Instead of untested wind farms on liners, why not just use nuclear power. It is well tested (think aircraft carriers). Furthermore, while such a reactor may need fuel and disposal services, the wind farms will likely also require spare parts so the self sustenance thing may come out to be even or even in the favor of nuclear. Furthermore, nuclear reactors have a significantly better space/watt ratio allowing for more space for crew and servers.

There are other factors. Wind is intermittent -- not good for servers which have to be active 24/7. To use it would require massive (bigger even than what is already there) batteries which themselves would entail a massive extra cost. Nuclear power also allows easy desalination of sea water which (I assume) would be required for cooling sensitive electronic equipment (expensive servers).

The red tape associated with such an idea would be pretty scary though.