Meridian proposes to alter lake to generate more electricity

Meridian Energy's proposal to lower Lake Pukaki to capture more inflow and generate more power in times of an energy crisis has gone to the public for comment.

The state-owned electricity generator wants to have the ability to lower the country's largest storage lake a further five metres from its present minimum level of 518 metres above sea level. The lake has a maximum depth of 70m.

It has lodged an application for a plan change with Environment Canterbury. A dry summer has meant that the lake's inflow levels are some of the lowest for more than 80 years.

National grid operator Transpower was on the brink of issuing its first warning notice about security of supply when rainfall over the last few weeks temporarily resolved the issue.

Meridian documents suggest that lowering the lake could generate an extra 550 gigawatt hours of power.

"The benefits include lower wholesale electricity price in the period of emergency ... generating from renewable resources lowers the need for distillate, gas or coal fired generation," it said.

It said it could disturb the local flora and fauna but the effects would be temporary at best. However, the report acknowledged the potential for increased erosion as a result of the proposal.

People can contact ECan to lodge a submission. The deadline is July 6.

The Timaru Herald