In what is becoming a common pattern, the US military is actually leading the way in the installation and use of renewable energy. The military has large chunks of space with renewable resources available coupled with enormous utility bills. This combination leads the military to the obvious conclusion that using the renewable resources will free up dollars for use elsewhere.

A long standing example of this pattern is the Coso geothermal installation on the China Lake Naval Station in southern California. Caithness Energy, LLC operates these plants (~260MW) as a joint venture with the Navy using some of the power locally and selling the rest to utilities for general use.

The most recent example comes from the selection of Integrated Solar Technologies to install a solar roof system on a base in the south Pacific by the end of this calendar year.

Solar Roof Installation

Yesterday, US Geothermal was awarded a 45.5MW power purchase agreement from the Idaho Power Company. This deal largely places the output of the Raft River project for the next 25 years. This can only be described as a large step forward for US Geothermal as they continue to develop the Raft River resource.

Fifteen months after agreeing to be acquired by Raser Technologies, and six months after backing out of that deal, AMP Resources has agreed to be acquired by Italian power company Enel. The jewel in Enel’s portfolio is the Larderello geothermal plant which has been in operation since 1906.

The headline on this deal is “Enel buys into US Market with 150MW acquisition of AMP Resources” but this is misleading as headlines can often be. That’s not to say that AMP’s assets are without value, it’s simply overstating what AMP has to justify a wild premium paid for those assets. AMP, according to its website, has the following assets:

• 21MW nameplate Stillwater, Nevada geothermal plant and a second undeveloped anomaly on the lease
• 12MW Cove Fort, Utah lease on 4,000 acres (the plant was closed for upgrade)
• Salt Wells, Nevada lease of 3,000 acres (no plant)
• Surprise Valley, California lease of 5,000 acres (no plant)
• Undisclosed intellectual property related to Kalina cycle binary heat systems

Obviously, there may be other assets AMP has that are not enumerated on their web site, but that is what’s visible. The only functional and productive plant in the portfolio is Stillwater with a nameplate output of 21MW. However, our research indicates the average net output from the plant is on the order of 10MW at any given time due to high parasitic load consisting of cooling and pumping both geothermal resource and working fluid around the plant. A generous valuation for this asset is $30M.

The “brownfield site” of Cove Fort, Utah has much less risk than other undeveloped properties and as such should be assigned more value. It was producing gross 12MW before it was shut down for upgrade. It’s unclear where that project is at present, but until the upgrade is complete, it’s difficult to assign more value than when the plant was operational, call a generous valuation $20M.

That leaves the undeveloped properties including the area in the Stillwater lease that is still untapped. According to a PIER report for the San Francisco Public Utilities Commission from 2004, the Stillwater site has a most likely rating of 32MW gross and if we use the existing plant as the benchmark, we would expect no more than 15MW net to be harvested. This is undeveloped but known resource, a generous valuation is $1.5M.

The other two properties at Salt Wells and Surprise Valley are early development stages, but have their charms like location close to transmission lines and some early exploration and sizing work complete. However, at this stage, generous valuation of these properties taken together is no more than $2M.

Finally, there is the IP and associated products. With the entry of companies like UTC into the binary harvest market, these assets are far less valuable than a few years ago. Between Ormat and UTC, it’s hard to see AMP and now Enel competing effectively in the binary system space. I don’t know how to value this asset, but the total is likely much less than the differential between the purchase price and the sum of the tangible assets enumerated above.

My conclusion is that with a $90M acquisition price tag, Enel has paid a $36.5M, or 40% premium over the intrinsic value of the corporation and assets. Admittedly, that values the IP at $0, but the tangible assets are all priced above at the high end of the pricing spectrum which means that the IP is likely priced appropriately relative to the actual value of the tangible assets. We’ll see if this deal ultimately goes through, after the prior deal fell apart with Raser, there is a precedent and some reason for skepticism.

Disclosure statement: The principals of Montara Energy Ventures hold no shares in and have no other financial relationship with Raser Technologies, AMP Resources, or Enel.

Australian company Green and Gold Energy has put a solar appliance called a Sun Cube on the market. The Sun Cube is an interesting and simple concept. It’s effectively a box with Fresnel lenses on one side and triple junction solar cells on the other. The appliance is mounted on a dual axis tracking system to ensure that the assembly is always pointed at the optimal location to absorb and focus sunlight onto the cells and the whole deal is controlled with an on-board microprocessor.

Here’s a picture of the appliance:


Recently GGE has announced that they’ve been able to get 35.4% efficiency from these units, see the graph below for data on the experiment. Update: May 14, 2007: the efficiency graph has been removed from Sun Cube’s web site, thus we are unsure if this claim still stands. We have contacted Green and Gold Energy directly and asked them to comment on this entry and contribute any material they see fit to assist in clarification.

Update to the Update: May 15, 2007: Greg Watson, CEO of Green and Gold Energy responded immediately to our inquiry. In a nutshell, G&G have changed business strategy from distributed solar installations to concentrated solar installations with utilities. This change was prompted in part as a means to better manage their intellectual property. Mr. Watson says he knows the change in strategy has caused some grief among early adopters, but this is the direction the company needs to pursue.


This could be a good option for home installations, we’ll watch GGE and the SunCube with interest.

“The Department of Energy has not requested funds for geothermal research in our fiscal-year 2008 budget,” said Christina Kielich, a spokeswoman for the Department of Energy. “Geothermal is a mature technology. Our focus is on breakthrough energy research and development.”

This has been widely reported since December, 2006 and is appalling as geothermal power is in no way “mature” and there are still several breakthroughs required to realize the vast potential of harvesting heat from the earth including:

• Deep drilling to 10km
• Warm water harvest (25-75C)
• Engineered geothermal systems

With the change from the mid-term elections, there is still hope the Department of Energy position can be modified on this issue.