Energy Savings

I asked my parents about saving our energy bill, my dad told me that it wont make much of a differnce because we have seven people in our house and he has just added more photovoltaic panels on top of our roof.  The bill that I brought to class was from september and since then he said that we have added one more set of panels to our roof.  My dad told me that our energy bill is arround eighty dollars.  I think that it isn't that bad considering my brother runs his ac all night, we have 4 refridgerators, and all of our rooms have ac.  In my house we also use solar water and propane fore our stoves and dryer.  My dad tries to consierve as much energy as he can because he says that the energy prices are just going to rise continuesly.