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Monday, May 29, 2006

Memorial Day


First of all, I want to express thanks to the men and women serving our country right now. In particular I want to thank those who are risking their lives daily in Iraq and Afganistan. I make no political statement about these actions, but simply express my gratitude to those serving, and urge them to be careful. It is my hope that they each return home safely to their loved ones.

It's common on Memorial Day to reflect on the servicemen who've given their lives in combat. As an ex-submariner I will be remembering those who died in the dark, cold water in the depths of the ocean. As we say in the silent service, they are on eternal patrol.

Countless men lost their lives in submarines in WWII, from all countries that fielded submarines in the theater of war. We must remember them of course.

But there were cold war losses too, which makes the loss of life more poignant. I want to particularly remember these men, whose lives were offered and taken - not in anger, but in horrific way during peacetime. These men's lives ended when they were forced to endure the worst end that a submarine can bring about. Let us not forget them.

The crew of the Thresher:


The crew of the Scorpion:


I also want to acknowledge my fellow submariners who lost their lives on the Kursk:


And finally, the crew of Kosomolets:


Rest in peace, brothers.

Entering the jet age

In 2001 I was ready for a change. Many of my co-workers had vacated the coal-fired facility for brand-new gas turbine combined cycle power plants, and I was keen on getting into this exciting technology.

Note – small gas turbine power plants and turbine-powered gas pipeline compressing stations have been around for decades. A government/industry collaboration to advance gas turbine technology bore fruit in the late 1990’s. This started a massive building boom in large, highly efficient gas turbine plants.

I started looking around, and eventually was offered a position at a large (1048 Megawatt) facility that was then under construction. I went from burning dirt to operating one of the newest and most advanced gas turbines on the planet :) Fortunately it wasn't too difficult of a change, and being fully automated, it was not as challenging as the coal-burner to operate. I also learned that while gas turbine combustion and control logic are exceedingly complicated, the principle of operation is ridiculously simple. While the principle has been understood for a long time, it's only since WWII that practical gas turbines were actually built.

So how does a gas turbine work? As with coal furnaces, there are two major types that differ significantly from one another, although they both use the same principle, the Brayton Cycle.

Below is a diagram showing the four stages of combustion, both for a piston engine (the otto cycle) and a gas turbine (the brayton cycle). The similarities are that air is compressed, fuel is added and ignited, and work is derived from the expansion of the heated gases. The difference is that the piston engine delivers intermittent power, while the gas turbine compresses, burns, and delivers power continuously.



One footnote about the diagram: Most gas turbines used in power generation are not optimized to produce thrust (with one exception that I'm aware of), instead the turbine rotor will have an output shaft that spins at 3600 RPM, turning a generator.

The two types of gas turbines are calle aeroderivative and industrial. It's somewhat self-descriptive, except for the engineering finesse on each design. Aeroderivative engines are gas turbines originally designed for aircraft - they are light, high-revving, easily replaceable machines. In contrast, industrial gas turbines are heavy behemoths that turn at 3600 RPM and are not intended to be removed.

The simpler design, the industrial (or frame) engine, has a single shaft that has an axial compressor at one end, a combustion zone in the center, and a turbine at the exit end. How does it work? The compressor pulls in an enormous mass of filtered air and compresses it. Next, fuel is precisely metered and pre-mixed with the compressed air, and burned in a continuous process. The superheated air expands with great force trough several stages of turbine blades, which convert the expanding gas energy into rotational energy. Because the compressor and turbine are on the same shaft, the turbine provides the energy to drive the compressor, plus has extra power left over to run a generator. The shells on industrial turbines tend to be a couple of inches thick, so that a catastrophic failure will typically be contained within the shell.

In the aeroderivative design there are two rotors. One rotor is high-speed, typically operating at 9500-9700 RPM. This section contains the compressor, combustion zone and a high speed turbine to drive the compressor. In the exhaust path right behind the high speed turbine is a 'power turbine'. The power turbine is connected to a generator that turns at 3600 RPM. As the high speed turbine revs and generates more exhaust gas, the power turbine places more load on the generator. Failures on aeroderivative engines tend to be spectacular - the shells of the engines are light, being designed for aircraft, and when the high speed turbines fail, the blades are thrown at high velocity. Pieces of these turbines are often found outside their protective enclosures following a failure.

The current power plant design is called a "combined cycle" arrangement. In this case we have one or more gas turbines (Brayton Cycle) that operate a generator. The still-hot exhaust gas is then directed into a boiler to create steam and operate a steam turbine (Rankine cycle), increasing power output for the same quantity of fuel burned. Thus we combine cycles! Coupling the cycles yields efficiencies close to 60%. Coal burners and nukes run 30-35% if I recall correctly. Advanced simple cycle (stand alone) gas turbines hit about 40% efficiency.

