The majority state-owned generator wanted to overcome a security of hydro supply regime, which it believed was "not fit for purpose" and provided "no confidence" that contingent storage would be available when needed.
It was confident no environmental issues would arise from lower lake levels — such as dust bowls and exposed spawning areas.
Meridian Energy chief executive Neal Barclay made those statements during a presentation about the company’s interim results earlier this week.
During the results presentation, Mr Barclay spoke about the challenges the country and electricity market faced with recent weather events, which included a "record-setting drought, followed by a record-setting wet period, followed by another record-setting drought".
He believed there were more hydro resources physically available, but a combination of system rules and consent restrictions meant the market could not count on that additional hydro generation — even in extreme circumstances.
"While hydro still makes up 60% of the country’s electricity generation, only about 23% of that capacity can be stored, and Meridian’s own storage represents just 15 weeks of our average generation."
Loosening those restrictions was the lowest cost and best option to both secure storage and to try to keep electricity prices down, he said.
To get confidence around contingent storage, they would likely target and advocate for lower average lake levels.
That would lead to avoiding spilling water during high inflow events which would generate more electricity.
This would "reduce our country’s carbon emissions, and reduce the cost of electricity to all consumers".
Mr Barclay said the changes the company were seeking would not create an environmental issue because the contingent levels were still highly unlikely to be used.
"We have a security supply regime that we believe is not fit for purpose and does not give participants confidence that contingent storage will be available when it’s needed.
"Now we’re working on this with Transpower and the Electricity Authority and government officials, but the situation is yet to be resolved."
A company spokesman confirmed yesterday Meridian would be meeting with the Guardians of Lakes today and one of the agenda items was a request from the minister of energy for both Meridian and the Lakes Guardians to consider options for more flexible operating guidelines, as well as opportunities to increase generation.
Guardians of Lakes chairman Darryl Sycamore confirmed the meeting, saying they usually met twice a year to discuss matters in relation to the operation of the Manapouri and Monowai hydro scheme.
At this meeting, however, they would also introduce a new piece of work between the Guardians and Meridian which would identify opportunities for additional generation during low in-flow periods.
"This work relates to ensuring security of supply for energy users. A number of lake management options have been identified which extend beyond the gazetted guidelines and will be the main topic of discussion in this week’s meeting."
