Hydro-electric storage lake levels were consistently above average during December 2006, but declined against the seasonal average.
At the beginning of December 2006, hydro lake storage stood at a healthy 3524 Gigawatt hours (GWh) or 133% of average for the time of year. As the month progressed, below average inflows caused this to drop to 121% of average, despite capacity having risen slightly to 3552 GWh.
The dramatic spikes when inflows were well above average during November were rarely repeated during December. Inflows were below average for the time of year on 21 days, ranging between 59% and 96% of average. On only 10 days during December, inflows exceeded average levels.
Despite the disappointing inflows, overall storage levels remained consistently above average, and well above water storage levels recorded during December 2005 – a year that caused concern about energy shortages.
There were no north-to-south transfers of electricity via the Cook Strait cable during December.
[Compiled from data supplied by M-co.]