Paul Kenneth Rose and Jane Clare Rose have been found guilty in the Auckland High Court of fraud against electricity retailer and generator Mighty River Power Ltd.

The Serious Fraud Office (SFO) laid Crimes Act charges in August 2014 of obtaining by deception for alleged fraud against Mighty River Power relating to procurement for the company's Southdown power station.

Paul Rose has been found guilty of nine charges of obtaining by deception and not guilty of one charge of obtaining by deception. Jane Rose has been found guilty of nine charges of obtaining by deception.

The charges were under section 240 of the Crimes Act 1961.

The SFO says Paul Rose was employed as an Electrical Engineer at the Southdown power station. It says he set up companies in the name of Jane Rose (and that of a former partner) to conceal his interest in, and connection to, these companies. 

"He then used these companies to invoice Mighty River Power, first on his own, and later with the assistance of Jane Rose. Mighty River Power was not aware of Paul Rose's interest in these companies and he did not declare the conflict of interest. Payments of approximately $2.2 million were paid to the companies by Mighty River Power."

The SFO says Paul Rose's offending took place between March 2006 and December 2012 and Jane Rose was involved over a period of time between February 2010 and December 2012.

Paul Rose and Jane Rose will appear for sentencing on 28 April 2016.