And in the US Tesla says its “gigafactory” in Nebraska will pump out 50 gigawatt hours of batteries each year, targeting a massive market of two billion homes.

AGL’s timing was fortuitous. It announced its Power Advantage proposition, will include a range of battery storage devices based on lithium-ion technology, promising clean, compact and reliable storage in the home.

Battery storage is vital for solar, saving the power generated in daylight hours for peak usage times at night.

AGL is the first major supplier into the local market, and will initially target models for residential home and small business, giving consumers more control over managing their energy consumption.

AGL’s energy storage lead, Ed Lynch-Bell says, the batteries are still an emerging technology, but is moving very quickly, so AGL wants to be at the very edge of innovation.

“The launch of Power Advantage is another pillar of AGL’s multi-pronged strategy of being a leader in the evolving new energy and disruptive technology space,” he said.

“The first device will be capable of storing six kilowatt hours of solar energy and will suit an average family home with 3-4.5 kW of solar photovoltaics.

“The battery storage device, however could be used in a home without solar PV. The battery will be the size of a large suitcase and will provide consumers with backup for essential home services such as lighting, refrigeration and communications, a welcome peace of mind for potential disruptions of energy supply.”

The battery packs, made by a leading international consumer electronics manufacturer that AGL has declined to name, have been tested by AGL and the energy firm says will be backed by an extended warranty and a range of financing plans.

“AGL’s aim is to provide tailored energy solutions for consumers which integrate energy generation and storage,” Lynch-Bell said.

“For example, with real time monitoring of a home’s solar power system and the right storage device to suit a consumer’s needs, AGL energy storage devices will enable a consumer to store power and use it when they want.”

AGL, which wants to end its coal investments by 2050, plans to develop a suite of products to cater to a range of home and business sizes and types.

The 6kWh battery storage device is the first in this range and in the initial phase will be available in limited numbers. Larger battery sizes will be available later this year.

Tesla’s batteries are designed to store up to 10 kWh of power.

The company is leveraging the battery technology they've developed for its electric cars to enable more people to switch to renewable power for their homes.

Tesla will offer a 7kWh version at an estimated cost of $US3000 [$A3800] and while the 10kWh version will cost $US3500.

They can deliver power at a continuous rate of 2kW, with peaks up to 3kW.

The batteries will be warrantied for 10 years.

Tesla is investing heavily in its gigafactory in Nebraska, as is the state with tax incentives of $US1.3 billion, and it needs to convince hundreds of thousands of consumers per year to buy its cars and battery products.

Tesla forecast that prices for its batteries will fall by half within five years.

Tesla wants its PowerWall batteries to fundamentally change the way the world uses energy, Tesla founder Elton Musk has said.

Musk also wants to colonise Mars

The long-term goal is to reduce the world's reliance on energy generated from fossil fuels while creating regional networks of home batteries that could be controlled as if they were a power plant. That would give utilities another way to ensure that they can provide power at times of peak demand.

The gigafactory will be complete by 2017.