“We have only discovered a few vents so far because we have just started looking for them.”
The first one was discovered in 1977. We have been looking for them for over 31 years.
While I will agree that more will be found, why do you expect to find more geothermal hot spots at underwater plate boundaries, than occur along plate boundaries above water ?
“If supper hot seawater is pouring out of these vents it can only mean that the molten magma is just feet below not miles.”
Your assumption is invalid.
http://www.extremescience.com/deepcreat5.htm“A hydrothermal vent is a lot like an underwater geyser. Sea water seeps down into the cracks and fissures created by the spreading of the sea floor, sometimes as much as two or three miles into the earth’s crust.”
“So to say that we would be destroying all of them is a bit short sighted?”
You would be destroying all of the known ones with one or more small power plants. I don’t think you could get 55MW out of all of the known ones. That was the purpose of the questions, which you did not even attempt to answer.
“At current consumption rates this tells you how long it will take to consume all of it. This date will occur during your lifetime.”
Again, your assumption is invalid. You have no idea how long or short my expected lifetime is. And I don’t even want to guess at what your math might be.
While wind and solar (or geothermal) will never replace oil, they can all make a contribution to the energy problem. It is an energy problem, not just an “oil problem”.