Mercury NZ (ASX:MCY) forecast hydroelectricity generation to 3,400 gigawatt-hours for the full fiscal year due to continued dry weather in the Taupō catchment, as well as projected below mean water inflows and lake level in the fiscal third quarter, according to filings with the New Zealand and Australian bourses.

Hydroelectric generation in the fiscal third quarter reached 710GWh, 29% lower than the previous year, the filing said.

It said water inflows were the lowest on record during the quarter, resulting in high spot electricity prices averaging NZ$225 per megawatt-hour in Auckland. Forward prices in Auckland remain high at NZ$205 per megawatt-hour for the fiscal years 2025 to 2027, as of March 31.

Waikato catchment inflows were the lowest on record over the quarter which saw Q3 hydroelectricity generation fall to 710GWh 29% lower than the prior corresponding period.

Lower average wind speeds caused wind power generation to fall 28% quarter-over-quarter to 373Gwh. Geothermal generation was 35GWh lower than the same period in the previous year at 629GWh.

The firm revised its fiscal year earnings before interest, tax, depreciation, amortization, and fair value adjustments guidance to NZ$760 million from NZ$820 million.