An associate recently referred a text book to our attention: Geothermal Power Plants: Principles, Applications, and Case Studies. (A second edition is due to be released this month.)

Have you ever wanted to understand or model hydrothermal reservoir characteristics? Have you ever wanted to simply grok what a hydrothermal reservoir is? Would you like to be able to model/understand the thermodynamic characteristics of a hybrid flash-binary geothermal harvest system? Would you like to know where geothermal plants are installed, their conversion method, and capacity? If you answered yes to any of these questions, then this is the book for you.

DiPippo does an admirable job in making the material accessible to all, yet including the deep technical details and formulae required to perform analysis of geothermal projects.

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Via Renewable Energy Access:

Northern California Power Agency (NCPA) and SPG Solar, announced that they will together to build a 1 megawatt (MW) single-axis solar tracking system that will provide renewable energy to an existing pump station that supplies the NCPA Geysers Geothermal Energy Plant.

The array will be used to collect solar power to pump wastewater into the geysers, which is in turn used to generate geothermal power. The photovoltaic array will start generating clean renewable power beginning in September 2008.

The $8.2 million installation consists of 6,300 solar modules that will produce 2.2 million kilowatt hours of electricity annually. The solar plant will supplant PG&E-provided grid power that had been powering the pumps.

Read more…

NCPA operates two geothermal plants at the Geysers producing approximately 132MW gross, and 120MW net of electricity. In the late 1990’s, in an attempt to regain pressure in the rapidly declining Geysers field, NCPA and other operators at the Geysers entered into an agreement with Lake County to reclaim the treated waste water, pipe it to the Geysers, and reinject it into the reservoir. This is necessary because nearly 70% of the mass extracted from the reservoir is released into the atmosphere during operations of the power plants and natural recharge was not matching the pace of extraction.

The good news is this scheme to replace mined mass has worked; so much so, that Calpine followed suit and created a similar agreement with Santa Rosa. The bad news is, it takes power to move the millions of gallons of water from Lake County to the injection wells. The pipeline is about 30 miles (50 km) and gains nearly 2,000 feet (600 m) in elevation over the course of its run. The load to run the pipeline operations is about 8MW, or two-thirds of the parasitic load borne by the NCPA plants.

So, in practical terms, the application of solar energy to power some of the pumping operations should be characterized as an experiment in multi-dimensional harvest. The other opportunities NCPA and the other Geysers operators have (given the location and transmission infrastructure) are straight-forward bottom cycling using the new generation units from UTC power further harvesting heat from the steam exhaust from the turbines and wind turbine installation. This is the approach Montara Energy Ventures is taking with its Sou Hills Prospect.

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The Geothermal Resources Council has recently made a new resource available for its members. The organization has taken over 3,000 technical articles produced in the GRC Transactions and Special Reports and posted them in a research library. This will be an incredibly valuable resource to those interested in geothermal electricity production.

Access the GRC Research Library.

For no particular reason, here’s a photo of a geothermal plant. Enjoy!

Soda Lake Geothermal Plant

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The Geothermal Energy Association, a group that is effectively the geothermal industry’s lobby in Washington, D.C., is sponsoring another Development and Finance Workshop. We’ve attended two of these and can say, for people trying to break into geothermal, they’re a value-added event. Also, like all of these events, it’s proven to be an excellent networking opportunity. This one will be in Las Vegas at the Bally Hotel, Wednesday, January 16, 2008. The session runs from 8-5 and a reception follows.

Session Topics:

• The outlook for state renewable energy laws, federal tax incentives, and other key incentives for expanding geothermal energy production in the West.
• New avenues for financial support of geothermal projects – green power, climate credits, and other approaches.
• Geothermal investing from a variety of viewpoints, including the financing, investing, and marketing of new projects.
• Geothermal project development basics from leading project developers.
• New projects under development: what, where and by whom.
• Geothermal resources in the West – overview and key issues to address for development

So, if you’re interested in geothermal project development and you’d like to get a jump start, we recommend attending this workshop.

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Have you ever wondered why geothermal goes so incognito when the renewable electricity market is so visible? There could be a number of reasons, but we believe it has to do with accessibility to the public and ease of identifying resources.

Photo Credit The Pennine Way

When a lay-person sees the tree above, they can easily posit that wind contributed to the unique shape of the tree. And, since we know generally how trees grow, it’s easy to deduce that there is strong, consistent wind current present in that area. Thus, when people think about wind as a renewable resource, it’s accessible. There is no magic: wind exists and like a child’s pinwheel, it can cause things to move which is sufficient to make the connection.


Photo Credit The Safari Company

When a lay-person sees the photo above, they can reason that it is dry and that it’s likely that the sun shines there on a routine basis and rain/cloud cover aren’t the norm for the region. The connection between a strong sun presence and the potential for energy is very clear to humans, it’s accessible.


Photo Credit: UNR

Now contrast the image above with the tree and desert. What do you observe about the physical characteristics of this land? Does it look like this might be a place one could harness natural resources to generate renewable electricity? This photo happens to be from Nevada’s Dixie Valley, a known geothermal resource area. There is a functioning 60MW geothermal plant in close proximity. The only surface manifestations of the energy potential are hot springs. It’s much less accessible to a lay-person thinking about hot, fractured rocks with super-critical heated water trapped under a cap rock waiting to escape. Can you visualize it? Unless you’ve been around the industry or have a geology background, the chances are that it’s tough to comprehend.

The journal Live Science took a page from VH1’s “Where are they now?” publishing an article on “Whatever happened to Geothermal?” It’s an interesting article and covers many of the issues. Given that geothermal is the only baseload renewable power source (yes gravity hydro is close, but until droughts are solved, it’s not quite baseload) it seems inevitable that geothermal will be “rediscovered” as an energy source.

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