State-owned electricity company Mighty River Power has announced a $159.6 million profit after tax – an increase of $48.7 million from the year to June 2008.

The figure was largely due to one-off budget boosts. Revenue was down slightly to $1.1 billion, from $1.2 billion last year.

The ebitdaf (earnings before interest, tax, depreciation and amortisation and financial instruments) was also up, by 46% to $445.4 million.

The 10 year-old company’s portfolio includes the Waikato hydro scheme (nine power stations along the Waikato River); geothermal plants within the Taupo and Bay of Plenty regions; the Southdown co-generation station, bioenergy production and a wind development programme.

Mighty River’s underlying earnings were $209.9 million, compared to $136.2 million in the previous year. It will pay an ordinary dividend of $79.8 million - 50% of net profit after tax.

The company will also pay a special dividend of $150 million, reflecting one-off cash benefits including budget savings from the Kawerau Geothermal Power Station, the sale of Marsden B and “significant earnings” from “unprecedented hydro generation” last winter.

Mighty River Power chair Carole Durbin said the profit reflected a boost from the new 100MW geothermal station, Kawerau Geothermal Power.

“The key element in the Company’s operations contributing to this year’s stand-out financial result was a significant increase in renewable generation, which was up by 1,500GWh – a 36 per cent increase on 2008.”

In the first quarter of the year to June 2009, the Waikato Hydro system had its highest-ever inflows in a 90-day period.

“These higher volumes also received significantly higher wholesale prices in the first quarter, driven by low South Island storage levels at that time.”

Mighty River’s retail arm, Mercury Energy, attracted around 30,000 new customers during the year.