salton Sea geothermal field) that can be corrosive or lead to heavy scaling from salt and metal precipitation.

• Plant operators need to be aware of these problems and know when treatment or replacement is needed to maintain satisfactory flow and power production

International Activities

• Interest by U.S. State Department and USAID to export program internationally

• Hosted four engineers from African Rift Valley countries for 10 days in October 2010

• Developed plan for international curriculum with an emphasis on distance learning programs to augment the on-site program

Future Needs

• Teaching laboratory to support geothermal courses will include: –Mechanical engineering– Fluid Mechanics – Demonstration area for geothermal

plant components (pumps, valves, turbines, heat exchangers, etc.)

– Lab for Engineering 100 class (Intro to Engineering)

Well 24-5 Upper Steamboat