Sunday, May 28, 2006

Burning Dirt


After a too-long stint at the robust but very simple and boring geothermal plant, I worked at a coal-fired cogeneration plant for a while. This was my only experience with a solid fuel-fired boiler and a hideously complex controlled-extraction steam turbine. Don't let anyone kid you - cogeneration plants that ship steam to sensitive industrial processes are *way* more complex than enormous stand-alone power plants!

Most large coal-fired utility boilers (350 Megawatts and up) use pulverized coal. Wiki has a pretty good explanation of how such boilers work. Essentially the coal is ground up into black flour and transported into the boiler in a stream of hot air, where it ignites like gasoline. In the center of such boilers is a fireball so intense that you need welding goggles to look at it. The disadvantages of burning coal in this manner are twofold: The intense heat generates large amounts of nitrous oxides (NOx), and it's impossible to control the formation of sulfur dioxide (an acid rain precursor), which results from the natural sulfur content of coal.

The facility I worked at used a CFB (Circulating Fluidized Bed) boiler however.
The combustion process occurs at about 1600 degrees F, rather than the 2400-2600 degrees in the pulverized coal process. This greatly reduces NOx formation. Furthermore, in this process limestone is added to the furnace. At this lower temperature it reacts with the sulfur present in coal to form Calcium Sulfate, aka gypsum, the material in drywall board. Definitely a more useful substance than acid rain :)

OK, so how does a CFB differ from a PC (pulverized coal) boiler? I'll explain the combustion air path for both, which should mostly describe the differences.

In a PC boiler, air is drawn in through a Primary Air fan, sent through a rotary regenerative heater, and then on to the coal pulverizers. The pulverizers have ground the coal to fine dust, which is picked up and transported along with the air into the furnace where it burns. The radiant heat from the combustion heats the walls of the boiler which are made of tubes containing water. The water becomes steam to turn a turbine...

Below is a photo of a single burner firing at a *very* low intensity inside a PC boiler. A typical large utility boiler will have 16-20 burners, burning an incredible 100 tons per hour of coal!

In the photo you can clearly see that:
1. The coal is burning rapidly, almost like a liquid
2. The walls of the boiler are made from numerous tubes welded together to form a wall
3. Slag has deposited on the walls of the boiler - at the lower left in the photo, the tubes look 'fuzzy'. This is slag.



The bottom of a PC boiler is... a water trough. Weird, eh? There's a good reason however. All boilers run at a negative internal pressure, so that any leaks will be air leaking in, rather than fire leaking out! Due to the high temperatures involved, minerals present in the coal melt and condense on surfaces inside the boiler. These condensed blobs of fused ash are called "slag" or "clinkers", and they grow larger and larger. Eventually they fall under their own weight to the bottom of the boiler. They are often quite large, and fall a long way (sometimes 10-15 stories, depending on the size of the boiler!). So how can we get them out while still keeping the boiler at a negative pressure and on line? Let them fall into the water and grind them up! Afterwards we can pump out the sludge with a fast-moving jet of water. This stuff is called the bottom ash.

Back to the fire though. The hot combustion gases have to go somewhere. A huge Induced Draft fan pulls the back end of the boiler and keeps the entire boiler at a negative pressure. This draft pulls the combustion gases up, past superheaters. This heats the steam beyond the temperature it was created at, adding to efficiency. The combustion gas then passes down the backpass, where it pre-heats water that is about to enter the boiler, also increasing efficiency. The still hot combustion gas passes through the hot side of the rotary regenerative heater and into (typically) an electrostatic precipitator.

The electrostatic precipitator removes fly ash that was carried away in the draft. The precipitator works by passing the ash-laden gas through a series of high-voltage plates that place a negative charge on the ash particles suspended in the gas.  Next the gas passes into a region where there are positively charged plates.  The negatively charged ash is attracted to the positively charged plates, and sticks to them.  A shaker knocks the accumulated ash from the collection plates from time to time, and the ash falls into a hopper for later removal.

Urea is typically added at this point in order to reduce NOx.   Another retro-fit after the precipitator is usually a wet scrubber.  Here the stack gas passes through a circulating limestone slurry that absorbs most of the sulfur. The cleaned gas now passes through the Induced Draft fan and out the stack.   The steam plume coming from stacks of large coal-fired plants is an indication the hot gases are evaporating steam from the wet scrubber.   It's not harmful and it's cleaner than sulfur-laden combustion gas :) Whew!

On a CFB, things work a little differently though. Here is a diagram of how it works:


The air flow path is different here: Air is drawn in through a primary air fan once again, but this time goes through tubular air preheaters in the backpass. The primary air, now at 420 degrees F is blown into a grid at the bottom of the boiler. The purpose of the grid is to distribute the air and suspend the coal off the floor of the boiler. This is the "fluidized bed", a blend of ash, chunks of coal and granulated limestone. Underneath the fluidized bed, there is positive air pressure, yet throughout the remainder of the boiler pressure is negative.

