This part of the electric energy comes from the kinetic energy of the satellite, so the satellite needs a power source to move like this. That's exactly what happened. In fact, there is still thin air in the space where the satellite runs, so there is still resistance to the satellite movement. In general, solar panels are used on satellites to gain kinetic energy. After the satellite is scrapped, its orbit will gradually become lower, and finally it will land in the atmosphere and burn. China launched the Sino satellite (like Chang 'e-3) once had such a thing, the solar panels could not be unfolded, and hundreds of millions of RMB things became space junk as soon as they were launched. You can check it online.