"Like our bee, renewable electricity is natural and essential to the planet, promoting well-being and real sustainability for future generations."
Developing the logo cost in the low six figures and the entire rebrand across the company was in the low millions of dollars, said Whineray.
There were ''huge amounts'' of customer and stakeholder research.
The old logo dated back to Auckland Electric Power Board days and was not distinctive, said Whineray. There was also confusion between the Mighty River Power which has around 93,000 shareholders and Mercury brands.
Asked if there was a danger of associating bees and being stung with power bills, Whineray said this hadn't come up in market research.
''If you go and touch electricity like touching bees that's not going to do you any good either. But just like what a bee does for the world, electricity is remarkably important. Don't touch it but do use it.''