The combustion process occurs at a much lower temperature than a PC boiler, and it's operationally also a bit sloppier as well. Through the viewport, it looks like a large pool of red-hot lava sloshing around, with the odd firefly of burning coal being sucked up along with the draft. Again, this heat is transferred to tubes in the walls of the furnace to make steam, and as with the PC boiler there is an Induced Draft fan pulling from the back.

Because the coal and ash bed is "fluidized", and because of the airflow from underneath, the bed stratifies a bit. Larger, heavier materials tend to stay near the bottom of the bed, while lighter particles are lofted completely out of the bed by the powerful draft, still on fire! For this process to be efficient, this lost fuel must be recovered and burned. To recpture these unburned particles, very large cyclone separators are used. The combustion gases and particulates go into a cyclone (or several) and are swirled, losing velocity. The combustion gas and minute flyash particles have little mass, so they pass to the center and exit the top. The heavier particles are flung to the outside and fall into return legs that drop them back into the bottom of the furnace for further combustion.

As on the PC boiler, the exhaust gas drops down through the backpass, superheating steam and preheating feedwater for the boiler. Then it goes into a "baghouse" or fabric filter (similar in operation to the bag your vacuum cleaner sports), to remove the flyash. The particle-free combustion gas then enters the the Induced Draft fan, then up and out the stack. Whew again.

The thing about working at the coal burner was how very physical it was. Something was *always* going wrong and spilling a lot of material. If there wasn't an ash leak at the baghouse, there was an ash leak in one of the transport lines. If not that, there would be a coal spill. If no coal spill, the limestone crusher or conveyor belt would dump a couple of tons of limestone. In addition to repairing the problem, you'd have a huge mess to clean up. Then too the control room could be a handful, particularly when something went wrong.

An additional level of complexity was added due to being a cogeneration facility. The steam turbine was able to force half-spent steam out of an extraction point and send it to the thermal host. It was always a tricky process, as this steam was robbed from the places it normally went in the plant - feedwater heaters and the Deaerator.

This facility received large quantities of condensate back from the thermal host - at the wrong temperature and chemistry for the boiler. There was a complex (and failure prone) cooling and treatment system to correct the problems with the returning water.

Coal-fired CFBs are very prone to tube failures, because the ash in the fluidized bed continuously erodes the water wall tubes. The huge airflows required to fluidize several tons of material create turbulence and eddys that contain fine abrasive ash particles. Eventually the ash wears a hole in a tube, and then the furnace must be shut down for repairs. I worked *a lot* of overtime there - a typical year would require 600 hours of overtime per employee.

One thing I liked about this facility though was the culture. We were encouraged to be involved in environmental reporting, maintenance, the chemistry program, and heavily involved in safety. Good thing with the safety program, too. There was a lot of dangerous stuff there - red hot ash, heights, conveyors, coal and ash dust, you name it. It was quite a challenging plant to operate at times - both physically and mentally.

Eventually though, it was time to leave, because a new wave of power plants was being built. Gas turbines!

A final word on CFB furnaces: They are very fuel flexible. A PC furnace can only burn high-quality, low ash coal. A CFB can burn anything solid that will burn - tires, agricultural waste, or coal-mining waste. In this sense CFB furnaces have been providing many eastern coal-mining communities with a valuable service: Eliminating huge watershed-polluting mountains of mine waste while generating electricity from them. A clear-cut case of win-win.

Here's a pitch someone wrote up for burning waste coal.

Here's a plant that accomplishes the process.

And... in the interest of equal time for opposing views, here's a link to an environmental group opposed to burning waste coal (with some seemingly valid reasons). They propose remediation by bringing in non-native grasses that readily grow in coal waste. Could they get out of hand spread, crowding out native vegetation? I dunno! Legacy waste is a pain in the neck, ain't it?

Saturday, May 27, 2006

Geothermal Power



The photo above is one of the facilities that I worked at. It is the three-unit Navy 1 geothermal plant at China Lake, CA. Geothermal energy is fascinating below ground, and fairly mundane above ground :)

Our current understanding of the earth is that there are large tectonic plates, 10-100 miles thick, floating on a liquid magma core of molten rock. Why is the center of the earth so hot? There are three reasons:
1. Residual heat from compression of the earth's mass coalescing to form this planet.
2. Radioactive decay of naturally occuring unstable elements - primarily Uranium and Thorium.
3. Fluid friction as the magma is churned by the rotation of the earth.

Interestingly the earth would be cooled and solid throughout if it were not for #2. But weak and diffuse as the heat generated by the odd radioactive decay is, 100 miles of rock is enough to insulate that heat from being lost.

