But the concept of a nuclear reactor stationed in the Arctic Sea has drawn criticism from environmentalists. The Lomonosov platform was dubbed "Chernobyl on Ice" or "floating Chernobyl" by Greenpeace even before the public's revived interest in the 1986 catastrophe thanks in large part to the HBO TV series of the same name.

Rosatom, the state company in charge of Russia's nuclear projects, has been fighting against this nickname, saying such criticism is ill founded.

"It's totally not justified to compare these two projects. These are baseless claims, just the way the reactors themselves operate work is different," said Vladimir Iriminku, Lomonosov's chief engineer for environmental protection. "Of course, what happened in Chernobyl cannot happen again.... And as it's going to be stationed in the Arctic waters, it will be cooling down constantly, and there is no lack of cold water."

Russia's civilian nuclear industry also faced public questions following the Chernobyl catastrophe, which shaped concerns about "the peaceful atom" for decades to follow. Construction of dozens of nuclear plants stopped, affecting not only massive Chernobyl-scale projects but also slowing down the use of low-power reactors like the one in what would become the floating station (The Chernobyl plant produced up to 4,000 megawatts. Lomonosov has two reactors producing 35 megawatts each).

"These reactors were initially to be used within city limits, but unfortunately the Chernobyl incident hindered that," said Iriminku. "Our citizens, especially if they are not technically savvy, don't really understand the nuclear energy and that these stations are built differently, so it's almost impossible to explain that to them."

The explosion at Chernobyl directly caused around 31 deaths, but millions of people were exposed to dangerous radiation levels.

The final death toll as a result of long-term radiation exposure is much disputed. Although the UN predicted up to 9,000 related cancer deaths back in 2005, Greenpeace later estimated up to 200,000 fatalities, taking further health problems connected to the disaster into account.

Modern Russia hasn't seen anything close to Chernobyl though. Russia, a major oil and gas producer, also operates several nuclear power stations. The state atomic energy corporation Rosatom has long maintained that its industrial record is one of reliability and safety, and that its reactors have been modernized and upgraded.

But project engineers say they've learned the lessons of Fukushima.

"This rig can't be torn out of moorings, even with a 9-point tsunami, and we've even considered that if it does go inland, there is a backup system that can keep the reactor cooling for 24 hours without an electricity supply," said Dmitry Alekseenko, deputy director of the Lomonosov plant.

The last Russian nuclear project of a comparable scale was completed in 2007, when the "50 Years of Victory" nuclear-powered icebreaker finally sailed after sitting in the docks since 1989. Now, after more than 20 years of arguments, changes of contractors and economic crises, Russian engineers can finally take pride in launching the world's only nuclear floating rig.