Russia Builds World's Largest Nuclear Powered Ice-Breaker 153
Hugh Pickens writes "Eve Conant reports that Russia's dream to dominate the Arctic will soon get a boost with a $1.1 billion nuclear-powered icebreaker 170 meters long and 34 meters wide. It's designed to navigate both shallow rivers and the freezing depths of the Northern Sea. Powered by two 'RITM-200' compact pressurized water reactors generating 60MWe, the world's largest 'universal' nuclear icebreaker is designed to blast through ice more than 4 meters thick and tow tankers of up to 70,000 tons displacement through Arctic ice fields. Why the effort and cost? 'Climate change is a pivotal factor in accelerating Russia's interest in icebreakers,' says Charles Ebinger. 'With climate change we are seeing a major change in the Northern Sea Route, which is a transport route along Russia's northern coast from Europe to Asia. Just in the last few years, with less and less permanent sea ice, maritime traffic across the Russian Arctic has risen exponentially.' The expectation is that the melt will continue, but there are still sections of route that would require icebreakers to keep it open year round. Icebreakers are an excellent example of a special purpose vehicle that is very poorly designed for operation outside its specific envelope. The key element is the rounded bow, a shape best suited to riding up on ice shelves and crushing them from above, causing the ships to roll from side to side in the waves when sailing on open water, making for a very seasick ride for the crew. Russia is the only country in the world currently building nuclear icebreakers, and has a fleet of about half a dozen in operation, along with a larger fleet of less powerful, diesel-powered icebreakers. The U.S. has been relying on a Russian diesel icebreaker to deliver supplies to Antarctica due to our own shrinking fleet of the cold-water, diesel-fueled vessels."
Re:War with Canada? (Score:5, Informative)
Russia (and USSR before it) has been building nuclear-powered ice breakers for 65 years now.
Re:A better way? (Score:5, Informative)
Russia is the only country in the world with a significant population on the Arctic-facing shores (Canada and Norway are distant runner ups), so it has a rather rich history of building icebreakers.
Re:Northern Sea? (Score:5, Informative)
Re:What's the point? (Score:5, Informative)
The point is that most of the time, the Arctic is still impassible without icebreakers, and oftentimes even with icebreakers. With global warming, more and more of the Arctic is traversable by ship for more and more of the year, and these massive icebreakers are going to give whoever owns them and a bunch of Arctic ports a leg up on shipping in the area.
Re:A better way? (Score:5, Informative)
1) The ambient temperature is below freezing. Seawater has a freezing temperature of about -2 C. The ice is fresh water - freezing forces out most of the impurities like salt (which is why people have suggested towing icebergs to lower latitudes as sources of fresh water). Consequently, any ice which gets melted would simply re-freeze solid again when it contacted the surrounding ocean water. It'd be like trying to cut your way through a metal floor over a meter thick using a blowtorch. The metal you manage to melt would simply flow and resolidify as it reached the bottom. Any advantage of ice being brittle is lost when you're introducing liquid water which will flow into and seal any cracks you manage to make the moment the crack reaches the ocean underneath.
2) Steam is uncontained. It flows and spreads out when it encounters resistance, thus decreasing the force at any point. The beauty of moving your ship on top of an ice sheet is that the weight of the ship is borne by the singular point of ice which is highest. That's what causes it to fracture even though the sheet as a whole may be able to support the weight of the ship. A similar strategy is used for the pilings of offshore oil rigs in areas which get iced over. If you try to build them to just resist the ice, they will be crushed and fail. Instead, they're designed with a curvature which lifts the ice. A flat ice sheet resting on a curved surface means all the weight of the ice is borne by a single point, easily causing it to fracture and move around the piling.
3) Water has a fairly high heat capacity and heat of vaporization (it takes a lot of energy to heat it up and to convert it to steam). The Russian nuclear-powered icebreakers I find on Google are listed as 21,000 tons with a draft of 9 meters (the bottom of the ship extends 9 meters below the waterline). So raising the front half of it above 1.5 meters of ice requires mgh = (21,000/2 tons)(9.8 m/s^2)(10.5 meters) = 9.8x10^8 joules of energy. Water has a heat capacity of 4.2 J/g*K and a heat of vaporization of 2260 J/g. So taking freezing ocean water and heating it to steam requires 420+2260 = 2680 J/g. 9.8x10^8 joules will let you convert only 367 liters of water to steam. Less if you want to raise it above 100C, and less if you want to pressurize it above 1 atmosphere. And I suspect the icebreakers are designed with a shallower draft at the bow, to ease lifting it above the ice.
Re:A better way? (Score:4, Informative)
"or run a heat exchanger with some anti-freeze" Got that covered for you.
My driveway will not sink into the cold north Atlantic if too much ice builds up on it, nor am I at risk of being swept out to sea when I shovel the snow off of it. Loss of craft and loss of life are both costs that you need to include in your analysis.
Unless they are constructed carefully, pipes embedded in concrete or asphalt can be broken when the concrete cracks or the asphalt shifts (this is a common failure mode, talk to anyone with an "Eichler" in Silicon Valley, also seen in heated driveways where I live). A ship that cracks has bigger problems. In addition, cleaning a driveway with heat includes the cost of the heat itself, where a ship has waste heat from its engines.
Sanity check -- waste heat exceeds power, so use power of engine to estimate heat available. 1kwH = 860kCal = 14 kg ice melted (60 cal/g heat of fusion). Artika class icebreakers [wikipedia.org] have reactors on board totalling 340MW (I think that is heat power, not engine power, so take half of that, 170MW), therefore enough waste heat to melt 2380 metric tons of ice per hour (roughly = 10% of the displacement of the boat, also 2380 cubic meters of ice. Cross section of ship below waterline is also vaguely in the ballpark of 238 square meters, so melting your way forward would only get you 10 meters/hour.). Perhaps, rather than routing the antifreeze through pipes, it would make sense to have a few centrally mounted hose connections for spraying (very) warm sea water where you wanted ice melted.