Two New Solar Power Plants For California

THE WAY OF THE FUTURE?

Two Companies have announced plans to construct Solar Electrical Generating plants in California, and in this post I will discuss them both.
The plans have been announced with great fanfare, something that will no doubt gladden the hearts of environmentalists in that State, and also have the eyes of environmentalists from other States looking eagerly at them as the buildup in hype gives them confidence that these plants will be an eye on the future of electrical power generation.

However, are they really as good as that hype tends to make us believe?
To that end, let’s put these plants under a magnifying glass to see just how much of the future they really do show us.

There are two plants from two different Companies, but both use the same concept, that of the Solar Concentrating method of generating the electrical power, commonly called Solar Thermal Power.

THE SOLAR CONCENTRATING PROCESS.

This method uses the sunlight which is then focused onto a central point. At that focal point, water in pipes is boiled to form steam, or in other cases a compound, usually a salt of one sort or another, is heated to a molten state, and this molten compound then heats water to steam. Another form focuses the mirrors onto a central tower where the water is boiled or the compound turned to a molten state to then boil the water. The boiled water forms steam to drive a conventional steam turbine which then drives the generator.

The mirrors are called heliostats. Each mirror, or array of mirrors is mounted so that it tracks the Sun during daylight hours, so that the full light is always focused to the one point providing a large heat source to boil the water or the compound.

The drawback with this is that when there is no sunlight the steam cools and then cannot drive the turbine. Because of this, the plants themselves are limited by the size of the generator and the turbine itself.

The turbine is on the same shaft as the generator. The generator rotor spins at around 3600 RPM and the electrically wired magnetic field in that rotor generates the electrical power in the Stator which surrounds the rotor. The turbine is what drives the generator’s rotor, on the same shaft.

As you might imagine both of these rotating parts of this complex are quite heavy, and to drive them at this necessary high speed, there needs to be a large amount of steam present to provide the ‘grunt’ to drive all this.

The advantage of this process over Solar Photovoltaic (PV) is that any cloud that flits across the Sun will not diminish by very much the already heated water that produces the steam. With Solar PV, that cloud over the Sun causes a large drop in output power, and it can be up to two thirds, and it will then take a period of time for the power to build back up in the Solar PV panels. With this solar concentrating process, the steam barely goes off the boil, so the turbine/generator still keeps revolving, and producing near full power.

However, just like Solar PV, on days of long overcast, then there will be not enough sunlight to boil the water to steam, so the plant will not be producing any electricity at all.
The same also applies for when the Sun sets for the day. The steam will still have some residual drive, but not very long after the Sun sets, and then the whole plant will simply grind to a halt, and will not start to produce power until a few hours after the Sun rises again the next morning.

So, even though this process is touted as ‘the way of the future’ these plants will not be producing any electrical power at all, for up to 16 hours out of every 24.

So then having shown the process, let’s then look at these two plants, and decipher what is painted as ‘this way of the future’.

AUSRA KIMBERLINA.

This plant will be at Bakersfield in California.
The process for this plant uses rows of mirrors with pipes at the focal point carrying the water which is superheated to produce the steam.

As is the nature of most of the information detailed from any releases, and from any websites, they are difficult to decipher, and what is highlighted the most is the number of houses it will be supplying, and the number of tons of CO2 it will be saving, things that environmentalists latch onto, because they have no real understanding of what is actually being said, and because of that, the perception is that these plants are in actual fact, the ‘way of the future’.

This AUSRA plant will be generating 5 MW of ‘green power’, and will be supplying ‘X’ number of houses, or, as they so artfully say, lighting up those houses. Does that mean they are supplying full power to those houses, or just the power to run the lighting in them? Is the plant supplying that power for 24/7/365?
Well, no, not really.
The generated power will be supplied to the overall grid, and during operation it will be supplying a minute amount of power, extrapolated out over that whole grid for use by all the consumers, be they household, commercial or industrial areas.

The artfulness is in the interpretation. The actual power delivered to the grid can be calculated. Then, using this figure, they then use the average power consumption in that locality, (in this case California) for an average household residence, and then say that they produce the amount of power that will supply that ‘X’ number of residences. The impression from the interpretation is that the plant can actually supply those houses, but in actual fact, the power is supplied only to the overall grid for that area.

