Nuclear Electrical Power Generation – Why The Fuss? (Part 11)

Posted on Tue 08/11/2009 by


Proposed Fourth Generation Nuclear Power Plant. Image courtesy of Australian Government Umpner Report.

Proposed Fourth Generation Nuclear Power Plant. Image courtesy of Australian Government Umpner Report.

This image shows an artist’s impression of what a future nuclear power plant might look like. Click on the image to open it in a new and larger window.

This shows a fourth generation Nuclear Power Plant, and in this case it is a Pressurised Water Reactor (PWR) Power Plant.

The large and highly reinforced concrete encased Containment Structure is mostly underground, separated, and isolated from the electrical generating area of the plant.

The reactor vessel is the orange coloured one, while the yellow structure is the Steam Generator. The steam is then piped to the two separate turbine/generator complexes, again isolated one from the other.

There are other different types of reactors that have been proposed for further use in this sector, and with each new type of proposal, they become even safer.

The perception that we as people would be safer without nuclear power is unfounded, and stems from people’s perceptions of the word ‘nuclear’, and it’s association with huge destructive bombs that cause immeasureable damage on a vast scale.

Every day of our lives, tens of thousands of people attend hospitals where nuclear material is used on large scales for all sorts of routine tests, so in one respect the word nuclear has received widespread acceptance, because nobody ever protests about these tests or out the front of hospitals because they use the nuclear process inside.

Nuclear electrical power generation has been proven to be safer than any form or process for the generation of electrical power, and has started to receive widespread acceptance across the Planet on quite a large scale.

During the 80’s in fact, Nuclear power plants were coming on line at the rate of one every 17 days, and it is projected that as early as 2015, one large nuclear power plant will be coming on line on Earth every 5 days.

A perfect case for all safety aspects being taken into account is for the Diablo Canyon Power Plant at Avila Beach in San Luis Obispo County in California.

Diablo Canyon Power Plant. Image credit marya, and it is a Commons image.

Diablo Canyon Power Plant. Image credit marya, and it is a Commons image.

This is a large image, so click on it to open it in a new and larger window, and then click on the image again for clearer detail. The two Containment Structures are the large white structures with the dome shaped tops.

This plant has been in operation since 1984, and it’s original licence runs until 2025, and will undoubtedly be extended well beyond that date. It is  PWR plant operating two reactors, each driving a 1120MW generator.

The plant sits close to the San Andreas fault line and has been constructed to withstand a magnitude 7.5 (Richter Scale) Earthquake.

I have mentioned in earlier posts that for the overal power supply from Nuclear plants across the U.S. they can operate at a power delivery efficiency rate of around 92.5%.

In the year 2006, Unit one of this plant delivered power to the grid for the whole year at an efficiency rate of 101.2%, proving that these plants can safely run at their absolute maximum for extended periods of time, making them the single most ideal type of plant for delivery of electrical power, and can do this 24/7/365 basis, year in and year out.

That delivery of power is the single most important factor that must be taken into consideration. In an earlier post I dealt in depth with costings factors, and the thought that the huge original outlay for a large nuclear plant must be offset against that delivery of power. The thought that the same money might be better spent on renewable plants is a false belief. Over its lifespan, the nuclear plant will deliver power to the grid of a factor seven to fifteen times greater than for any form of renewable power plant, be it Solar PV, Concentrating Solar or Wind Power, and it will safely deliver that power for 24 hours of every day as opposed to 4 to 10 hours delivery of power from those renewable power plants. Nuclear plants will also not require massive Government subsidies at either the construction end or the power delivery end.

These factors alone tell us in a loud resounding voice that Nuclear power plants HAVE to be left on the table as major options if we are to continue this lunatic rush away from Coal fired power generation.

Load Curves for actual electrical power consumption.

Load Curves for actual electrical power consumption.

In the end, it all comes back to this one very telling image, the one that is the most ignored and discounted. Click on the image to open it in a new and larger window. That is the very simple chart showing load curves for actual power consumption in the U.S. These two curves show that of all the power being consumed in the U.S. from all sectors, nearly 70% of all that power is required ABSOLUTELY, 24 hours of every day. This is the much talked about Baseload Power that those alarmists from the green lobbies so quickly discount as a valid case for argument.


Reactor Refuelling.

This is in the form of a correction. I quoted above that the Daiblo Canyon Plant ran at 101.2% efficiency for delivery of power for the year 2006. I have since been informed that even though that was the case, it would be a rare thing for a plant to run at that level of efficiency. As I mentioned in one of the earlier posts, the fuel rods in the assemblies only last for certain periods of time. Judicious and carefully calculated use might see them lasting for two to three years. To that end, individual rods are not removed from assemblies, rather the rods are carefully used so that they become depleted at around the same rate, and so on with all the assemblies inside the reactor. So, with careful calculation, when it comes time for the fuel rods to be changed, they can change most of those assemblies at the one time. This is the reactor refuel time. The generator is shut down, the reactor turned off, and allowed to reach a temperature where the work can be carried out. The assemblies are then removed to an area still on site at the plant where those assemblies can further cool before they can then be removed to dry storage, as I also explained in an earlier post.

This is what led up to that period of time when the Diablo Canyon delivered that 101.2% delivery of power for the whole year. That unit for the plant is closed down for refuelling. The refuel at this plant was done prior to the yearly stats starting, and the reactor can then run for 18 months until the next refuel, hence those figures for the whole of that particular year when refuel scheduled times of 18 months carried it over that year, so the plant was running without any down time for refuelling during that whole year for power delivery statistics. An interesting thing that arises from this is the ability of the plant to run at full capacity for that whole year with no down time, further emphasising the ability for these Nuclear Power Plants to be able to do this. Try running your car’s engine at maximum revs, and then try to imagine how it would stand up if you were to do that for a year.

This is the last of the posts in this series, and the links to the earlier posts with a brief description are as follows.

Part 1 An introduction to Nuclear Power.

Part 2 The Importance of Base Load Power.

Part 3 Current Power supply from nuclear power for the U.S.

Part 4 Some Common Misconceptions about Nuclear power generation.

Part 5 From the ground to the nuclear fuel, and the assemblies.

Part 6 The nuclear generating process, reaction, and power generation.

Part 7 Existing U.S. Plants and existing plants around the World and planned future Plants.

Part 8 Costing structures for Nuclear plants and costing comparisons with Renewable power plants.

Part 9 The perceived problem of the Nuclear Waste.

Part 10 The perceived problem associated with Nuclear power plant accidents.