That is the same as saying that the sum total of everything is a constant. One reason for that is that knowledge, the subject of this book, get a meaning through it. Arrangement and representation. With the potential energy enclosed in an artificial lake no electricity can be made. That can only be done with the kinetic energy of the water that flows through the turbines.
Electrical energy is also energy.
In some sense it is a higher form of energy, with which gold can be melted, plates can be welded, trains can be powered, light can be created, and messages can be communicated. Think of the information embedded in our genes. Blue eyes and black hair are expressions of that information. A little bit of a charmer uses those to find a partner. He mobilizes this information.