The new Tesla Energy Powerwall Home Battery during an event at Tesla Motors in Hawthorne, California, April 30, 2015. Tesla unveiled Tesla Energy — a suite of batteries for homes, businesses, and utilities — a highly anticipated plan to expand its business beyond electric vehicles.
While wind and solar power have made great strides in recent years, with renewables now accounting for 22% of electric energy generated, the issue that has held them back has been their transience. The sun doesn’t shine at night and the wind doesn’t blow year-round — these are the mantras of all those opposed to the progress of renewables.
Now the renewable-power billionaire Elon Musk has just blown away that final defence. Last Thursday in California he introduced to the world his sleek new Powerwall — a wall-mounted energy-storage unit that can hold 10 kilowatt hours of electric energy, and deliver it at an average of 2 kilowatts, all for $3,500.
That translates into an electricity price (taking into account installation costs and inverters) of around US$500 per kWh — less than half current costs, as estimated by Deutsche Bank.
That translates into delivered energy at around $0.06 per kWh for the householder, meaning that a domestic system plus storage would still come out ahead of coal-fired power delivered through the conventional grid.
What’s more, Musk is going to manufacture the batteries in the US, at the “gigafactory” he is building just over the border from California in Nevada.
He is not waiting for some totally new technology, but he is scaling up the tried-and-tested lithium-ion battery that he is already using for his electric vehicles.