Difference between revisions of "Is Nuclear Power Globally Scalable? by Derek Abbott"

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Jacobson's estimate is larger than the largest figure calculated by [https://books.google.co.uk/books/about/Power_Density.html?id=Mj87CQAAQBAJ Vaclav Smil] for 1{{sp}}GW of nuclear reactor power. Smil's figures range from 0.61 to 13.6{{sp}}km<sup>2</sup>.
 
Jacobson's estimate is larger than the largest figure calculated by [https://books.google.co.uk/books/about/Power_Density.html?id=Mj87CQAAQBAJ Vaclav Smil] for 1{{sp}}GW of nuclear reactor power. Smil's figures range from 0.61 to 13.6{{sp}}km<sup>2</sup>.
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== The Embrittlement Problem ==
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Abbot claims that neutron embrittlement of metal surfaces will require reactors to be limited to 40-60 years lifetime, leading to a requirement that one nuclear power station will need to be built and another decommissioned every day. However alternative technologies also have limited lifetimes. The biggest CSP plant to date is [https://en.wikipedia.org/wiki/Ouarzazate_Solar_Power_Station Noor] in Morocco which has just over half the output of Abbot's notional 1{{sp}}GW nuclear power stations, but at a far lower [[capacity factor]] - possibly 1/3 for ideal locations, or less. Assuming a Noor-type CSP plant has a similar lifetime to a nuclear plant we would have to be building and decommissioning 3 of these every day. Phase I of Noor has half a million mirrors.
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== The Entropy Problem ==
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Abbot states that "In the same way that any electrical device or machine heats up and eventually fails, the same is inexorably true for a nuclear station." Why this is supposed to be a limitation for nuclear power stations and not other machines which heat up (and/or are subject to other stresses) and fail, such as concentrating solar power stations with millions of independently steered mirrors operating under hot and dusty desert conditions, Abbot does not make clear.

Revision as of 01:16, 1 August 2020

"Is Nuclear Power Globally Scalable?" is a "Point of view" article by Derek Abbott, published in in the Proceedings of the IEEE in October 2011.

Derek Abbott starts by asserting that "robust debate" exist "over climate science and remaining oil reserves". This statement is at odds with the scientific consensus on climate change and characteristic of the so-called "merchants of doubt" who seek to cast doubt on the strength of the consensus.

The gist of Abbot's opinion piece is conveyed by his statement:

Given the awesome power density delivered by nuclear stations, it is a valid question to ask if nuclear power can be massively scaled in order to meet our global energy needs. We shall explore the consequences of a future where nuclear power is the main energy source. Currently, the total global power consumption by mankind is about 15 terawatts (TW) - so the question we address is: Can nuclear power feasibly supply at least 15 TW?

Abbot proposes that any technology which cannot supply 100% of the planet's needs is of little use and "major investment" should be reserved for a technology which could supply 100%.

If we can show that nuclear power can viably provide massive power at this level, for millennia to come, then the investment in improving and scaling-up nuclear technology is justified. However, if we find it does not scale up, then major investment must be redirected to a different solution that is truly scalable.

This view is not supported by the findings of IPCC WG3 who find that we need multiple clean energy sources - renewables, nuclear, and CCS - for effective climate change mitigation.

Abbot continues:

It has been argued that the one renewable energy solution that is scalable well beyond 15 TW is solar thermal technology[5] - this is where large mirrors are used to focus sunlight to heat water thereby creating superheated steam, which can then generate electricity via a conventional steam turbine. The potential is enormous, as the amount of solar power that reaches ground level is 5000 times our present world power consumption. Therefore, the pertinent question is to ask how nuclear power compares to solar thermal power as an energy resource on a massive global scale.

The reference [5] which Abbot gives for his assertion that concentrating solar thermal electricity generation (CSP) is a scalable alternative, is to a paper of his own, "Keeping the Energy Debate Clean: How Do We Supply the World's Energy Needs?". In this paper Abbot finds that CSP alone, with a variety of storage and energy transfer mechanisms, can supply all the world's needs. This finding is not supported by the IPCC's assessments.

