Home batteries are a great idea, and may indeed pay for themselves in some climates and energy grids, but they are a Trojan horse. Smart homes give big corporations and big government access to your home energy consumption and the ability to dictate what you can and cannot use in your house.

In the U.S. (Maryland) the energy company asked to put a Smart Meter on my air conditioning unit. The idea was they would lower my bill in exchange during peek usage for a few weeks in the summer they would decrease the energy usage of my air conditioner. This was a lie. Normally my air conditioner would keep the house a cool 72 degrees (22 degrees Celsius) no matter what the temperature was outside. With the Smart Meter the air conditioner would only start up if it got over 92 degrees (33 degrees Celsius) inside the house. This meant all summer long the house was hot. It effectively kept the air conditioner off except in absolute heat waves. The energy company controlled my thermostat.

Big corporations and government are trying to get your data. Once this is achieved they will regulate your thermostat and energy usage. This may be inevitable, but we should at least resist when we can.