[AaronBurns]

You could save money on your electricity bill with back-up/take over rechargeable batteries in every appliance or plug in device.
You could have back-up batteries for the whole house when you consider that they could come in different sizes and levels of power. This would be great in Black Outs.
They would charge in the appliance or device with standard power then seemlessly take over much like a Hybrid Car works.

Reward: Credit

[Steve]

As far as I know you always lose power by transferring electricity from one medium to the other (like charging batteries). So how could you save money in the process?