Can you go off-grid with solar energy and storage?

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Just how feasible is it for the average household to go off grid – and is it really worth it?

That's the question on the lips of many Australians considering investing in home battery technology.

With rising electricity prices and large upfront connection costs, choosing to go it alone for your electricity is becoming increasingly more attractive.

Before you cut the electricity company umbilical cord, let’s take a look at what it really means and figure out if it’s a smart move for you.

What does off-grid really mean?

The phrase off-the-grid refers to systems that have no connection with the utility grid, and must produce all electricity needed for the home by itself.

Is it possible?

Going off-grid in Australia is possible and practical in many cases, and the experience of thousands of early renewable energy pioneers and recent off-gridders confirms that.

For many off-gridders, including Emma Sutcliffe from Little River in Victoria, the decision to rely exclusively on renewable energy is borne of exorbitant costs of connecting the grid.

To date almost all of the off-gridders have been in rural locations which are not currently connected to the grid, where the cost of connection can be upwards of $30,000.

However, with the already low cost of solar energy and rapidly reducing price of battery storage technology it may well be soon viable for urban dwellers to unplug from the grid.

How many batteries and panels do I need to go off-grid?

Each situation varies depending on factors such as location, the season and of course energy consumption.

The best way to determine capacity requirements for a solar energy storage system is to have real time performance monitoring installed on your existing solar systems and household.  A Solar Analytics Smart Monitor keeps track of your solar energy system’s performance in real time (live 5 second data) and measures against a number of benchmarks, including your local weather data, providing fault alerts, diagnostics and recommendations to help you maximise the value you get from your solar system. See how much the Solar Analytics Smart Monitor can save you with our Savings Calculator.

With Solar Analytics a solar system owner knows exactly how much solar energy is being produced, how much solar energy is being consumed and how much electricity is consumed from the grid. Solar system owners can easily observe their generated solar energy and household consumed energy via their web dashboard.

This monitoring provides detailed insight into the home owner’s energy balance, and therefore the amount of battery storage required to go off the grid.

MOREWhat you need to know about solar energy battery storage

Is off-grid cost effective?

A 2015 report from global investment bank UBS has claimed the average Australian household could find it cost-competitive to go off-grid by 2018.

Using Australian-based analysts, UBS figured the current cost of switching from the grid to a solar energy storage system would be $39,000 for a house consuming the average of 19 kWh/day.

“That translates to an average cost of around 44c/kWh for the life of the system…. but assuming capital cost falls of just five per cent per annum, by 2018 it would become cost competitive for average households with staying on the grid,” the UBS report said.  In fact battery costs are falling significantly faster than 5% pa.

Australia’s Grattan Institute puts the cost of taking a home 95 per cent off the grid at $37,000, for a seven kilowatt solar system plus 35kWh of storage. But that surges to $72,000 if the same house cannot rely on a centralised network for back-up and goes off grid altogether, requiring a much larger 15kW solar system plus 85kWh of storage.

Download the Grattan Institute’s report.

However by installing energy efficient appliances and optimising your energy consumption, this can be reduced by 50% or more.

Other factors such as increasing property value can also be factored in, making the return on investment more attractive.

The hybrid alternative

Just because your system is connected to the grid that does not mean you can't benefit from storing unused solar energy.

Hybrid systems are the best of both worlds: you get the guaranteed electricity supply of the grid, with the ability to store your excess solar energy for use when the sun isn't shining.  So, instead of exporting your excess solar energy back to the grid in the middle of the day for 0-8c/kWh, you store it in your batteries and reuse it at night when you would be paying up to 55c/kWh.

With the right equipment selection, you can also switch over to your own battery reserves if the grid goes down, giving you power when your neighbourhood is in blackout. Depending on the capacity required, hybrid systems are less than half the price of a fully off-grid system and can significantly decrease the amount of energy exported to the grid.

They're still more expensive than a purely on-grid solar system, but the benefits of those batteries are persuading an increasing number of people to pay the premium.

Hybrid solar has most of the benefits of off-grid at a lower cost. It is important to match the size of the battery storage to your solar system and energy needs. The only way to do this accurately is using a comprehensive energy monitoring service such as the Solar Analytics Smart Monitor. See how it works.

While it is certainly possible for any household to off-grid, the economics are not compelling for most households. A much more financially attractive alternative is the hybrid solution, which combines solar with a smaller amount of storage to reduce the reliance on the grid. The economics of these solutions will be very dependant on energy usage and current tarrif.

There are many highly qualified energy storage suppliers such as Roof Juice, A1 Battery Pro and AGL Solar that are currently providing these hybrid storage solutions.

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