So how do we take advantage of the trememdous potential of all this heat? Well, it's not so easy, engineering-wise. Even 10 miles of solid rock is a lot to drill down through. Try digging a 6 inch deep hole into a large boulder. Tough, isn't it?

Fortunately there are a few places on the earth where the heat comes to us :) These places are typically where tectonic plates meet. Additionally there are a few places where a plume of magma rises to the surface of the earth without being near a plate boundary. Hawai'i and Yellowstone are two of these. For the most part however magma is closest to the surface near a plate boundary.

Looking at the map in the above link, it looks like there should be plenty of places on the earth where geothermal energy would work well, although it looks like Kansas is probably out of the running :) So how do we take advantage of magma that makes its way near the surface? Well, there's a second caveat: We need to have a hydrothermal resource - a heated underground aquifer.

Water (or steam) is the most effective medium we know of to bring that heat to the surface, and the Rankine Cycle is the best process known to turn steam energy into electricity. Without water, geothermal energy becomes a technical challenge worthy of NASA in the Apollo days.

Below is a picture of how the Rankine, or steam cycle works. In geothermal power, the earth takes the place of the piece labeled "Boiler" ("Qin" is engineering speak for "heat input"). The steam leaves the boiler at the top, travels through a steam line to the turbine at the right, spins it and an attached electrical generator ("Wout"), then the spent steam exits into a condenser, where it is condensed back into water. A feed pump removes the condensed water and pumps it back into the boiler to start the cycle all over again using the same water. In geothermal systems the water is pumped back into the ground.



So now we've seen how the process works, and understand why we need both heat and an aquifer. Let me add two *more* requirements that might not be obvious at first glance: We need the heated aquifer to reside in permeable earth, so that the water or steam can migrate underground to our well, and we also need a large enough aquifer to supply the steam for the power plant we're going to build. Takes a lot of "just right" conditions to make electricity (or building heating) from geothermal. Kind of a bummer, huh?

So how do we develop a geothermal power plant?
We drill a few test wells (for several million dollars each, depending on the depth of the resource). Some wells can be 10,000 feet deep, while others can be as little as 250 ft. Actually it's a little scary knowing that such hot water is at such a shallow depth! Anyway, the wells are flowed for a month or so, while the flow, temperature, pressure, and chemistry are logged. If the resource proves adequate in terms of mass flow and heat content, the developer will try to obtain financing from a very large bank - one that doesn't mind taking some risk on a natural-resource dependent asset.

So how does it all work once the finance is done and the plant is built? There are (more or less) two types of geothermal plants, although both use the same rankine cycle. I'll describe the simpler one first:

The flash type. Water and steam under high pressure and temperature are expelled from the pressurized and permeable rock zone known as a "reservoir" into wells. Several wells bring a superheated water/steam mixture to the surface. The flow from these wells is directed into 'separators' These are the tall structures in the wellfield and power plant in the photo. The purpose of the separator is to separate the steam and water from one another. The steam exits the top, and the water falls to the bottom. The water is re-injected into the wellfield for replenishment. The steam is sent to a turbine. The turbine turns a generator, and voila! Electricity!

The other type of geothermal plant is called a 'binary' unit.
In this case the underground aquifer is either not hot enough to become steam (less than 212 degrees F), or it has so much mineral content that flashing it would precipitate silica and calcium and render the piping systems useless. Here is a work-around for either of those issues.

Assume the geothermal fluid is too cool to flash to steam: The liquid is pumped to the surface, and passed through a heat exchanger. The geothermal water passes through a bundle of tubes which are submerged in a second liquid. This second liquid has a lower boiling point than water, but otherwise behaves similarly in a steam system. In this case the "boiler" in the diagram is actually a boiler. The downsides to binary are two-fold. The secondary liquid is usually flammable butane or pentane, and efficiency isn't as good as with flash types. But considering that there are no fuel costs, efficiency is less of an issue than it would be for a fossil-fired unit.

Of interest is the fluid that is re-injected into the ground! It is quite a bit cooler than the surrounding underground aquifer. It's important to recover as much as possible of the injected fluid, or we run the risk of depleting the reservoir. However, it's just as important that the cold fluid not migrate to production wells too quickly, or it will quench them and cause them to stop flowing!! Significant effort goes into modeling the underground flows of steam and water. Volatile and non-volatile chemicals are injected to determine migration times between injection and production wells. It was a learning process. Eventually injection wells were scattered throughout the producing wellfield, at various depths, and flowrates were adjusted as migration paths and times were better understood. Fascinating stuff!

Nuclear Research Reactor

Photograph of a TRIGA reactor. A clever design that has the ability to be 'pulsed' That is to survive a Chernobyl-type positive reactivity insertion without catastrophic failure.





































