Tesla, better known for it's innovative development of electric cars, has now released the new Powerwall battery storage for storing power sourced from the sun. The introduction of solar panels has really taken off in Australia with several cities experiencing up to 6 hours of peak sun shine per day. However the larger percentage of consumption occurs at night and so the concept of being able to store the solar energy, sourced during the day, for use at night becomes attractive. Another advantage is that households would be insulated from power grid blackouts.

The cost in Australia for a 4Kw solar panel system and a 7kW Powerwall (installed) is around $16500. For those that already have solar panels installed the option to purchase just the Powerwall is around $9500 (installed) - depending on the compatibility of the existing inverter. The installation component is about $1000. The inverter converts DC power produced by the solar panels to 240V AC suitable for household consumption. The batteries are guaranteed for 10 years.

With battery storage at these prices the concept of "going off the grid" is becoming more viable for Australian households. However it should be noted that the average electricity consumption per household could not be sustained with just one 7kW Powerwall installed. More Powerwalls can be added into the system in order to increase capacity. Each household's consumption and circumstances are different. The average daily consumption for an average 3 person household is around 20kWh. Battery storage should be considered as a supplement rather than a replacement to the grid, at current prices. In most cases households with batteries should source about 90% of their energy requirements from solar as opposed to about 35% with solar panels only.