Yes, achieving ultra deep vacuums is not qwestion of energy but rather purity of the process. Cannot find any more the article which stated the billions bars pressure to be comparable with absolute vacuum.
It seems we refer to the outer space as "the absolute vacuum." I read recently that the deepest vacuum man reached on the Earth is about 1000 molecules per cm3. To obtain this there was needed energy sufficient to reach a pressure of 400 billions Bars.
Why space ships do not burst like...
While Universe now continue to expand due to the last BB, there is growing vacuum in the midst of it which with time will reach such tremendous value that the expansion will be stopped and the reverse process will start ?