Abbot proceeds to identify and discuss various issues which he identifies as

  • I. THE NUCLEAR SITE LOCATION PROBLEM
  • II. THE LAND AREA PROBLEM
  • III. THE EMBRITTLEMENT PROBLEM
  • IV. THE ENTROPY PROBLEM
  • V. THE NUCLEAR WASTE PROBLEM
  • VI. THE ACCIDENT RATE PROBLEM
  • VII. THE PROLIFERATION PROBLEM
  • VIII. THE ENERGY OF EXTRACTION PROBLEM
  • IX. THE URANIUM RESOURCE PROBLEM
  • X. THE SEAWATER EXTRACTION PROBLEM
  • XI. FAST BREEDER REACTORS
  • XII. FUSION REACTORS
  • XIII. THE MATERIALS RESOURCE PROBLEM
  • XIV. THE ELEMENTAL DIVERSITY PROBLEM
  • XV. NUCLEAR POWER AND CLIMATE CHANGE

This review of Abbot's article does not (as yet, if ever) attempt to discuss all these aspects, but some points to note are:

The Nuclear Site Location Problem

Abbot asserts that "One has to find locations away from dense population zones, natural disaster zones, and near to a massive body of coolant water."

In his first criterion Abbot doesn't specify how far away he thinks nuclear power stations should be from population zones, or what density of zones he thinks should be avoided.

Abbot's second criterion is that locations must be away from natural disaster zones. He doesn't give examples of such zones. Areas at risk of inundation by lava flows from active volcanoes are indeed probably best avoided. However Japan experiences some of the most severe earthquakes in the world and has 54 nuclear reactors, all of which survived, undamaged, the Great East Japan (Tōhoku) earthquake of 2011 which was the 4th most violent earthquake ever recorded anywhere. The reactors included designs dating from the 1960s and 1970s. (The only reason some of the reactors at Fukushima Daiichi were damaged was because the owners, TEPCO, had negligently failed to design for the magnitude of the tsunami encountered.) Nuclear power plants have also not only survived, but continued providing power through hurricanes such as Harvey and Florence in the USA.

The requirement for proximity to "a massive body of coolant water" is puzzling. As Abbot himself points out nuclear power plants can, and frequently do, employ air cooling, as do other thermal power plants sporting distinctive cooling towers. Abbot's preferred solar thermal generators are subject to the same laws of thermodynamics as nuclear and other thermal generators, and he proposes locating them in deserts where they will have to be air cooled, so the increase in cost Abbot assigns to air-cooled nuclear applies equally to them. As for the requirement for cooling water in emergencies, many nuclear power reactors are now designed to safely shut down and dissipate afterglow heat without external cooling.

The Land Area Problem

Abbot cites the work of Mark Z. Jacobson who claims that nuclear power plants require as much as 20.5 km2 of land area including not just the footprint area of the power station itself, but also its exclusion zone, associated enrichment plant, ore processing, and supporting infrastructure. He concedes that this is less than the area of a desert-based solar system, but claims that CSP takes up only "unused desert area, whereas nuclear stations tend to take up prime area adjacent to sources of coolant water". However deserts can be ecologically fragile and biodiverse environments which vast arrays of mirrors and generating equipment, and corresponding human activity, can disrupt or destroy.

Also, as noted above, nuclear power plants do not have to be sited adjacent to sources of cooling water.

Furthermore not all of the land area assigned to nuclear power plants has to be, or even can be, co-located: Uranium mines may be on the other side of the world from the stations they supply.

Jacobson's estimate is larger than the largest figure calculated by Vaclav Smil for 1 GW of nuclear reactor power. Smil's figures range from 0.61 to 13.6 km2.

The Embrittlement Problem

Abbot claims that neutron embrittlement of metal surfaces will require reactors to be limited to 40-60 years lifetime, leading to a requirement that one nuclear power station will need to be built and another decommissioned every day. However alternative technologies also have limited lifetimes. The biggest CSP plant to date is Noor in Morocco which has just over half the output of Abbot's notional 1 GW nuclear power stations, but at a far lower capacity factor - possibly 1/3 for ideal locations, or less. Assuming a Noor-type CSP plant has a similar lifetime to a nuclear plant we would have to be building and decommissioning 3 of these every day. Phase I of Noor has half a million mirrors.

The Entropy Problem

Abbot states that "In the same way that any electrical device or machine heats up and eventually fails, the same is inexorably true for a nuclear station." Why this is supposed to be a limitation for nuclear power stations and not other machines which heat up (and/or are subject to other stresses) and fail, such as concentrating solar power stations with millions of independently steered mirrors operating under hot and dusty desert conditions, Abbot does not make clear.