Energy manipulators can affect to some degree or another some form of energy; some can focus it, others can increase its strength (or decrease it), some can absorb it and either use it for other things or redirect it, and so on.
Some forms of energy include but are not limited to: fire, heat, electricity, kinetic, nuclear, solar/light, sound waves, etc.
While some manipulators cannot create the energy they are manipulating, there are some who actually can. Those who can't, need to find an external source and sometimes rely on special technology to help create these energy forms. Those who can actually manifest the energy have a potential to be more dangerous than those who can't -- you can take away someone's energy-creating technology to disable them, but what do you do with those who create it internally?
Brianna is an example of an energy manipulator on XMR. While she cannot create the energy internally, she is capable of absorbing it, manipulating it and re-discharging it at a target. Currently, the only energy she is known to be able to manipulate is electricity.