Wednesday, August 5, 2015

South Australia Nuclear Prospects Q5-8

Subtitle: Nuclear Power For South Australia Not Justifiable

This is part 2 of my responses to the 17 questions.   South Australia's Royal Commission on the Nuclear Fuel Cycle requested written responses to 17 questions on the topic of nuclear power reactors.  see link The reactors are but one of four topic areas, with the others being 1) uranium mining, 2) uranium enrichment into civilian power fuel, and 3) nuclear waste management and storage.  I was unable to submit answers to the questions for formal consideration by the Royal Commission, however, the answers are below for the second 4 questions.  Answers to the remaining questions will appear in separate posts.   The conclusion is that a nuclear power plant cannot be justified.  A small nuclear reactor would be required, which suffers from reverse economy of scale and is, therefore, very expensive for the amount of power produced.   The usual safety concerns also apply: operating upsets and radiation releases, population evacuation plans, spent fuel storage or reprocessing, and sabotage and terrorist attacks, to name a few.

The Commission's Questions and Responses  (5-8)

3.5  What are the conditions that would be necessary for new nuclear generation capacity to be viable in the NEM? Would there be a need, for example, for new infrastructure such as transmission lines to be constructed, or changes to how the generator is scheduled or paid? How do those conditions differ between the NEM and an off-grid setting, and why? 

New nuclear generation capacity in the NEM would be no more than 300 MW and preferably 200 MW to avoid unnecessary idling of load-following generating capacity.  Such small nuclear reactors are not economically favored.   The small minimum load of 700 to 800 MW at night is very small for a power grid.  Grid operation stability normally requires that no single generator exceed approximately 40 percent of the load.  If that single generator trips off line, additional generating resources must be brought on line rapidly to avoid grid failure.  

The NEM setting would also require a nuclear plant to be located where a radiation release to the atmosphere would be blown away from populated areas by prevailing winds.  

An off-grid setting would be specific to the demands of the off-grid load, including load-following.  Also, with no grid to provide power during unplanned shutdowns and shutdowns for maintenance, the off-grid load likely will require a shutdown whenever the nuclear plant is stopped for breakdowns, maintenance, refueling, severe natural events, security threats, or safety violations.  

3.6  What are the specific models and case studies that demonstrate the best practice for the establishment and operation of new facilities for the generation of electricity from nuclear fuels? What are the less successful examples? Where have they been implemented in practice? What relevant lessons can be drawn from them if such facilities were established in South Australia? 

There are, at present (2015) approximately 438 operating nuclear power plants globally, with another 60 under construction.  Very few new nuclear plants have been started up recently.   The usual model for a nuclear plant is the government assumes almost the entire liability for a radiation release, and subsidizes the plant construction costs.   As noted in the US’ Price-Anderson Act, which provides for the government assumption of liability, no nuclear plants would be built absent the government assuming the liability.  Insurers would require far too much money in the form of insurance premiums for nuclear-based power to be cost-effective. 

Additional forms of nuclear power subsidy include:
1) huge construction loan guarantees from government, approximately $8.3 billion for the US’ Vogtle plant construction alone,
2) regulation that no lawsuits during construction will be allowed (with a minor exception),
3) a carbon tax on fossil-fuel based electric power generating plants, 
4) regulation to raise electricity prices during construction to avoid interest costs on construction loans,
5) operating regulations that are routinely relaxed to allow plants to avoid spending money to comply,
6) direct subsidy of typically 1.5 cents (US) per kWh sold for the first decade of a nuclear plant’s operation,
7) a large guaranteed power price that is far above competitors’ pricing, as at UK’s Hinkley Point C proposed plant.

The best practice at this time appears to be the EPR reactor system under construction at two locations, Flamanville in France and Olkiluoto in Finland.  Both reactors are large to attempt to capture economy of scale, at 1600 MWe output.  Both projects failed to meet target schedules by several years.  Both projects also failed to meet target budgets by billions of Euros.  The Finland project is involved in legal claims between the various stakeholders.  

Four new reactors are under construction in the US, two each at Vogtle in Georgia, and Sumner in South Carolina, with all four having the Westinghouse AP-1000 PWR reactors at 1,200 MWe output.  All four reactors are years behind schedule and substantially over budget.

There are claims that nuclear plants being built in China are much less costly and are completed in four years.  The lower costs may be attributed to the very low wages for labor.  
If nuclear plants are built in Australia, construction costs can be expected to be more in line with the US and Europe rather than the China experience.  With the small size required for the NEM, costs will be much greater as economy of scale will not exist for a 250 to 300 MW reactor.  

Less successful examples include the Three Mile Island reactor and its partial meltdown.  The Rancho Seco nuclear plant in California, USA was shut down after repeated radiation releases and safety issues.  

3.7  What place is there in the generation market, if any, for electricity generated from nuclear fuels to play in the medium or long term? Why? What is the basis for that prediction including the relevant demand scenarios?

There is no place for electricity that is generated from nuclear fuels in the medium term, or long term.  As stated above, a nuclear plant in South Australia would be small, and suffer from high capital cost due to economy of scale.  Electricity from such a small reactor would be, therefore, far more expensive even if fuel costs were small.  In the long term, electricity that is generated from renewable sources such as wind, solar, and ocean currents are expected to be far less expensive, more reliable, much safer, and have less environmental impact than nuclear-produced power.  It is noted that Australia has a tremendous ocean current off the East Coast, the East Australia Current.  In addition, for intermittent wind energy, grid-scale power storage or its functional equivalent is available with the MIT system of submerged hollow spheres offshore near the coast.

