backtop


Print 50 comment(s) - last by Schugy.. on Dec 29 at 8:06 PM


An artist's depiction of a series of the new reactors in a future deployment.  (Source: Westinghouse)
Construction on new designs should begin within weeks; ultra-safe Gen. III+ reactors could be live by 2016

When it comes to alternative energy, wind and solar power are nice ideas and certainly worthy of research, but they remain much more expensive than nuclear power.  Nuclear power, however, has suffered mightily under the misconceptions of a poorly informed public that mistakenly believes that modern reactors designs are as failure and toxic waste prone as legacy designs.  

Protests and lawsuits have blocked the construction and licensing of clean modern reactors, and then to add insult to injury critics tend to turn around and throw these cost overruns they created back at nuclear proponents, complaining that nuclear power is prone to "cost overruns".

I. NRC Approves First Gen. III+ Reactor Design

Well the U.S. Nuclear Regulatory Commission is doing its best to restore some sanity to the power market, making one of its biggest moves in recent years, unanimously approving [PDF] a new reactor design and setting in a new faster, streamlined approval process.

The new design is the AP1000 by Westinghouse Electric Comp. LLC (a licensee of Westinghouse Licensing Corp., which in turn is loosely a subsidiary of CBS Corp. (CBS)).  The AP1000 is a 1,154 MW "advanced" third generation reactor design (often dubbed Gen. III+).

Reactor design
A peek at the new modular design, which features a dramatically reduced footprint. 
[Image Source: Westinghouse]

It originally won NRC approval back in 2006, but then in 2008 the NRC implemented a series of strict regulations [source] requiring that reactors be designed to sustain a direct strike from a commercial (i.e. large cargo or passenger) aircraft.  The initial design, which included a concrete enclosed containment vessel, was deemed unsatisfactory as it could crack under the impact.

Westinghouse went back to the drawing board, adding a steel plate enclosure, which they argued would counteract the collision and keep the reactor safe.

II. Westinghouse Battled to Overcome Criticism

The refined design was resubmitted, but suffered an arduous approval process, thanks to attacks from several different sources.  One criticism came from John Ma, a senior structural engineer at the NRC.  In 2010 he filed a claim, arguing that Westinghouse was wrong in their safety assessment of the plant's steel structure.  

A 2011 Scientific American report describes:

Last year Ma, a member of the NRC since it was formed in 1974, filed the first "non-concurrence" dissent of his career after the NRC granted the design approval. In it Ma argues that some parts of the steel skin are so brittle that the "impact energy" from a plane strike or storm driven projectile could shatter the wall. A team of engineering experts hired by Westinghouse disagreed...

Passenger jet
The approval process of the new design stalled on concerns of whether it could sustain a direct hit from a passenger/commercial jet hijacked by terrorists. [Image Source: Sukhoi]

The approval process was also slowed by a complaint from a coalition of environmental activists who argued [PDF] that the approval should be delayed indefinitely to assess the:

...ongoing catastrophic accident in Fukushima, Japan, and decides what “lessons learned” must be incorporated into the AP1000 design and operational procedures to ensure that they do not pose an undue risk to public health and safety or unacceptable environmental risks.

These environmentalists essentially admit that they have poorly researched the topic, writing:

It is apparent that while little is known definitively about the cause and impacts of what occurred at Fukushima, many aspects of the accident have grave consequences for U.S. nuclear plants, including the AP1000 reactors.

This, of course, is patently false.  Anyone who's been following the story and has marginal ability to comprehend and digest facts realizes that the Fukushima disaster showed that:
  1. Even a relatively poor legacy design can withstand the brunt of an earthquake unscathed.
  2. The disaster was caused by the loss of power that prevented the safeguards from shutting down the reactor, leading to a buildup in pressure that cracked the containment vessel.
  3. Lesson learned: any reactor in a region where there's a flood or tsunami risk should not only waterproof their backup generators, but should also contain backup modular cabling, in case the line is severed during a dual event (e.g. an earthquake+tsunami).
Furthermore, this complaint seems particularly silly given that the AP1000 is designed to be able to go through a powerless shut down, in the case of a power loss.

