Green Propaganda – Concentrating Solar Power Provides Baseload Power

Posted on Mon 11/21/2011 by

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Can Solar Power replace large scale coal fired power?

Some people say yes, but if you are aware of the full range of all the facts, then that answer is, in all feasible reality, then no, it can’t.

Some people have heard that one plant of this nature actually produced power for a full 24 hour period, and have straight away said unequivocally that renewable power actually has reached the stage where it can replace those coal fired power plants, and supply power on a 24/7/365 basis, Baseload Power.

This one plant is the Solana PS-10 Plant at Sanlucar la Mayor in Andalusia Province in Spain. This plant is the one in the foreground of the image below. This plant utilises the ‘Power Tower’ method of generating power, focusing the Sun’s light with mirrors to a point on top of a 380 Foot high tower, (115 Metres) which equates to 40 Stories high.

Solana PS10 Concentrating Solar Power Plant.

People have little understanding of how electrical power is generated, and from that, how it is actually consumed.

There are so many misconceptions, it becomes difficult to try and explain the real truth, especially when there is propaganda being spread about Renewable Power, of how it can provide power comparable to replace the currently existing power from the sources that those Green supporters want shut down, anything that emits the dreaded Carbon Dioxide, (CO2) mainly large scale coal fired power plants.

A great part of this is caused by the spreading of misinformation, and when people who have been taken in already by the desire to do without those CO2 emitting plants see that misinformation, this confirms their belief that some forms of renewable power actually can achieve this.

An example of this is the misinformation regarding Concentrating Solar Power, also referred to as Solar Thermal Power.

This form of power generation uses acres and acres of specially constructed mirrors which focus the light of the sun to a focal point, heating either water or a compound to a molten state. This molten compound then boils water to steam, which drives a conventional turbine/generator complex to generate electrical power.

It sounds like a relatively simple process, but is incredibly complex.

The problem lies in the weight of the generator and its driving turbine. To actually ‘turn over’ that huge weight at the speed required to generate the electricity, an immense amount of steam is required.

To that end, smaller generators are used, and because of that, less power is generated, considerably less power.

Using completely Solar methods only, these types of plant can actually run for some time after the Sun sets, because that compound, while still partially molten can still generate steam to drive the turbine. However, once that compound goes slightly less than molten, it cannot make enough steam to drive that turbine. Plants using this method, can actually run for around eight to ten hours, providing it remains bright and sunny all day. That time is lessened in the Winter Months, and overall, on an average yearly basis, the might provide their full power for around an average of eight to nine hours a day.

There is something that they can do to extend this time.

They can divert some of that molten compound to a heat saving capability, so that some of the compound stays molten for a lot longer.

The advantage of this is that power can be generated for a longer period of time, and this can be extended out to around 15 hours. In fact, in one case, at the height of Summer, and on a clear hot day, one plant in Spain has actually achieved what is perceived as ‘The Holy Grail’, the ability to produce power for the full 24 hours, and it did this on one day.

However, there are considerable drawbacks with this heat retention capability.

One of these is that by diverting the compound to save that heat, then the overall power generation is reduced, and in every case, reduced considerably.

I mentioned the weight that has to be driven, and the use of smaller generators to do this.

Without heat diversion the maximum power that ‘might’ be generated is currently around 250MW. There is some theory that in the future, they may be able to generate more power, but that theory is problematic, and the time frame is in the regions of a decade or so, and that is just to double that to 500MW.

With heat diversion, the power that can be generated is considerably reduced, down to 50MW, and that is not just for the after hours period, but for the whole day, and even then, barely for 15 hours at the absolute best.

In fact that one plant that did achieve power generation for the full 24 hours generated only 11MW in total.

Another drawback of this heat diversion for longer generation is that a plant utilising this is considerably more expensive to construct and keep in operation.

However, what has been latched onto here is not the cost, not the tiny amount of power that is being generated, and not the conditions that this was achieved under.

No, the main thing that green supporters jumped on was the fact that it produced power for the full 24 hours, so now, they firmly believe that this Concentrating Solar method of power generation has reached the stage where it CAN replace those filthy dirty CO2 spewing coal fired power plants.

So then, let’s do a comparison to see if in fact a plant like this can replace coal fired power.

As I live here in Australia, a naturally bright and sunny place, virtually all year round, let’s then replace a large scale coal fired plant with this Concentrating Solar technology.

Let’s chose, um, say, Bayswater Power Station. This ONE plant has a nameplate capacity of 2,640MW of Power, and then see if this one Solana PS10 equivalent plant can replace Bayswater.

Solana PS10 Concentraing Solar Power Plant.

Bayswater has four turbine/generator units and each one generates 660MW. This plant provides huge amounts of power for consumers on a 24/7/365 basis. One generator at a time will be shut down for yearly maintenance, so the plant produces huge amounts of electricity all the time.

The Solar Plant produces 11MW, so we’ll now need to construct 240 of these Solar Plants.

But, wait a minute.

I mentioned above how people have little understanding on how power is actually generated. Any comparison between the total power of the whole plant is false, (the Nameplate Capacity of the plant) as, what is by far the most important thing is how much power is being generated for distribution and consumption. This is dependent upon the Capacity Factor (CF) of the plant, and is worked out on a yearly basis. Remember I mentioned that one large generator can be shut down on a time to time basis for maintenance, while the others still hum along, supplying huge amounts of power for consumption.

This effectively means that Bayswater, while supplying huge amounts of power 24/7/365 is not producing that full power for the whole year. This power for consumption is measured in GigaWattHours, (GWH) and uses an Industry calculation to get this number, the power actually delivered compared with the theoretical maximum possible generation.

Large scale coal fired power generates its power at a CF that ranges between 75 and almost 90% for some of the more efficient modern plants.

Bayswater currently runs at a CF around 75% to 80%, and because of that, it actually generates 17,500GWH of electricity for consumers.

That small Solar plant also has a CF. This is dependent upon Summer and Winter generation hours, bright sunny days, as compared to overcast, raining, etc. Because of this, the CF for this Concentrating Solar Plant is currently 60%, or, on average, around fourteen and a half hours a day. So, this means this one solar plant produces for consumption 58GWH of power for consumption.

So, now, to generate the same amount of power as the ONE Bayswater plant, you will need 302 of these plants. Compare that to the 240 when you just equate that to the up front Nameplate Capacity of the plants.

So, this one plant that on one occasion did actually generate its full power for one period of a whole 24 hour day, cost for construction was 35 Million Euros, which is $48 Million Australian.

So, to generate the same amount of power as the ONE plant, Bayswater, and needing 302 of them, the cost now comes in at $14.5 Billion

It’s easy to quote that dollar figure, because these days that is evidently no object, but consider the number of plants.

302 of them.

Not just the one plant that may take six to ten years to construct, or raise the finance for, or get all the relevant approvals. Each plant typically covers an area of around 90 acres (37 Hectares), so now you will need 27,200 acres (11,200 Hectares) which equates to 43 square miles or 122 Square Kilometres.

302 Solar Plants, just to replace the same power produced from ONE coal fired power plant.

See how ridiculous it now becomes when you actually do try and do a comparison to replace coal fired power with any of the renewables.

You can believe all the hype you want to, but until you are aware of all the facts, it is all just Green propaganda.