For a relevant demand scenario, it is advantageous to consider historic grid demand growth and extrapolate into the time period of interest.  Grid demand typically follows population growth, but must be adjusted for anticipated industry needs, cogeneration, and distributed generation.  It is noteworthy that mineral processing may be performed near the mine if low-cost electricity is available at the mine.  However, the mineral processing may also be performed at sites nearer the end-user where electricity costs at the mine are high and transportation costs are low. 

Given the above, a demand growth of only 2.5 percent per year results in demand more than triple in only 50 years, and approximately 10 times greater in only 94 years.  A three-fold increase in demand for South Australia would bring minimum demand to 2,100 MWe, which would still not support the 1,200 MWe nuclear plant that is presently considered the best available technology.  Considering time frames beyond 50 years is very likely too speculative.  

3.8 What issues should be considered in a comparative analysis of the advantages and disadvantages of the generation of electricity from nuclear fuels as opposed to other sources? What are the most important issues? Why? How should they be analysed?  

As noted above, substantial subsidies are required for any size nuclear reactor, else no reactor would be built.  Large size is required for economy of scale, but the grid must provide the load when the large nuclear plant is off-line for maintenance, refueling, breakdowns, emergencies, severe natural events, and security and safety violations.  Other considerations are radiation emissions, evacuation plans, spent fuel storage for a very long time, cost to decommission, and excessive water use in nuclear plants compared to other forms of generation. 

When a nuclear reactor is not generating, it is a substantial load on the grid to maintain core cooling.  Provision must be made to provide redundant and reliable grid power to the nuclear plant so that adequate cooling is maintained for the decay heat in the reactor and spent fuel pool.  

Other sources of power generation also should have their relative advantages and disadvantages quantified and compared.  The California Energy Commission's study, referenced in Q3.4 above, compared 21 technologies including various forms of coal, natural gas, hydroelectric, nuclear fission, and renewables.  The renewables included onshore and offshore wind but both without storage, solar PV and thermal, geothermal, biomass, and ocean waves.   It should be noted that the CEC study did not include grid-scale storage as described by MIT, which involves placing hollow spheres in moderately deep ocean water such that wind energy pumps seawater out of the spheres.  When power is required on the grid, seawater flows into the spheres through conventional hydroelectric turbine/generators.   Such grid-scale storage adds to the installed cost, but substantially increases the value of the intermittent power from wind, is load-following, and dispatchable.

Also from Q3.4 above, factors for installing any generating facility on a grid, including NEM, include infrastructure availability, capital cost, operating cost, safety, reliability, turn-down ratio, ramping rate, fuel availability, cooling requirements, transmission requirements, impact on the grid from planned and unplanned shutdowns, years required during construction before connecting to the grid, and environmental impacts from both ongoing operations and after the facility closes at the end of its useful life. 

The most important factors are safety, reliability, and unsubsidized-cost of power sold to obtain a modest return on investment.   Almost all of the other factors can be partially or entirely overcome with sufficient care in design and expenditure of capital, but that capital expenditure increases the final cost of power sold.    None of the non-nuclear alternatives pose the safety threat of serious radiation exposure, which places public safety at the top of the list of important factors.  

For the International Atomic Energy Agency's (IAEA) perspective on the safety considerations posed by a nuclear power plant on a grid, one should refer to "Safety of
Nuclear Power Plants: Design, No. SSR-2/1 Specific Safety Requirements (2012)" available online from  see link This is but one of 13 Safety Guides available from IAEA.   This Design document lists 82 specific design Requirements for nuclear power plants.   The conclusion to be drawn is that a nuclear power plant is a serious threat to public safety and must have expensive and elaborate design and operational safeguards.  Even with such design and operational safeguards, nuclear power plants have melted down with subsequent radiation exposure that impacts people and the environment (3 reactors melted down at Fukushima Dai-ichi, Japan). 

For the International Atomic Energy Agency's (IAEA) perspective on the reliability considerations posed by a nuclear power plant on a grid, one should refer to "Interfacing Nuclear Power Plants with the Electric Grid: the Need for Reliability amid Complexity," available online from  see link From page 7 of the IAEA Interfacing publication, 

"In addition to assuring that the electric grid will provide reliable off-site power to NPPs, (nuclear power plants), there are other important factors to consider when an NPP will be the first nuclear unit on the grid and, most likely, the largest unit. If an NPP is too large for a given grid, the operators of the NPP and the grid may face several problems. 

• Off-peak electricity demand might be too low for a large NPP to be operated in baseload mode, i.e. at constant full power.  (note, operating at other than full power requires a higher sales price for electricity - Sowell)

• There must be enough reserve generating capacity in the grid to ensure grid stability during the NPP’s planned outages for refuelling and maintenance.

• Any unexpected sudden disconnect of the NPP from an otherwise stable electric grid could trigger a severe imbalance between power generation and consumption causing a sudden reduction in grid frequency and voltage. This could even cascade into the collapse of the grid if additional power sources are not connected to the grid in time."

Questions 1-4 and answers, see link
Questions 5-8 and answers, this article
Questions 9-12 and answers, see link
Questions 13-17 and answers, see link

Roger E. Sowell, Esq.
Marina del Rey, California

copyright (c) 2015 by Roger Sowell

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