Dunedin's renewable energy use declines

Dunedin is lagging behind the rest of New Zealand in its use of renewable energy, and the situation is getting worse, a study has found.

The Dunedin Energy Study, a joint initiative involving the Dunedin City Council's Enterprise Dunedin and University of Otago's Centre for Sustainability, has reviewed energy use across the city for 2017-18.

It found total energy use was up 5% for the year, to 13.4 petajoules, and that diesel remained the single largest energy source used in the city, at 33%.

About 32% of Dunedin's total energy consumption came from renewable sources, which was 2% down on the previous year.

It also meant Dunedin was lagging behind the national average, which is 40% of all energy consumed coming from renewable sources.

The study also found 677.7 kilotonnes of CO2-equivalent greenhouse gas emissions were attributed to energy use in Dunedin, the vast bulk (78%) coming from liquid fossil fuels.

The use of diesel and petrol as an an energy source was up 8.8% over the year.

And while total energy consumption was up 5%, total CO2 emissions were up 6% for the year, "which means Dunedin's overall energy portfolio was more emissions intensive ... compared to the previous year".

"This is the result of an overall increase in fossil fuel consumption and a small decrease in renewables within the city."

The reliance on fossil fuels coming from outside the city also represented an "area of vulnerability" to the city, if prices increased, as happened during 2018, it said.

"Opportunities to reduce these risks should be considered."

There was some good news in the study, though, as it highlighted the growing popularity of electric vehicles in the city.

Dunedin now had the highest rate of EV ownership in New Zealand, at about 4.1 vehicles per thousand people, compared to a national average of 2.6 vehicles per thousand.

The study also pointed to opportunities for improvement in the city, beginning with the transport sector as the main energy user.

It suggested more work to encourage the uptake of electric vehicles, ride-sharing, public transport and "active" transport - such as cycling - to reduce emissions.

The city's forests also provided another opportunity, as they already offered more than enough wood fuel to encourage the conversion of existing boilers in the city to wood fuels.

There was even potential for the city to develop a wood pellet production facility, providing fuel for wood burners, which could supply Dunedin and the wider South Island, it suggested.

The report will be considered by councillors at a meeting of the council's economic development committee tomorrow.