Energy is not generated by a specific state but the difference between two states. You can generate electricity from water at 500 degrees if there isn't a colder place to send it and allow you extract the difference.
So long as there was somewhere colder to create a difference it is potentially possible.
Yes, very easily. heat the water at the top of a hill, then pour it down a long steeply sloped pipe, with a turbine at the bottom end, voila, electricity!!
Actually, this works whatever the temperature of the water, lol
M is mass C is the specific heat capacity of water and dt is the change in temperature.
So if the diference in temperature is about 50 degrees and you've got a tonne of water at that temperature (C is 4200 Joules per Kg per degree)
Then there's a total amount of energy of about 4MJ of energy in that tonne.
That's enough energy to run a 1 bar electric fire for a little over a minute assuming you can get all that energy out at 100% efficiency and convert it to electricity
So to summarise.. if you have something that can absorb or carry heat away ie. at a different temperature then yes you can The greater the temperature difference the greater the amount of elecrical energy that can be generated.