When you build a transformer, the default setting is 200kW. I feel a setting of 0kW would make more sense, so that you can set the needed power amount later. At the moment, I set a blueprint for a transformer in an isolated power net, forget about it for a while, then all my batteries in other nets start draining because the transformer got built and is sucking ungodly amounts of power.

Alternatively, could we have the option to change the default power setting?