Looking at p13 of the Annual Results for 2017 presentation, it does appear as though Contact are able to price themselves into an electricity market sweet spot.
https://www.nzx.com/files/attachments/263317.pdf
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1/"Contact’s hydro inflows typically peak during summer."
2/"Traditionally, wholesale and futures prices are lowest between October and February."
3/"Contact seeks to maximise the value of its renewable assets
by selling all renewable generation at a fixed price."
4/ "Flexible thermal generation, limited hydro storage, gas storage and hedges allows us to “firm” the renewable variability"
"Over the past 3 years this has enabled fixed priced sales at 125% of mean renewable generation,
in contrast to integrated renewable generation only peers who sell between 70-85%"
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