One of the ongoing problems of nuclear energy is that pressurized light water reactors, or PWRs, and boiling water reactors (BWRs) require copious amounts of water to remove excess heat from the steam system in order to condense the steam.
Photo: mbgrigby, Creative Commons, Flickr
This water, obtained from rivers, lakes and oceans, passes through a circulating system that pumps water from the environment through thousands of metal tubes in the power plant’s condenser, and is then returned to the source, often no more than five degrees warmer.
More often, however, plants employ cooling towers to reduce the temperature of the water to normal. This is necessary because environmental regulations forbid discharging water whose temperature exceeds that of the water supply.
These cooling towers – while effective – are massive, ominous-looking structures shaped like inverted funnels which generate clouds of non-radioactive steam that the general public views with alarm and disfavor. The appearance of these towers is, in fact, what may have turned the US public against nuclear power in the first place, since the Three Mile Island (TMI) incident of 1979 did not cause any injuries. The radioactive release was a cooling failure.
In the United States, where all nuclear power reactors are either PWRs or BWRs, many are located by bodies of water. Since lakes and rivers are not a common feature in many densely inhabited parts of the country like Arizona, Senator John McCain’s (R – AZ) vision of doubling nuclear capacity if he becomes president has a fatal flaw. Another flaw, hinted at above, is known as the NIMBY (not in my backyard) factor. No one wants to look out their window at a 500-foot tall inverted cone of cement spewing unknown substances.
The Russians have a solution. They are building floating PWRs using 90-percent enriched uranium-235 fuel to produce power. These reactors, KLT-40’s, were originally developed for use in Russian icebreakers and to power a merchant-class vessel, the Sevmorput. Now, aboard ocean-going vessels like the Lomonosov, these mini-power plants will deliver 35 megawatt-hours each of energy wherever they are needed, including isolated villages, desalination plants and offshore oil drilling.
The Lomonosov, scheduled for completion in 2010, is the first of seven plants the Russians have on the drawing board. The twin KLT-40 reactors on board can supply enough power to serve a city of 200,000 or desalinate up to about 313,000 cubic yards of seawater a day.
These floating power plants will run for 15 years before returning to Russia for refueling, and have a 40-year lifetime before they need to be decommissioned. Their singular advantage is their diminutive size – less material to create a catastrophe – and the fact that they are always surrounded by enormous amounts of water.
Some commentators, however, have expressed misgivings about the safety of the floating plants. Nils Boehmer, a Russian nuclear power industry expert, points out that such facilities have never been used before and present a whole range of unforeseen, and thus unimaginable, problems. Immediate problems Boehmer does anticipate include a lack of security infrastructure in the remote areas where the floating power plants will be operated, and an inability to maintain a full complement of nuclear engineers onboard.
Sergei Kiriyenko, head of the Russia’s Federal Atomic Energy Agency, (FAAE, formerly Minatom), differs, pointing to the Kursk nuclear submarine disaster in 2000. The Kursk was sunk and, when later raised, the reactor was unharmed and immediately put into action. In addition, getting a full crew of engineers to stay onboard a floating nuclear power plant requires the same reward/discipline structure currently employed on floating oil rigs; good food, hot showers, comfortable beds and guaranteed future unemployability when workers fail to show up or leave without permission.
No one has mentioned the potential environmental degradation of the oceans if these floating plants are stationed near spawning grounds or in migratory pathways, where the discharge of heated water is likely to alter or destroy regional ecologies and the aquatic denizens who depend on them. Still, if we must have nuclear power, I’d prefer these floating adaptations, not so much because they are out of sight and therefore out of mind, but because their location makes containing the inevitable accidents easier, at least from a coolant standpoint.
Disclosure: I don’t own stock in any nuclear energy enterprise.