Does anyone know what the power consumption of what one of these chair massager things is? It's not a whole chair - it's just a seat and back that you rest on an ordinary chair & it massages your back and has an optional heater for when the weather gets cold. My old ma won't use it because she's afraid it'll use a lot of power & is cutting her electricity usage. I tried to explain it would only cost a few pence an hour (I'm guessing!), but I need to find a way to prove it to her. (She won't accept my offer to pay any increase in her electricity bill either).