So, then how much actual usable power will they be producing?
That’s a difficult thing to actually find at any of their sites, because they couch that in obscure details and statistics that say a lot, but in actual fact say really nothing at all.
One thing that this site makes great play of is how much electricity is produced over the land area of the plant itself. It makes it sound so good, and in comparison with similar figures from other plants, it may very well be, but that is a distraction really.

The most pertinent fact is this following.
They can produce full power for 1800 full Sun equivalent hours per year. With that full Sun, the plant will be working at its maximum, and even though still producing power in those times where there is less than optimum Sunlight, that power will be less, and only adding minimally to the overall total power supplied to the grid.
This equates to a full Sun efficiency of just on 20%, and with the extra, that total might rise to around 28 to 30% at best, and the mid to high 20′s is pretty much the standard for these types of plant.
Now, what that means is that, when extrapolated out over the whole year, this plant will only be providing electrical power to the grid for 25% of the time. That equates to a daily average of 6 hours, say 7 hours in Summer and 5 hours in Winter for full Sun periods. So, this plant will be providing power (to the grid only) from 10 AM until around 4 PM, and nothing at all outside of those hours.

This AUSRA plant will cost $15 Million.

BRIGHTSOURCE IVANPAH.

This plant is planned for Ivanpah on the opposite side of the Mojave Desert to the Bakersfield plant.

It’s process is slightly different from the other on in that its heliostat mirrors are focused onto a central tower where the boiler is situated.

This plant is planned for three stages, the first being 100 MW of nameplate capacity, as is the second, while the third will be for 200MW, making 400 MW of nameplate capacity in all, and will take probably 8 to 10 years before that full power is being supplied to the grid.
The overall cost is ‘estimated’ at between $2 Billion and $3 Billion.

Again, when viewing figures from this site there is no ‘direct’ figures for actual usable power supplied, just the distracting ‘X’ number of houses, in this case 140,000 homes.
In California, this equates to around 955 Million KWH.
At full power 24/7/365 the amount of supplied power from a 400 MW nameplate capacity plant provides 3.51 Billion KWH per year.
This gives this plant an efficiency rating of around 26%, slightly better that the other plant, leading an informed person to take these figures as quite sanguine at best. Even using those figures, this plant will still only be providing power for an average of 6 hours per day, using the same structural calculations I explained in the earlier example for the other plant.

A SIMPLE COMPARISON WITH A COAL FIRED PLANT.

As an example here, let’s just compare the smaller plant and use the same $15 Million and build a coal fired plant. It will be a small one admittedly, but the comparison when looking at usable power to consumers will be stark indeed, For that $15 million at the average $1500 per KW, the plant will have a nameplate capacity of 10MW, around one twentieth the size of those large coal fired plants. However, a plant even as small as that will be able to run 24/7/365 and will produce power to the grid in the amount of 84 million KWH, eleven times more than the AUSRA plant will produce with the added advantage that it can supply that power for 24 hours of every day, and not just for 5 hours.

CONCLUSIONS.

So, as you can quite easily see from both of these examples, the actual power provided, even though seeming to be quite substantial, is in actual fact, quite minimal, and will still only provide power for a small part of the daylight period of time, and nothing at all for almost 18 hours in every day. The costs are prohibitive, and were it not for both State and Federal Government subsidies, and other considerations, these plants would not be economically viable in any respect.

People are being hoodwinked into believing that this form of supposedly renewable power is the direction we should be moving in, when in actual fact, it will not in reality lead to the closing of one coal fired plant, because these plants (along with those using the Nuclear process) are the only ones capable of supplying power for 24 hours of every day.
These renewable plants also are more maintenance intensive as those mirrors must be kept immaculately clean all of the time, they also have a considerably shorter life span, are infinitely less robust, and by their very nature can only be constructed in areas well away from inhabited areas because they require vast tracts of land, as well as a supply of water that has to be also constructed into these areas. They are also only viable in Southern areas, and there is no way to generate this power in that area and then transmit it to those high usage areas in the North East of the Country.

These types of plants sound so good, and deliver so little, at an enormous cost.

No, these are most definitely not ‘the way of the future’.

Tagged: AUSRA, BrightSource, Concentrating Solar Power, Kyoto, Solar Power Generation, Solar Thermal power

Posted in: America (USA), Climate Alarmists, Climate Change, Environment, Environmental activists, Global Warming, Propaganda