Designer Nikolai Kirillov has patented a project for a large non-nuclear submarine with an auxiliary low-power nuclear power plant. The idea eliminates the key problem of classic diesel-electric submarines (DESs) — the need to surface to recharge batteries.
In a conventional DES, energy accumulators provide underwater operation for only a few days. After that, the boat is forced to go to periscope depth to start diesel generators and recharge the batteries.
In modern conditions, such tactics almost guarantee detection by unmanned aerial vehicles, radar, or thermal imagers of the enemy, which critically reduces stealth.
Kirillov proposed a hybrid energy scheme. The project involves the installation of a monoblock low-power nuclear power plant up to 1 MW in combination with a diesel-electric engine and batteries.
A nuclear reactor with low coolant pressure and an energy module on an organic Rankine cycle generate electricity in a submerged position without surfacing.
This gives the submarine significantly increased underwater autonomy, reduced diesel fuel consumption and tank volume, reduced surfacing time for recharging, and increased stealth in the combat patrol area.