Locally, Energy Online customers saw the biggest hike in charges as the company increased its power prices by $165.
Company spokesman Richard Gordon said higher network prices had contributed to the price rise. It had also been two years since Energy Online had reviewed its prices in Wanganui, he said.
"In that time, there's been significant increases across the board in network charging and other costs."
Mr Gordon suggested a price review was not necessary last year as the company had very few customers in Wanganui.
According to the ministry, less than 1 per cent of Wanganui power consumers were Energy Online customers in the 12 months to November 15.
Wanganui's largest energy provider - Genesis Energy - increased prices by $102 for the period, affecting 52 per cent of power consumers in the area.
TrustPower customers experienced no change in prices, as the company chose not to increase charges.
Powershop chief executive Ari Sargent said that, where energy companies' prices had increased, this was mainly due to higher transmission prices and more expensive retail costs. He expected power prices to edge higher next year as costs associated with the national power grid update filtered through to consumers.
"On average, I think most people would expect to see relatively flat prices, maybe a slight increase," Mr Sargent said.
"You expect from an end user customer point of view that most households should pay similar to what they're paying this year.
"They shouldn't be expecting a large increase in most cases."
Households in the King Country were least affected by power hikes - average bills rose $28 in the past year.
Far North residents were slammed with the largest increases, with average power prices jumping $306. In November, 29,246 customers switched power companies in New Zealand, according to the Electricity Authority. Nearly 1700 were from the Manawatu-Wanganui region.
Mr Sargent said "timing" played a large role in price changes.
Power companies decided for themselves when to pass increases in lines charges on to their customers, he said.
"About 90 per cent of what a customer pays is fixed either through ... the wholesale energy costs or transmission and distribution charges."
Customer servicing costs, the profit margin set by power companies and GST made up the rest, Mr Sargent said.
Power bill increases (in dollars) in the 12 months to November 15
Wanganui (Powerco lines)
+102 Genesis Energy
+81 Contact Energy
+81 Empower
+59 Energy Direct NZ
+165 Energy Online
+19 Just Energy
+108 Mercury Energy
+51 Meridian Energy
+121 Powershop
+0 TrustPower
Regional increases:
+87 Wanganui average
+ 99 New Plymouth average
+111 Rotorua average
+107 Hawke's Bay average
+117 New Zealand average
Source: Ministry of Business, Innovation and Employment/Sputnik PR
