How Green is Solar Energy?
New Zealand is in the privileged position where around 85% of our electricity is generated from renewable sources such as hydro, wind and geothermal. This is different to many other developed countries, which rely heavily on fossil fuels or nuclear energy for electricity generation.
How do New Zealand's energy sources compare?
So, how badly does New Zealand need to invest in renewable energy, compared to other countries? Nearly 85% of our country's energy needs are being supplied from hydro, geothermal and wind generation, and we are ranked second in the world for renewable generation (as a percentage of total generation). This is forecast to increase due to fossil fuel generation reducing. Known geothermal and wind generation resources are the lowest cost renewable options, which will also cater for future growth in national demand.
Does New Zealand offer solar incentives?
For countries heavily reliant on fossil fuels for energy, there is a much greater need to find ‘green’, renewable sources of energy (such as solar), to reduce their country’s carbon footprint and reliance on non-renewable generation. For those countries, the economic analysis is quite different, and consumers are encouraged to invest in solar generation through incentives such as premium buy back rates for surplus generation exported to the grid. In New Zealand, there is no need to incentivise people away from fossil fuel generation to more renewable sources.
What are the impacts of solar equipment on the environment?
Although solar generation is renewable, there are wider environmental considerations associated with the panel manufacturing processes, and end-of-life disposal of solar panels.
Solar panel production requires electricity and, for example, while China is a leading global manufacturer of solar panels, around 77% of China’s electricity is generated from fossil fuels. This means that the manufacturing process contributes to greenhouse gas emissions.
The European Union's 'Waste Electrical and Electronic Equipment' protocols place responsibility on the solar industry to manage the recycling and disposal of solar panels. This is a future issue that will need to be addressed in New Zealand as some panels contain hazardous materials such as cadmium that could leach into the environment if disposed in a landfill.
Also to be considered is the environmental impact of the batteries required to operate a storage system.
University of Canterbury research has so far shown that batteries are not ‘carbon neutral’, in that the production and transport of the systems to New Zealand has a greater carbon output than is offset by their use in a country where the majority of electricity is generated from renewable sources. Their research also found that lithium-ion batteries had a short lifespan of around 15 years, and this would need to substantially increase to reduce their carbon footprint, especially considering the disposal issues around lithium-ion batteries.