The Future of Nuclear Power
In 1933, a Hungarian-American physicist Leó Szilárd conceived the nuclear chain reaction and patented the idea of a nuclear reactor jointly with the American-Italian Enrico Fermi. It took 18 years for electricity to be first generated by a nuclear reactor at an experimental station near Arco, Idaho. The world’s first commercial reactor was the Calder Hall station in England and the first plant to generate electricity for a power grid was the Obninsk nuclear power plant in theSoviet Union in 1954.
During the last 60 years, nuclear energy became an important component in the energy mix used by mankind. It supplies about 5% of the total global energy consumption or about 13.5% of the electricity we use. In theUnited Statesnuclear energy is the source of about 8% of the total energy consumption or about 20% of the electricity used.
The nation most dependent on nuclear electricity isFrance(75%), followed byBelgiumandSlovakia(52%), whileChinais the least dependent on it (around 2%). To date the only nation that has decided to shut down all its nuclear power plants (by 2022) isGermany. That nation today obtains 28% of it’s electricity from nuclear reactors.
Globally, 435 nuclear power plants are in operation and 60 are under construction. In the United States 104 are in operation, one is under construction and 28 have been shut down. Globally, due to ageing, 138 nuclear power plants have been shut down, but because of the high cost of dismantling and decontamination of the sites, only about 17 been fully decommissioned. In theUSAthe decommissioning of 13 plants is in progress. In addition to serving power generation, there are 240 reactors serving research and 150 reactors supplying energy for nuclear submarines and other ships around the world.
Earlier nuclear plants were often located near populated areas and these early plants were designed for only 30 years of operation. The life expectation of newer plants is usually 40 years and today, the average age of all operating plants is 27 years. The age of 138 operating plans is between 30 and 40 years, while 24 are already over 40 years old.
As of 2008, the installed capacity of all the operating plants in the world amounted to 413 GW (119 GW in theUnited States), while their actual electricity production rate was about 300 GW (~ 100 GW in theUnited States).
To date, the global investment to build nuclear power plants amounted to about $3 trillion (approximately $0.75 trillion in theUnited States). The cost of their eventual decommissioning is expected to be about another trillion dollars. If we also consider the associated costs of building and operating the uranium mines and also the cost of the temporary and eventually the permanent nuclear waste storage facilities, the total investment in the global nuclear industry is estimated to be about $5-$6 trillion. For comparison purposes, the global GWP today is about $65 trillion (USAabout $16 trillion).
The history of the last 60 years shows that after the accidents at 3 Mile Island and Chernobil the building of new nuclear power plants slowed down and the percentage of global electricity consumption that is met by nuclear power dropped from about 18% in the early 1990s to 13.5% today. It seems that this trend will continue after Fukushima, because of the ageing of the operating plants, the risks associated with cyber and conventional terrorism, military attacks, earthquakes and other causes, plus because the permanent storage of nuclear waste is still unresolved. Yet another concern is the increase of radiation in our global environment – including the doubling of the concentration of nuclear radiation in the atmosphere.
While these concerns are all valid, it is also a fact that the use of nuclear power can not abruptly be terminated, but has to be phased out gradually. Fortunately, it is also a fact that the operation of nuclear power plants can now be made much safer. Yet, in many respects they are not! Let me give some examples:
The nuclear power generation process is a relatively simple one: First the heat from the fuel rods is transferred into high pressure water that carries it into a boiler where steam is generated. Next, the energy of the steam is converted into electricity, while the waste heat from the turbines is taken to cooling towers to be rejected into the atmosphere.
Keeping such a process safely in operation requires only three things. Two of these are self-evident: 1) The need to keep the fuel rods covered by water to protect them from overheating and 2) To maintain the integrity of the containment building to prevent radiation from escaping. The third requirement is not so obvious, yet it was a main contributor to the accidents at 3 Mile Island, Chernobil and alsoFukushima. Let me briefly review all three causes:
Keeping the fuel rods from overheating and melting is guaranteed so long as the flow of cooling water is uninterrupted. As the operation of the cooling water pumps requires energy, that must be made available even if it’s outside source fails. This means not only that properly sized diesel and battery backup systems must be provided and must be located at safe elevations, but also means that the steam which, even during an accident is still being generated, must not be wasted, but must be made useable to drive backup cooling water pumps.
The second requirement is that the containment buildings must withstand both external and internal impacts. External impacts can originate from earthquakes, terrorist or military attacks, while internal impacts can be caused by events as like hydrogen explosions. Such explosions must be prevented by filling the containment building with inert gas, so that there is no oxygen present to support an explosion. In addition, automatic pressure release must also be provided and be furnished with filters to protect from the release of radioactive particles into the atmosphere.
The third requirement to achieve safe operation is the most neglected today. It is the need to protect the power plant from human error. In an age, when we can safely operate a nuclear powered robot on Mars, it is inexcusable to see that the safety systems protecting nuclear power plants are not fully automated. We have seen that in the cases of 3 Mile Island, Chernobil and Fukushima, the windows of opportunity for safe shut-down were lost, because the decisions on what to do were left up to panicked operators and PR oriented managers and because of their hesitation the window of opportunity for corrective action was not utilized.
Therefore, it is time for full automation, it is time for using measurement devices that can be trusted, it is time to install “firewalls” to completely isolate the operating controls from potential cyber attacks and most importantly, it is essential to fully automate the safety systems, so that for example, when an earthquake is detected, flooding of the reactors is automatic and immediate, instead of time being wasted until the tsunami waves arrive.
I agree with the environmentalists, who argue that we can not continue to live with energy sources that are inherently dangerous, because of the radioactivity or global warming that they cause. I also agree with them that resources are wasted on “scraping the bottom of the fossil barrel” or on waging “oil wars”. On the other hand, I disagree, if they believe that just by voting out denier politicians, we can switch to a safe energy-economy overnight. No, we can not! The transition to a safe energy economy has to be gradual no matter who is in the White House. It will take a decade or even a generation until this new “Marshall Plan” is completed.
Therefore, it is in the interest of all to increase the safety of today’s energy industry by replacing manual controls with full automation during the coming transition period.
Béla Lipták PE
Safety and automation consultant