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off grid system SMA 1 1Stand alone power systems (SAPS)

In situations where there is no connection to the electricity network an alternative power system is a viable option. 
Sometimes connecting to the main grid network can cost as much $25,000 per kilometre, a stand alone power system can be an attractive economic alternative.

Backing up your stand alone power system

Because Off-Grid systems are obviously NOT connected to the electricity network, some form of back-up generation and energy storage is required. 
We would advise an industrial diesel generator is an essential component for any alternative power system for when there is not enough sun/wind or water.

Minimising the need for diesel back up

Careful design of your Off-Grid System and consideration of your energy use will reduce your overall environmental impact and help reduce the use of diesel generator.  Generous battery storage will also improve the productivity of your system.

Reduce your peak electricity demand as much as possible

It's also important to consider alternative energy sources, eg:- 
  • Gas Oven
  • Wood burner (wetback)
  • Solar Water Heating
  • Marshall Water Heater
  • Passive Solar heating
  • Low Energy Appliances


Batteries store the electricity generated, they also allow you to use more electricity than you are making for a short period of time. 
Banks of lead-acid.Gel and Lithium batteries are commonly used, arranged to give between 12V and 48V. A battery bank can cost anywhere from $10,000 for an average size house and up to $30,000, depending on how much energy you need to store.

The batteries will typically need replacing in 5-18 years, depending on quality, sizing and how they are used.  (It is critical to look after your batteries!!!)

Deep cycle batteries

Batteries designed to be charged and discharged regularly are called deep cycle batteries. Their construction is different from normal car and truck batteries, which are designed to deliver a short burst of current for engine starting.

Normal engine-starting batteries would only work properly for a short period if used in a small-scale generation system.

Use the right sized batteries

Most domestic installations use DC (direct current) voltages between 12V to 48V.
Individual batteries are usually only between 2 and 12 volts and need to be arranged in an array to give the required voltage and current. Make sure you buy the right sized batteries and battery bank for your situation.

If your battery bank is too small, it may be discharged at a low level too often, which shortens its life. If the bank is too large, it will cost you more and it may not fully charge regularly, which can also shorten its life.

Typically, battery banks for wind and solar systems will be sized for several days storage, depending on the total electricity requirement and generating capacity. Hydro systems may reduce the need for battery storage if the water supply is reliable.

Battery maintenance

Batteries require a small amount of regular maintenance. This usually includes topping up batteries with distilled water (if they aren't sealed) and cleaning away corrosion, dust and dirt. We can supply a maintenance programme.


An inverter converts electricity from direct current (DC) electricity to alternating current (AC), which most household appliances use. There are two types of inverter - one for stand-alone systems and one for grid-connected systems. In both cases, advanced inverters are available that control your generation units and how much electricity your house is using at any time.

Buying an inverter

A number of inverters are available on the market and your supplier can help you choose the right size and type. We would advise an inverter/charger this options charges your batteries when there is an excess of power being generated.  For a good inverter, you should expect to pay roughly $3,000 to $10,000. A typical household would require an inverter with a capacity of around 3kW to 15kW.


The cost of installing and maintaining a stand-alone power system can vary greatly. It depends mainly upon the combination of components installed and the electricity output required.

An inverter can cost from $3,000 to over $10,000, depending on the size, quality and complexity.

A diesel generator will cost between $8,000 and $15,000 installed. The size of the generator will depend on the amount of electricity required to meet demand, the size of the battery bank and the renewable energy sources available at the site.

Full off the Grid System including installation for a AVG new build home is between 40,000.00 to 60,000.00 NZD 
Large off the grid homes with lots of electrical consumption could be up to 80,000.00 NZD including installation. we can guarantee that it will be speced correctly for your application with quality materials and installation and first make sure it designed for best performance first, with budget in mind. it is totally against our principals to install any thing substandard if we think its not right for you we will advise. 
Ring us today for a full consultation and quote today

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