Northland households will pay about $20 more a year from April as line companies increase their charges.

Far North will again see the highest rise as Top Energy hikes its line charge by 7 per cent, which will result in each household paying about 2 per cent overall or $20 more a year. It follows an increase last year of between $35 and $40 for Mercury and Genesis customers in the Far North.

An analysis of the cost of the cheapest electricity supplier change between February 2011 and February 2014 showed residential charges in the Far North had risen by $457, compared with the national average of $243.70.

Line company Northpower will increase its distribution price by 2.5 per cent from April and major power companies Meridian, Mercury and Genesis have signalled an annual hike in their prices of just under $20 for customers in Whangarei and Kaipara.


Contact, Trustpower and Nova are not raising their prices in Northland this year.

Top Energy chief executive Russell Shaw said in the past two years his company had raised its charges by 3 per cent although the Commerce Commission has allowed an increase of up to 7 per cent every year.

"We spend $15 million annually replacing our assets which is the highest percentage of our capital expenditure. Forty-three per cent of our customers are uneconomic to serve which is the highest in the country," he said.

Northpower spokesman Steve MacMillan said increases to distribution pricing were a reality of the costs involved in maintaining and upgrading critical infrastructure like an electri-city lines network to ensure ongoing reliability of power supply.

He said the company had an obligation to keep staff safe and a responsibility to public safety hence a continued need to maintain its electricity assets to a high standard.

Based on an average annual consumption of 7858kwh per year for a medium-sized household, Nova is currently the cheapest provider in Whangarei at $1981, followed by Energy Online at $2078. Trustpower is the most expensive provider at $2364. In the Far North, Globug is the cheapest primarily because more Northlanders, particularly low-income earners, are signing up to the pre-pay electricity plan.