The place where I used to live











My home for four years. USS BARB. Nuclear-powered fast attack sub. Seen here in Adak, Alaska in 1986.

Friday, May 26, 2006

Vanity Shot!



I've really gotten very fond of this bike. I had some initial ups and downs with it when I first bought it last year, mainly with fuel delivery and electrical connections. The previous owner was an optometrist (a very nice fellow!) but wasn't mechanically inclined. Now that the reliability issues have been resolved, it's been a very pleasant machine to own.

But there's another bike that's been preying on my mind. This one: The Suzuki GSX-R1000.



I was a passenger on a 2003 model - the owner understandably wouldn't let me take it for a spin on my own. That brief ride was a shattering experience. I've never experienced such powerful and prolonged acceleration in my life. It was still pulling like a freight train when he backed off at 150-ish mph. I'm fairly confident that driving it would be far less terrifying than being a passenger perched on the little pad on the back.

It was a huge adrenaline rush, that's for certain. I'm not sure that a little burst of adrenaline is worth ten grand though. I guess I'll stick with the little workhorse commuter bike for now. Someday though... It's amazing when you think about it for a moment: That ten grand will buy a racing machine that will blow the doors off a high-end Porsche or Ferarri.

Thursday, May 25, 2006

The center stand and other issues

Correct me if I'm wrong, but I was taught that when you stand your motorbike on the center stand, you are supposed to lift the bike while standing on the lever of the stand...

Today I oiled the chain on the KZ650 right before coming to work, so I put it on the center stand. I struggled to get the bike up - with a full tank it's just over 500 lbs that I was trying to lift up. Anyhow, I bent the center stand, because when I rolled the bike forward off the stand, it rubbed against the tire and didn't return to its normal position. I wedged it past the tire and then it rubbed the chain.

It was time to leave for work so I wedged a little piece of plastic to keep it from rubbing anything - expecting the plastic to fall out at any time (which it immediately did). So I rubbed the chain and the tire all the way to work (~35 miles). Just got a little extra groove in the tire. After getting to work I removed the center stand and chucked it in the dumpster. Maybe I'll just use my floor jack with a piece of soft wood on it next time.

I've been trying to get this bike to run better. It's been surging, both at very low speeds and at high RPM. So I used some fine-grit sandpaper to clean up the ignition points (hahaha, yes it actually has a pair of *points* and condensers), and adjusted the gap. I also advanced the ignition timing *a lot*. I'm of the school that you advance it until it pings, then back off a hair until it no longer pings. Well, I didn't advance it quite *that* far, but I did advance maybe five degrees.

It runs like a different machine now. I can now sometimes get it to do a low wheelie by decelerating and then whacking the throttle open. It still surges (and backfires) though, and I have a valve shim kit on order so that I can adjust the valve clearances. This isn't something that I'm keen on doing, especially as there is the possibility of losing valve timing if I screw it up. Considering the difficulty I have with something as simple as oiling the chain, a valve lash adjustment is likely to end in engine scrap :). We will see. The shim kit should arrive next week.

After stewing about the VA debacle with social security numbers, I decided to visit the Veteran's Affairs website: http://www.va.gov/
Which brought me to this:
http://www1.va.gov/opa/pressrel/pressrelease.cfm?id=1126
I note that there is a link to the "printable version". Hahaha. I have an unprintable version... but then I'm an ex-sailor.

Anyway after reading a bit about Identity theft, I was directed to firstgov.
http://www.firstgov.gov/veteransinfo.shtml

And there they suggest checking with one of the three major credit background check agencies: Trans Union, Experian, or Equifax.

I chose Experian, having previously used them to obtain a credit report. Their site suggests that Veterans get a "Initial Security Alert" (90 days) placed on your credit. This requires lenders to follow certain procedures before extending credit in your name. I had them call my cell phone if an attempt is made to extend credit. Here's the description:
https://www.experian.com/consumer/cac/InvalidateSession.do?code=SECURITYALERT

I highly recommend any veteran reading this page take a few minutes and do this! Just click on the "Initial Security Alert" link and fill in the boxes. You will also get a current credit report, so you can find out who's been checking your credit. Capital One has hit mine dozens of times! Looks like they want me to owe them money. Ain't gonna happen! Sorry, but I only do mortgage debt :)

Tuesday, May 23, 2006

Isn't that *special*?

http://news.yahoo.com/s/ap/20060523/ap_on_go_ca_st_pe/veterans_disk

So today I learned that my Social Security number and birthdate were taken home by a data analyst for Veteran Affairs - and then stolen! It *does not* make me feel better that he wasn't authorized to do so. It also *does not* make me feel better that regarding the thieves, "It's highly probable that they do not know what they have.".