Fukushima workers
"Environmental" activists complained that the AP1000 could create the next generation Fukushima.  Apparently they didn't get the memo about its capability to passsively shut down. [Daisuke Tomita/AP]

The NRC, however, dismissed these criticisms, saying comprehensive testing showed the reactor to be safe.  Gregory B. Jaczko, chairman of the NRC, commented, "The design provides enhanced safety margins through use of simplified, inherent, passive or other innovative safety and security functions, and also has been assessed to ensure it could withstand damage from an aircraft impact without significant release of radioactive material."

III. The Cheapest Form of Alternative Energy Available?

The approval puts the U.S. on the fast track to catching up with China, who is already deploying four of the cheap, safe AP1000 reactors.  The first of those reactors is slotted to go online in 2013.  The government-owned Chinese National Nuclear Corp oversees the Chinese deployment.  

Chinese plant construction
China has a three year lead on the U.S. in constructing the affordable and safe new design. [Image Source: Westinghouse]

The Chinese deployment gives some insight into the promising economics of the AP1000.  China paid $8B USD to Westinghouse and The Shaw Group (SHAW) to build the four reactors, indicating an average cost of around $2B USD per reactor.  Given an average life of 60 years [source] and a power output of around 1000 MW, the plants could each generate around 525.95 billion kWh over their lifetime.

This works out to about $0.0038 USD/kWh.  Even factoring in the typical cost of operation (around $0.01 USD/kWh) and fuel (around $0.0035 USD/kWh) [source], the generated power should cost about $0.02 USD/kWh, making it likely cheaper than coal.  Even assuming the cost of the plant doubles due to overruns, that would still place it at $0.0265 USD/kWh -- still cheaper than coal power.

IV. The Issue of the Waste

Of course this simplistic analysis neglects the important cost of waste disposal.  But even so, modular nuclear is expected to be substantially cheaper than other alternative energy options.  For example, waste disposal would likely have to increase the cost of the plant by nearly a factor of ten for wind power in its very cheapest regions (around $0.0675 USD/kWh in regions where wind is plentiful) to hope to keep up.  While waste costs are the subject of controversy and debate, it seems unlikely they will be that extravagant.  Thus modular nuclear power is likely the cheapest viable form of alternative energy.

And that's not even considering the important tertiary benefits -- a nuclear power source has none of the availability issues surrounding the intermittent nature of wind and solar.

The low costs are owed to the reactor's modular design, which allows the reactor to be assembled piece-wise using mass-producible parts.  It take 300 modules to build a reactor and the construction time is a relatively precise 36 months.  Thus costs are far lower than the "custom-built" reactors of yore.

Modular construction
The modular design cuts down on both plant design time and costs.
[Image Source: Westinghouse]

It's important not to sugarcoat the topic of waste.  There is waste.  And it's still an important downside, financially in terms of requiring safe storage.  That said, the new design is substantially "cleaner" than legacy reactors.

Annually it produces around 141 m3 of low-level dry waste, which can be compacted [source; PDF] to about 30-40 m3.  This isn't that drastic an improvement over legacy designs, but the real improvement comes in the reductions to low level liquid waste.  A typical 1950s-1960s era CANDU reactor produces around 250 m3 of liquid waste [source; PDF], where as the AP1000 only produces 21.6 m3.  Both the wet and dry waste can be safe stored in tanks on site, with 95 percent of the radioactive material decaying within 100 years and almost complete decay within 500 years [source].

The high-level spent fuel waste is produced in a quantity of 1 and 1/3 spent fuel multi-purpose canister (MPC) per year, with 264 fuel rods per MPC.  The entire high-level waste MPC output weighs 64.4 tons, of which 19.6 tons is spent fuel [source; PDF].  That puts the AP1000 at about the average cost [source] in terms of spent fuel.

But given the low cost of construction, utilities could conveniently deploy rebreeding reactors or other waste-reduction alternatives alongside a fleet of AP1000s to reduce the storage costs and space requirements, all while producing extra power.

