The Royal Navy Operates 6 Trafalgar class submarines and 1 Astute class. These submarines are called 'attack' or 'hunter-killer' submarines and have roles such as land attack using Tomahawk cruise missiles and anti-surface and anti-submarine roles using the Spearfish torpedo. They can also carry out surveillance and reconnaissanse.
The Royal Navy also has 4 Vanguard class submarines. These submarines are ballistic missile submarines. These submarines are responsible for the UK's nuclear detterent and use the Trident missile system. There is always at least one of these boats at sea at any given time.
The PLA navy has more than 225,000 personnel and is thought to have as many as 70 submarines, 10 of them nuclear-powered
230
170
nearly 155
Reactors power submarines and many surface ships. Nuclear weapons.
From Wikipedia: Today, six countries deploy some form of nuclear-powered strategic submarines: the United States, Russia, France, the United Kingdom, People's Republic of China, and India Several other countries, including Argentina and Brazil, have ongoing projects in different phases to build nuclear-powered submarines.
Most submarines now have a single nuclear reactor. Some smaller, coastal submarines have a single diesel.
Nuclear power plants are very large fixed installations on land. There are many reactors however in the US navy ships and submarines
Submarines are still used by many navies to watch other navies ships and to protect coastlines secretly.
At times it sure seemed like a lot more than there actually were, but counting U.S. NATO, and Soviet submarines, around 300. That includes both attack and missile submarines, DE and Nuclear.
As of end of 2010, the Russian Navy included 12 strategic submarines of four different types. The submarines can carry 160 sea-launched ballistic missiles (SLBMs) that can carry 576 nuclear warheads.
Libya has 100 aircraft carrier, 300 destroyer and 50 nuclear powered submarines..