Can Powers be used for Suppressive Fire? For example, can you cast a Bolt Power to do Suppressive Fire on an area?
The question in the title is a little different than the question in the body. As a result, I'll answer both.
Can powers do Suppressive Fire?
Sure, if the description of that power allows it.
Can the Bolt Power do Suppressive Fire?
No, not as written in the core rules. A GM would probably be more than willing to work with a PC who wanted to create a version of Bolt that did that, but the core power does not.
If a player wanted to use bolt for suppressive fire then I would probably do it as a trapping. As it makes the power a lot more powerful, it would probably be necessary to introduce some kind of down side to it (can't think of one off hand atm).