Meridian Energy's (ASX:MEZ, NZE:MEL) retail sales volumes rose to 913 gigawatt hours (GWh) in August from 810 GWh a year earlier, according to a Thursday filing with the New Zealand bourse.

Compared with last year, residential sales soared past 35%, large businesses rose almost 15%, small and medium businesses increased 7.2%, and corporate sales and agriculture were up 4.3% and 2.2%, respectively.

National electricity demand in August rose 5.9% from last year.

In the month to Sept. 8, national hydro storage decreased to 79% from 87% of the historical average, per the filing. Total inflows for August reached 73% of the historical average.