V. AP1000 is Vastly Safer Than Past Designs

Aside from its passive shutdown capable design -- capable of powerless shutdown -- the AP1000 is also safer in other ways, as well.

It uses:
  • 50% fewer safety-related valves
  • 35% fewer pumps
  • 80% less safety related piping
  • 85% less control cable
  • 45% less seismic building volume
Parts

Less parts means less points of failure.  The AP1000 accomplishes this reduction by relying more on forces such as gravity and natural heat convection.

The building's seismic footprint is also reduced by the compact, modular design.  The NRC uses a measure "core damage frequency" (CDF) per year.  You may recall in the wake of Fukushima, the stink raised by an anti-nuclear activist editor at MSNBC 
 regarding supposed dangers of earthquake, given the NRC's requirement of only a 1x10-4 CDF annual frequency (which means that 1 event would happen per one hundred plants, every one hundred years, on average).

Well such critics can sleep soundly as the AP1000 features an impressively low 5x10-7 rate.  That means even with 450 plants -- more than enough to fulfill the U.S.'s 446 GW power demands -- there'd only be one seismic damage event every 22,000+ years, on average.

VI. U.S. is Now Only Three Years Behind China

Perhaps the phenomenal safety is why the NRC decided to wave the traditional 30-day waiting period before making the approval official.  That means applications for new construction will begin to be stamped for approval within a week possibly, with the first stages of construction set soon after.

Another benefit of the modular AP1000 is that the approved design qualifies for both a construction and an operating license.  In the past, given the custom nature of designs, a power company would have to seek these two licenses separately, which cost time and money.

The new approach is designed to prevent cost overruns.  In the 1970s and 1980s, the slow licensing process creating some cost overruns so huge that reactors were abandoned half finished.

The U.S.'s first planned AP1000s will be a pair housed at Southern Company's pre-existing plant Augusta, Ga., and another two housed at the Summer plant of South Carolina Electric and Gas in Fairfield County, S.C.

Control room
The new nuclear reactors will create high-paying controller jobs for qualified individuals -- Homer Simpsons need not apply. [Image Source: Westinghouse]

The new reactors could be online as early as 2016 -- just three years after China's first AP1000s.

No new reactor has been constructed in the U.S. since 1996.

Westinghouse cheered the move saying that the construction would create about 3,000 high paying jobs at each site, along with a smaller number of permanent jobs for new plant operators and engineers.

Obama at nuclear plant
President Obama, shown here promoting nuclear energy in 2010 has gotten a bit shy about discussing his support for nuclear power, afraid it will hurt his reelection bid. 
[Image Source: Inhabitat]

Congress has offered $18.5B USD in loan guarantees for new nuclear.  And President Barack Obama has offered his vocal support for new nuclear construction, although he has kept quiet on the topic of late, afraid of offending his voting base, which contains a large radical anti-nuclear "environmentalist" base.

Source: NRC [PDF]



Comments     Threshold


This article is over a month old, voting and posting comments is disabled

Nuclear Myths
By Paxus Calta on 12/25/2011 7:02:01 AM , Rating: 1
Reprocessing does not eliminate radioactive waste problems, it actually worsens them. Reprocessing (as it currently exists in the world) increases the total volume of rad waste dramatically, while creating expensive fresh fuel.

While 3rd Gen costs keep rising in the west (France and Finland), which are the only reliable places to get cost estimates from for 3rd Gen, solar costs continue to decrease. And are increasingly competitive with nuclear without the myriad headaches from waste to decomissioning to proliferation which nuclear suffers from

http://www.nytimes.com/2010/07/27/business/global/...




"I'm an Internet expert too. It's all right to wire the industrial zone only, but there are many problems if other regions of the North are wired." -- North Korean Supreme Commander Kim Jong-il














botimage
Copyright 2014 DailyTech LLC. - RSS Feed | Advertise | About Us | Ethics | FAQ | Terms, Conditions & Privacy Information | Kristopher Kubicki