Information about Clean, Renewable Energy.

Blog Archives

Ocean Mechanical Harvest in Practice

Turbines loaded on boat for deployment in East River.

From Renewable Energy News:

A pilot project in New York’s East River is evaluating the use of underwater turbines to generate electricity. If the project bears fruit, the technology could have widespread applications. The effort, formally called New York’s Roosevelt Island Tidal Energy Project, is being conducted by Verdant Power and the New York State Research & Development Authority.

As part of the project, Con Edison is using the electricity produced by the turbines to power a grocery store and parking garage on Roosevelt Island, which sits adjacent to midtown and upper Manhattan in the middle of the East River.

Read more…

For information more information on ocean energy harvest, check our archives on ocean mechanical and thermal conversion posted last week.

1 comment

Southern California Edison inks PPA with Calpine

Geysers Power Plant

Edison agreed to buy 225MW of geothermal power from Calpine today, which should help SCE meet the 20% RPS by 2010 along with large, recent wind purchases. The power purchase agreement still needs approval from the California Public Utilities Commission before it can go into effect.

Comments are off for this post

Mechanical Ocean Energy Conversion, Part II

Having already explored Ocean Thermal Energy Conversion and the reservoir approach to mechanical ocean energy harvest, it’s time to look at the wave action harvest technologies and companies.

This is pretty simple, the energy in the ocean (generated by wind, convection, and lunar gravitational pull) is expressed in waves and currents. One can clearly see the power of waves over time by looking at any coastline or by looking at the aftermath of a tsunami.

The methods for harvest of this energy are also pretty simple. In the case of a current, it’s the same as wind, a turbine is used mounted vertically or horizontally which is connected to a generator. A vertical axis ocean turbine from Blue Energy is illustrated below:

Vertical axis ocean turbine

An artist’s rendering of a vertical axis turbine is depicted below:

Ocean vertical axis turbine

These are accessible technologies and familiar to anyone who has ever seen a windmill in operation. There are some other, more exotic harvest technologies though as well. For instance, the oscillating water column, depicted below:

Oscillating water column device

As the wave action occurs, a column of air is compressed in a tight space creating pressure. This air is driven through an efficient turbine as the wave comes in, and sucked back through the same turbine as the wave goes out when a vacuum is created as the wave retreats. This application could be applied on shore or in a floating device.

Another interesting class of harvest device are the pendulors. As the name suggests, there is a pendulum type device that is moved back and forth by wave action. The pendulum (I tend to think of it more as a paddle) is connected to a hydraulic pump which forces a working fluid through a turbine. This application may also be shore-based or floating. An illustration of a shore-based system is available below:

Pendulor device illustration

Since the ocean comprises the vast majority of the Earth’s surface area and has nearly unlimited energy, both mechanical and thermal, it makes sense to explore utility scale harvest of the resource. There are some efforts underway, but they pail in comparison to the amount of money being poured into wind and solar projects. This is an interesting opportunity for the right kind of investor….

4 comments

Court ruling changes economics

From Renewable Energy Access:

In simple terms, the Court rejected arguments by many electric utilities whose power plants were grandfathered into the Clean Air Act, and then maintained that if they upgraded these power plants — they still would not have to meet Clean Air Act standards.

Renewable energy experts hailed the ruling as the first step to force baseload coal plants to invest in meeting emissions standards like all other energy sources — and that these investments will be reflected in increased rates, making baseload renewables such as biopower, concentrated solar, geothermal and wind more competitive.

Read more

Comments are off for this post

UTC scores a big deal

PureCycle Unit
280kw (225kw net) PureCycle Unit

In what must be the largest deal yet for the UTC PureCycle binary power unit, Raser Technologies has placed an order for 135 units for use in its developing projects.

Effectively, UTC is using its experience in the industrial chiller field to run the chiller backwards using the geothermal resource as input. What distinguishes the UTC approach from others is two fold: operating temperature range 74C (165F) to 150C (300F) and modularity. The units are designed to work individually or to be ganged up in pods as large as 40 units with 9MW net output. It’s really a nice product and Raser shows good business sense by heading this direction. And, it’s a really nice endorsement of the UTC product and approach.

