One of the most exciting announcements in the renewable energy arena has come from Elon Musk, CEO and chief product architect of Tesla Motors, and chairman of SolarCity.
His Tesla Powerwall battery system represents a game-changer in this industry sector. It is a development stemming from Tesla’s pioneering work in bringing affordable lithium-ion (Li-ion) batteries to market for the company’s successful electric vehicles – the Tesla Model X and Model S.
The Tesla Gigafactory – currently being built in Nevada in the US – will mass- produce these batteries, bringing a-step change in terms of reducing Li-ion battery costs to market.
How will this be achieved? Tesla will use its considerable automotive experience to package Li-ion batteries into attractive, space-saving wall-mounted units. The Powerwall’s design will allow batteries to be mass produced and installed safely in homes and businesses – by the tens of thousands.
Powerwall is a boon for the solar photovoltaic (PV) industry because it brings to market an electrical storage unit that’s three to four times cheaper than conventional lead acid-based batteries.
Technically, lead-acid batteries have not really improved since their introduction some 150 years ago. Now, thanks to Tesla, every solar PV installation – grid-tied or not – should be configured around electrical storage with a view to significantly improving the availability of supply and the overall return on investment (ROI) of the solution.
Unlike lead-acid batteries that degrade drastically if discharged by more that 30-40%, depth of discharge (DoD) is no longer an issue with the Tesla Powerwall.
Li-ion holds great promise, as the battery can be fully discharged in every cycle. What’s more, the Tesla Powerwall will last as long as 20 years and comes standard with a 10-year guarantee.
Good news is that in South Africa there is currently no import duty on Li-ion batteries (unlike automotive lead-acid batteries) bringing solar PV systems ever closer to economic viability and parity in terms of costs with increasingly expensive Eskom power.