Greenpeace's use of the word "tax" to describe an increased Unison Networks charge for solar power generators has been upheld by the Advertising Standards Authority (ASA).
In April, Hawke's Bay lines company Unison announced an increased charge for any household generating its own electricity that was also connected to the electricity network.
Unison said it was unfair the generators paid little on lines charges because they used little electricity yet were typically high users of electricity when there was peak demand during cold winter evenings. It said the peak demand kept lifting and all consumers should share the cost.
Greenpeace New Zealand labelled the move a "tax" designed to discourage people from installing solar panels on their roofs and released a Facebook page and a YouTube video.
The Facebook page was headed "Petition: Stop the Solar Tax".
The video showed a group of people singing and dancing following musician Tiki Taane to the office of the Electricity Authority, to deliver the petition.
Complainant L Chandler said Greenpeace's use of the word tax was misleading because the Unison charge did not fit the legal definition of tax - a levy imposed on a taxpayer by the state - instead seeking to "fairly spread the cost of the network upkeep across all consumers who are dependant on using the grid for the source of the power".
"As Unison is not only a private company, but adjusting from a User Pays to a Flat Fee, this is not a tax, and calling is so is playing on the public's fear perception that it is a tax."
The ASA ruled while Unison's solar charge increase did not fit the legal definition of the word tax it could be considered appropriate because the charges were compulsory.
It said the term was used to create an unfavourable impression of the network charges.
"This did not mean however, that the advertisement met the threshold required to be described as misleading."
Because the identity and the position of Greenpeace were clear the advertisement should be reviewed in the context of advocacy advertising - advertising designed to express an opinion - there was no apparent breach of the Advertising Codes and no grounds for the complaint to proceed.
Greenpeace's video has been viewed 42,000 times.
Unison is owned by Napier and Hastings electricity account holders and owns the electricity lines in Napier, Hastings, Taupo and Rotorua.
Last month it started sending $150 dividend cheques to electricity account holders.