Mel - You can use a rotary or touch tone phone when the power is out. Both are powered by the phone company. The company supplies 48 VDC (can vary depending on how you are served) and they are backed up by both batteries and generator. If you have a phone that requires AC like a cordless phone, for example, then it will be out of service when the power dies. But you are on the right path. A simple phone will continue to work when you need it.