Binary harvest unit illustration
Illustration of how a binary unit works

As you can see from the diagram above, the binary unit is pretty straightforward. Hot fluid comes in, the heat is transferred to a working fluid through a heat exchanger, the working fluid vaporizes and drives a turbine, the working fluid is then cooled and returned to be reheated, the geothermal fluid is (typically) injected back into the reservoir.

Changing gears for the moment, this has had some business impact. Let’s look at what this impact has had on Raser’s stock.

Even though this constitutes movement for Raser, the reaction that is occurring in the stock is nothing less than irrational exuberance. The stock is up at the time of this writing over 30%, and that brings a one month run up of nearly 100% in the stock. While I appreciate that Raser is making very important strides in making their geothermal portfolio a reality, the valuation is wildly mismatched to the fundamentals.

Let’s do some math. Let’s assume that Raser can bring on all 30MW of power in 2008, possible, but it will be a push. Using generous assumptions of power sale at $0.07/kwh and a capacity factor of 95% that would yield around $17.5M in gross power sales per year. On the cost side, wheeling, transmission, and congestion costs will be around $0.015/kwh and plant operations costs will be in the $0.03/kwh range leading to a cost of $0.045/kwh. We haven’t factored in SG&A, depreciation, or debt, but my guess is that’s going to be in the $0.015-$0.025/kwh range. Yes, there will be the Production Tax Credit benefit of $0.02/kwh which will effectively make this tax free earnings, but, the net margin will be rather low, let’s say Raser pockets $2.5M/year on this set of assets. At standard power company valuation of 18.3 times net earnings, that would support a $45.75M market cap for this operation – at Ormat valuation (perhaps a closer comp) of 40x net earnings, that would support a $100M market cap.

This entry is not intended to slam Raser, I’m happy to see the company take these steps and roll out press releases every few days, but I think the valuation of the issue is wildly mismatched to reality. Raser sports a market cap of $464M at present (7:30am PDT April 12, 2007.)

Caveat emptor.

Update 4/16/2007: There have been some questions about whether or not this is an attempt to value Raser Technologies as a whole, it is not. The author has no detailed knowledge of the symetron technology that Raser has developed. The only information that the author has is that there is $400,000 of sales to date of the technology with opportunity for wider adoption. Rightly, that technology should not be valued at $0. However, in the author’s opinion, neither does that technology serve to bridge the valuation gap between the current market cap of $400M and the in operation geothermal plant valuation of $100M. So while we’re not attempting a detailed valuation, common sense dictates that a $400k revenue stream, however promising, does not justify $300M in market cap and thus the author sticks to the conclusion that Raser, at present prices, is overvalued. What is a fair value? That would require in-depth knowledge of the symetron technology to derive a valuation and then simple addition to the geothermal operations.

One other topic this initial post did not cover adequately was resource development cost. According to our research, geothermal resources cost between $1.2M on the low end of the range to $6.7M per megawatt. The average price for projects developed in the US over the past 10 years is $4.3M per megawatt. Drilling costs are the major variable in those figures running at around $1,300 per meter. The UTC unit cost (list price) alone is $1.4M per megawatt. Make no mistake, these are expensive projects to develop.

Finally, resource quality comes into play. The lower the temperature the lower the pressure is likely to be in the production wells. That implies pumping to get the resource to the surface for use in the generation units. This increases parasitic loads. The Stillwater plant in Nevada is a 19MW gross operation, but up to 50% of the output is dedicated to parasitic load. So when valuing the 30MW installation, it is likely overly optimistic until a resource review shows that the parasitic load will allow for that output.

There have also been some comments indicating that this source is anti-Raser. That’s simply not the case. Raser, like any other company in this space has a market valuation and an intrinsic valuation. When there is a difference between those two values, it’s interesting to explore. This has previously been pointed out with a Raser competitor, Ormat. Though the disparity between the two values is not so large in that case. The author would like to point out again, that Raser is making good public steps in development of its projects, management seems to be making shrewd choices, and that at the right valuation, Raser could be a good long term investment.

Disclosure: The author holds no shares in UTC or Raser Technologies

3 comments

« Previous PageNext Page »