Hawke's Bay people are increasingly turning to solar power although an environmental service manager says the advantages of the systems come with costs.
There were 425 solar connections in Hawke's Bay at the end of March, up on 249 at the same time last year and 95 the previous one.
Of this year's connections, 399 were residential, 11 commercial and 15 industrial.
Energy Efficiency and Conservation Authority communications manager Jane O'Loughlin said most people were installing photovoltaic (PV) panels these days which created electricity from sunlight, rather than installing solar water heating.
Environment Centre Hawke's Bay manager Sarah Grant said solar systems had several advantages.
Their fuel source was free and would always be there, they required little maintenance and they were becoming more efficient.
However, the upfront capital cost of a solar system was high, from thousands to tens of thousands of dollars, depending on the specifications of the system required for the property. The cost of solar power also depended on those specifications, said Ms Grant.
Conventional power prices were increasing every year, so each year solar became a bit more realistic and worth the investment, she said. Solar users needed to pay the daily lines charge if they remained grid-tied. They would save on lines charges by disconnecting from the grid but batteries would need replacement from time to time and that could be costly.
Ms Grant said solar made the most economic sense when there was no current electrical grid connection and putting one in would be costly.
Hawke's Bay was a particularly good place to use solar power, because it had high sunlight hours.
Ms Grant said there was a clear upward trend in the use of solar as more people wanted to become energy independent. She said it was not possible to directly compare the sustainability of solar to other forms of energy production.
Many factors contributed to the sustainability of various energy types. Hydroelectric dams create electricity from water, which was renewable, but they were built with a huge amount of concrete, which released large quantities of carbon dioxide in its manufacture.
Solar systems were continually being developed and were made from many different types of materials, all of which had their own impacts on the environment, said Ms Grant.
Last month this newspaper featured a story on a proposal to turn Te Awanga and Clifton into New Zealand's fist solar-power settlement. Director of Goldpower Solar Hawke's Bay, Sebastian Nilsson, said with Hawke's Bay Farmyard Zoo, the Haumoana Four Square and Clifton Cricket club installing solar panels "we are well on our way to becoming the eco-village".
Nationwide, there were 9506 solar connections at the end of March, up on 5756 at the same time in 2015 and 2709 the previous year.
According to the Energy Efficiency and Conservation Authority, the main barrier to the uptake of solar energy was the cost. Solar generation made up only 0.1 per cent of New Zealand's total renewable energy.
Price reductions in solar equipment had made it more popular with homeowners and businesses, despite it being - generally - more costly than grid-supplied electricity. A report by the Concept Consulting Group on the effect of solar panels on greenhouse gas emissions said solar photovoltaic uptake was expected to displace generation from existing fossil-fuelled stations and therefore reduce emissions, in the short term.
However, it would have a limited effect in the medium term as uptake would substitute for new low emission power stations such as wind and geothermal.
That differed from most other countries because most of New Zealand's electricity was from renewable sources and large-scale renewables represented the cheapest option for future electricity supply here.