Choosing energy options
If you want to generate renewable energy for your home, farm, or business, the first thing to assess is the wind, sun and water resources available - and how they might be harnessed.
On this page:
Reducing your electricity requirements
Photovoltaics (solar electricity)
Reducing your electricity requirements first
Whether you are building a stand alone power system (SAPS) or grid-connected system, the first thing to do is make sure your home or business is energy efficient.
If you are designing a SAPS, this minimises the amount of electricity you need to generate. With a grid-connected system, if you use less electricity onsite than you generate, this can be exported back into the grid.
Deciding which renewable energy options are best for you
A micro-generation system should be tailored to your situation and energy requirements. It's important from the outset to consult an expert for advice on the various system options, design and installation. Suppliers and installers of systems will be able to help assess which options are best for you.
When you're deciding which generating technologies are right for you, consider the availability of a suitable stream or river for micro-hydro, the average sunshine hours in your area, and how windy the site is.
A stand-alone power system (SAPS) is likely to utilise a number of different generating technologies in the same system. For example, these might include solar photovoltaics (solar panels that convert sunlight to electricity) and a small wind turbine, depending on available resources.
The most common stand-alone power technologies are:
- Photovoltaics (PV)
- Micro-hydro systems
- Micro wind turbines.
You'll also need to think about using batteries or an alternative source of power to back up your SAPS.
Photovoltaics
Photovoltaic (or PV) panels are often used to generate electricity in both stand-alone and grid-connected power systems. The main advantages of PV panels are that they are virtually maintenance free and fairly unobtrusive. Find out more about photovoltaics.
Micro-hydro
If you have a suitable stream, river, or reservoir, micro-hydro can be the cheapest micro-generation option. The advantage of a micro-hydro system is that it can provide a very consistent and reliable source of electricity compared to other micro-generation technologies. Find out more about micro-hydro.
Small wind turbines
A small wind turbine can also be considered if there is adequate wind onsite. Wind turbines are mainly used in rural areas. Generally, a minimum average wind speed of over 4.5 metres per second is required. No power is generated when there is little or no wind or, for some turbines, when the wind is too strong. In low-wind areas it may be better to invest in solar PV than a small wind turbine. Find out more about small wind turbines.
More information
- Efficiency first - by reducing your energy requirements, you'll reduce the amount (and cost) of generation you'll need.
- Stand alone power systems (SAPS) are off-grid electricity generation systems that may include photovoltaics, micro wind turbines or micro hydro, batteries and a back-up generator
- Grid-connected systems are electricity generation systems that may include photovoltaics, micro wind turbines or micro hydro. They are connected to the local electricity network, and can export excess electricity, or use mains electricity as a backup
- Solar PV or photovoltaics convert the sun's rays to electricity.
- Micro hydro for households is typically less than 5 kW
- Micro wind energy refers to the use of small wind turbines typically less than 10 kW
- Micro-generation is one form of distributed generation, which refers to local electricity generation connected to lines networks, rather than the natioal grid.
- More about use New Zealand's use of renewable energy.
- Sustainable Electricity Association of New Zealand
- Electricity Networks Association
- Electricity Commission
