The sun is an abundant energy source that’s freely available and renewable.
How solar energy works
We harness the sun’s energy in several ways. Passive solar design is the use of solar radiation to heat our buildings. Buildings that are specifically passive solar designed make best use of the sun’s free warmth in winter, whilst keeping it out in summer when it is not needed. Solar panels, also known as photovoltaic (PV) panels, generate electricity directly from sunlight. Solar energy can also be concentrated to heat and store energy in material such as water. Another technology, solar water heating, uses the sun to heat water.
Pros and cons of solar energy
Solar energy systems in the form of passive housing, photovoltaics, and concentration are silent, unobtrusive, scalable, and can be used all around the country. These systems often have a high upfront cost, but once installed there is little ongoing cost.
The return available from an investment in a solar energy system is highly dependent on its application. Large scale wind, geothermal and hydro are renewable options that generate electricity much more cheaply than domestic solar panels. For solar water heating systems the higher upfront cost compared to other water heating systems means that it is not always cost-effective, particularly for households with low hot water usage.
The future of solar electricity
Solar generation is currently a small proportion of New Zealand’s energy supply, making up only 0.24% of our total renewable energy. Price reductions in solar PV equipment have made it more popular with homeowners and businesses, despite the fact that for most it remains more costly than grid-supplied electricity.
Solar PV is regarded as a ‘disruptive technology’ as it challenges the traditional model of electricity provision. Along with other disruptive technologies (such as advanced metering, smart devices, advanced batteries) it’s likely to contribute to changes in energy market design, energy policy and pricing structures in the future.