Power charges have recently been floated by politicians as a questionable way to charge electricity customers.
The Energy Market Inspectorate will now examine five of the country's electricity network companies that have introduced an impact fee to see if they comply with the Electricity Act.
The authority has stated that "There is uncertainty among both electricity network companies and their customers about how the fees may be designed."
The government recently lifted the requirement that all electricity grid companies must introduce power charges from the turn of the year.
The power fee is partly determined by how much electricity is consumed simultaneously on a few occasions.
