If your fence was on their easement, it may have been an impediment to their rights.

We won't know that until we see the easement documentation.

It is possible that they will not be required to compensate you at all. Some easement agreements might require the servient tenement (you) to bear the cost of removal of impediments and obstructions which you have placed or you own.

Not trying to disagree with you but only to point out that easement agreements can vary widely and they have to be read to be understood. Ask the utility to provide you with written confirmation of their easement, and ask them in writing.