New Zealand is unlikely to meet the Government target of 90% of electricity generated from renewable sources by 2025, the Institute of Professional Engineers (Ipenz) and University of Otago energy studies programme director Bob Lloyd say.
In a briefing to journalists yesterday, Ipenz policy director Tim Davin said the target reaffirmed in the Government's draft energy strategy was not possible under current market conditions.
Even if it was assumed all projects under construction or consented were built, renewable sources were likely to contribute only about 68% of the country's electricity, Mr Davin said during the Science Media Centre briefing.
Only two scenarios might get New Zealand close to the 90% target (a level last achieved in 1981) and both involved tinkering with the Huntly power station, the "cornerstone" of the country's on-demand generation.
One scenario described by Mr Davin required the removal of 75% of Huntly's generation, to shed about 500MW from the grid.
The other required the closure of half its generation and two major gas plants.
It was unlikely the Government could orchestrate either option in the current electricity environment to meet a target inconsistent with the wholesale electricity market system, Mr Davin said.
Mr Davin and Dr Lloyd criticised the Government's draft energy and draft energy efficiency and conservation strategies, on which public submissions close today.
The energy strategy sticks to the former Labour government's target of 90% of energy production from renewable fuels by 2025 while placing a new accent on the exploration and development of fossil fuels.
Mr Davin said New Zealand was vulnerable for its dependency on wind and rain to generate electricity.
There was also the "immediate problem" of the Cook Strait cable not having the capacity to move enough electricity if hydro generation faltered.
That would remain a problem until 2014, when Transpower finished upgrading the cable, but would be a real issue if next year was a dry year, Mr Davin said.
After that, generators would have to build so-called "peaking plants" to generate additional electricity when demand outstripped supply.
However, it would be up to the market to deliver security.
The strategy had little to say about renewable options.
Both Ipenz and Dr Lloyd believed wave generation was more of an option than tidal generation, but that it would provide only a small proportion of New Zealand's electricity needs.
Dr Lloyd said the draft energy strategy focused on exploiting fossil fuels in a trade-off that would cost the environment and world climate stability dearly.
The energy strategy also risked damaging the country's "green" reputation, while encouraging developing nations to say "why bother about climate change".
"It sends the wrong messages to the likes of China. When they see a developed country focusing so strongly on fossil fuels, why should they limit their use of them?"
The new draft strategy made the old 90% from renewables objective an aspirational goal "subservient to security and reliability" while proposing using fossil fuels whose reserves had not been quantified.
The strategies were devoid of detail or action, and needed to include goals and indicators of success, and to work through the trade-offs between economic growth and environmental sustainability, Dr Lloyd said.