What if this rash of burglaries in the analyst's neighborhood are merely cover for the real crime: acquisition of 26 million names and social security numbers. Hmmm, I'd feel a whole lot better if the guy was just a mole working for China or Russia inside the Pentagon.

Anyway, I'm pissed enough about it that I spammed my representatives, then I sent a mass e-mail out to all my ex-military pals, asking them to spam their representatives. I don't normally do things like this, but... c'mon! Oh I can't wait for strange bills to start showing up in the mail. *%#$$^#@$%!!!!

Saturday, May 20, 2006

Meltdown!

Yesterday was the last day of shift, and the last day for one of my two crew-members. Ed's moving on to a "retirement job" - going to work for the state water district at an aqueduct pumping station. Great retirement benefits and easy work. Sounds nice.

Coincidentally it happened to be an abnormally hot and humid day, with very high electrical demand on the grid. The grid operator had requested full output from our facility, which is never an easy task. The gas turbines (which each have their own generator) exhaust into heat recovery boilers to make steam, which turns a steam turbine and generator.

To make additional power, we have four rows of "duct burners". These are large horizontal natural gas burners that are installed in each boiler. Operating duct burners is not as efficient as burning gas in the gas turbine, but you can get extra steam (and power) without the huge capital cost of installing another gas turbine and boiler. We fire the duct burners fairly frequently - more often when it's hot and the compressor efficiency suffers as the air density drops.

Anyhooo... to reach full load, we have to inject a portion of the steam into the GAS turbine compressor discharge. It rams more mass through the turbine, making it produce more torque. Overall the plant loses efficiency, but the power output goes up - as do the maintenance costs. It's kinda like using nitrous on your car engine. Does wonders for power, but your mileage and longevity suffer. Still, if the economics make sense, we inject steam. The last time we had injected steam was nearly a year ago, last summer

So, we had been dispatched to full power, and an emergency dispatch at that. It took about 45 minutes to properly heat the steam supply lines and get the moisture out. None of the valves wanted to work properly, and some of the instrumentation wasn't functioning, so I ran a couple of things in manual. It was kinda challenging. Emissions also get ugly for a while when you mix steam into the combustion picture. Finally we got everything running and stable, and the plant was churning out every megawatt it was capable of, given the high ambient temperature and humidity.

I left the control room in the hands of my other teammate and went to a meeting to say farewell to Ed. About that time my teammate called me back. We had lost the feedwater pump on Unit 1 boiler! The standby pump had just been sent off to LA for repair... ugh! The High and Intermediate pressure steam drums started losing level, and the gas turbine went into a runback. The runback keeps the gas turbine from putting heat in a dry boiler and melting the tubes down.

We got a re-start on the pump, started to to regain levels in the boiler, and ended the gas turbine runback, when the pump tripped again. We learned that the motor was experiencing high temperatures and the motor protective relay was shutting it down. I requested that one of the maintenance guys go pull the inlet filters off the motor in case they were plugged - they didn't. We got a third start, started filling, and terminated another runback on the gas turbine.

Finally the feedwater pump tripped for the final time, and the protective relay locked us out from starting for an hour. Too many starts will overheat the windings, so you only get three per hour. When it locked out, we were forced to shut down the gas turbine. So right when we were needed most, we lost half the output of the plant. Dammit. Worse, I learned later that the same thing happened here last year (except the standby pump was functional then)

I stayed a little late to help the night shift crew bring the plant back up - after the one hour timer had expired and the filters on the motor had been cleaned :). It wasn't too big of a deal as the boiler was still pretty hot. It was also pretty dry. Took a long time to fill after we finally were able to re-start the feed pump.

After work a few of us had a final beer with Ed at the local brew-pub. I got home afterwards, slumped on the couch, totally drained, and fell asleep right there.

Friday, May 12, 2006

Yesterday's sell-off

An article from a far more sophisticated and articulate market observer than I am.

http://www.financialsense.com/editorials/gillespie/2006/0511.html

I'm a dilettante (definition 2) in economics, not a master. I learn what I need to survive and for the simple fun of learning and understanding. Nevertheless, we are all fish swimming through the economy, and it's important to understand the nuances of something that so fundamental to our well-being.

Is it happening now?

The markets were ugly all around yesterday, with the exception of commodities.
The dollar and bonds both got pounded, and equities (again with the exception of commodities producers) got walloped. On huge volume.

So...

Is this just a correction in the "what, me worry" market, or does this mark the recognition that the economy isn't all that great? That's the $64,000 question I'm asking myself.

