I would like to to add wind/solar power to my house. Will I have to rewire the existing wires or can I use the existing wires. The house is only 20 years old and is total electric.
Typically wind/solar uses an inverter to convert the DC back to 120/240 AC so the simple answer is that you don't do anything to your interior wiring.
Are you going to go the battery / inverter route ? Either way , have you considered how you are going heat water , cook , dry clothes , etc ? If you are all electric , you have a lot of things to consider . What part of the country do you live in ?