I already had 4 Rosewill Lightning 1300s. On my two most recent rigs, I used hellae's recommended EVGA 1300W supernova Gold PSU. (IMHO, these are overkill, but likely quite efficient.)
Yes but with the EVGA you can power up only 3 cards no ? 2 Cable/GPU ?
One suggestion, why don't you try having a solar energy? You can save electricity bills..