The market gyrations aren't affecting my net worth - increasing it, in fact. I'm positioned for an ugly bear market, which is where I believe things are headed. While there is some gratification at (maybe) being right, I don't take any cheer from the fact that I'm making money as the economy tanks. I'd rather be investing in small scrappy up-and-coming companies with great products. Unfortunately I don't think the US consumer has the cash to buy those products any longer. Joe six is up to his eyeballs in debt. And unfortunately our economy (70%) is dependent on Joe spending every nickel he can lay his hands on.

The economic recovery from the recession of 2002 is the weakest job creation recovery on record, even with skewed statistics. It's been fueled by debt (private and government), and focused in the real estate sector and service sector (finance, recreation, food services), rather than in manufacturing or tech. So it's also a non-productive recovery. Ugly.

This may be the test that Bernanke will have to pass in order to gain credibility as an inflation hawk. Time to see if the man behind the curtains is in fact a *man* (as opposed to a mouse).

I'm already on the sidelines for the most part, with small positions in GLD, SLV, BEARX, GSK and WMB. WMB performance leaves a bit to be desired, but it's <1% stagflation - which I believe is what we are starting to see.

Why do I believe this is what is happening, in spite of the headlines of great employment, great GDP (gross domestic product) numbers, record corporate earnings, and endlessly low core CPI (consumer price index) numbers?

Let's start with employment. April employment was up 138K. Not stellar - economist's concensus was in the 200K range. Worse, the new "business birth/death" adjustment probably accounted for most of the "new" 138K jobs. Without this adjustment, perhaps *no* new jobs were actually created in April. I'm not able to tell how the adjustment skews the results, but I'm confident that it paints a rosier picture than the reality it is supposed to represent.

Let's look at unemployment. In April it was 4.7%, quite low historically. At this low number (think late 1999 early 2000), employees were asking for and getting raises, perks, stock options, and reserved parking places. This time around it doesn't feel like that, does it? Rhetorical question... The 4.7% figure only includes people who have "actively looked for a job in the past 90 Days". So if you've given up looking for a job that you are qualified for (as opposed to a McJob without benefits), you are *not* unemployed. Congratulations for no longer being unemployed!!! Some conjecture that actual unemployment is closer to 9-10% than to 5%.

GDP is another heavily adjusted statistic, one that states the economy is doing better than it really is. If you are interested, in how it's manipulated, please click the link.

The CPI is one of the most highly manipulated and suspect numbers of the bunch. Energy and food are stripped out (allegedly because they are volatile). Housing cost to the consumer is manipulated by using rent equivalent - why is this so when the government likes to crow that home-ownership is at an all-time record high - nearly 70%? Why are we examining the other 30%?

We all intuitively know that inflation is rampaging. The only things going down or staying consistent in price are the items you don't need - discretionary spending. Flat screen TVs, Laptops, DVDs - things you can't eat or heat with - are going down in price. But... if you have to mail a letter, drive to work, eat, use cable, water, or electricity, prices are going up - often in double digits.

Lastly, I want to point to the decline in the dollar vs. a basket of foreign currencies. There is beginning to be a lack of faith in the value of the dollar. Actually this is a rather short term trend... the lack of faith (and the downward trend) goes back further, and the trend is resuming its path downward. This is the reason that gold (and other commodities, from pigs to oil) is going up in 'price'. Because the $US is seen more and more as monopoly (play) money, rather than value. And this is going to be Bernanke's litmus test.

Will he raise rates as high as they need to go to protect the value of the dollar? Because to do so, he will crush the US economy and the debt-laden Joe Sixpack. Mouse or Man? Time will tell!

Sunday, May 07, 2006

A few days offline

Work:
I'm on shift 11 of 14 straight. Getting a little tired and fuzzy-headed, truth be told! The plant has been offline since Wednesday morning, due to economics, and the need to address the nasty oil leak mentioned earlier on Unit 1 generator...

The economics are poor due to record snowfall in the Sierra Nevada mountains this year. It's difficult to compete with essentially free hydro power - particularly when fuel costs are 70% of the facility budget.

Interestingly, the local earth-fill reservoir has been 'seeping' under the weight of all the water behind it, and they are dumping the reservoir as fast as they can. That is to say, they are barely keeping up with the snow-melt running into it right now. "Seeping" of course, is another word for "leaking", and the fact that they are dumping all that precious water means that those of us who live downstream are probably in some degree of danger. I'll feel better when they get the level down a bit.

The economy:
Can't help the feeling that things are going to crash and burn soon. There's too much going wrong right now, under the surface. The country is in debt, the consumer is in debt, and interest rates are going up, making those debts difficult to service. The US savings rate is negative, and the only reason people have been able to prop up the economy by buying stuff is because they've been refinancing their homes and taking out cash - rather than earning the money before spending it. If (when) the housing bubble bursts, a lot of people will be upside-down on their houses and those with ARMS may get foreclosed on when their loans adjust up.

I quote Henry C K Liu, of the Asia Times:

"Still, interest-rate policy is a double edged sword: it keeps funds from leaving the debt bubble, but it can also puncture the debt bubble by making the servicing of debt prohibitively expensive. To prevent this last adverse effect, the Fed adds to the money supply, creating an unnatural condition of abundant liquidity with rising short-term interest rates, resulting in a narrowing of interest spread between short-term and long-term debts, a leading indication for inevitable recession down the road."

So in short, they raise interest rates, then print more money to make it easier to pay off debt. This will not end well, and it explains why everything is going up in price: Because the dollar is really worth less!

Motorbike stuff:
Been riding to work exclusively. I determined that I save about $9 every time I ride to work vs. driving the truck. Cool! More money for other stuff, then. I tightened the chain and fixed a turn signal problem I was having. Turned out to be a bad ground on the turn signal housing. The entire housing has a rubber snubber to keep the engine/road vibrations from wrecking the filament in the light bulb, and the ground connection wasn't good across the rubber grommet. Took a while to locate the problem, but it was just some mild corrosion.

Exercise:
Got back to it last night for only about 15 minutes, and man am I sore!!! Just did a really mild chest/back/abs workout, and ouch! Legs and cardio tonight.

Tuesday, May 02, 2006

Fear and loathing in Bakersfield

Last night was a good night to forget. We've begun cycling the plant due to poor economics for electricity at night. Last night was our first shutdown to be followed a few hours later by a startup.

The oil leak that I thought I'd fixed in the Humpin' post, I didn't correct. Turns out this leak will require competent millwrights to correct, not a worn out operator. Oil is being flung out along the shaft of the generator past a seal. This assembly was taken apart to inspect the hydrogen seals during the outage, and apparently it's not together quite right.

The upshot is that this leak will continue until further notice, and it's nasty. The shaft is flinging the oil everywhere, and the fan is distributing it as well. It's about 1 inch deep in the compartment each time we shut down. No fun to keep cleaning up the same mess over and over. These GE lube oil systems remind me of older Harleys. No matter what you do, they're going to leak oil, from every flange, valve stem, and tubing fitting.

So last night, shortly after we got the plant shut down, started adding oil to several pieces of equipment. We got a pallet of drums out of the oil storage area, located the necessary hoses and pumps, and started refilling. Meanwhile the steam turbine rolled to a stop.

Unfortunately steam turbines have to be continuously rolled until they cool, and the turning motor failed to start... so we fought for an hour and a half to start the turning motor, while rolling the steam turbine manually, with great effort. The rotating assembly weighs several tons, being composed of a generator rotor, High, pressure low pressure and reheat turbines. Lots of iron and copper to roll over by hand. Couldn't get any electricians to come in and fix it either.

Finally for one reason or another, the turning motor started... but by then the hot steam turbine rotor had bowed. We had eccentricity alarms when the steam turbine first rolled, but shortly before start-up the bowing worked its way out.

Anyway, shortly after getting the steam turbine to roll, it was time to fill the boilers and start the gas turbines! Geez I barely had time to get the feedwater pumps lined up and started before running back to the control room to keep an eye on the startup with the somewhat less experienced dudes I'm working overtime with.

So we started both gas turbines, began developing steam pressure and by the time we met all the conditions necessary to admit steam into the steam turbine, its eccentricity was back to normal. Whew! What a night! Happily we made startup on schedule.

Tasha's gone

I had my cat Tasha euthanized today. She's been sick several times now with kidney infections and her kidneys were failing. Yesterday she began leaking bloody urine - so I got up early before night shift and took her to the vet. She's also been having behavioral issues - crapping more often on the carpet than in her litter box. I wasn't keen on letting her destroy the carpet.

The vet said he could cure the latest infection but that she'd be back again soon with another and another... and she's been limping around in pain for quite a while. So I decided it was time to have her put down. You know what's weird? I made what I think is the right decision for Tasha, and I had no problem doing it. I signed the paperwork and sat stroking her while they got the injection ready, with very little trepidation.

I was emotionally cool and detached as she struggled through the final indignity of having her paw shaved. And I was cool right up until the moment she went limp, and the vet said "she's gone". And then suddenly I felt like wailing. I sobbed all the way home - I can't imagine what I looked like if anyone happened to glance over. There was a horrible sense of loss (over a cat) that I can't even begin to explain.

I'm going to miss Tasha. She's been my companion since well before I got married. I explained to my 3 yr old Grace that Tasha had gone to the doctor and that she wouldn't be coming back - that she had gone to sleep forever. Grace at first said a couple of times "Tasha will get better and come home.", to which I said "No, Tasha won't be back", and then finally Grace said, "We can get another kitty!"

So I guess Grace understands that Tasha is gone, in her limited way. As I also am beginning to understand in my own limited way.