In spring 2015 Tesla unveiled its Powerwall battery system for homes and businesses – a 110-kilogramm flat battery pack in an aesthetic design that can be installed on a wall [indoors or outdoors].
Elon Musk – CEO and product architect of Tesla Motors – announced the Powerwall storage system at $3,000 for the 7 kilowatt hour (kWh) battery and $3,500 for the 10 kWh model [not including the installation costs].
The Powerwall does two things: It stores solar energy if you have solar panels and it stores energy from the grid when electricity is cheapest. Off-peak-storage is interesting in countries where utilities have time-of-use dynamic pricing. If you’ve already solar panels on your house you can essentially go off the grid.
Multiple Powerwalls can be grouped to 90 kWh total for the 10 kWh battery and 63 kWh total for the 7 kWh battery. The battery continuously generates 2.0 kW and 3.3 kW during peak usage.
The Powerwall units will be able to be connected to the internet, so owners can access management software and stats and can link their batteries into micro-grids. This means, that Powerwalls can contribute to the ballance of the power grid to support supply and demand.
Tesla is making inroads into the energy market with massive promises. After one week on its earnings conference call, Elon Musk mentioned that they already received 38,000 reservations for the home system and 2,500 reservations for the much bigger, commercial-scale battery systems.
Analysts at Bloomberg did the maths and estimated that all these reservations are worth approximately $800 million in potential revenue for Tesla, if they convert to sales.This sounds like an overestimate, but a spokeswoman for Tesla said that the numbers „look right“.
So how much is that battery power going to cost? For a 7 kW lithium-ion system with an initial cost of $428 per kwh capacity, 92% efficiency and ability to run 5,000 cycles, the cost of stored electricity will be at best 10 cents per kilowatt hour. Read the article at CleanTechnica.com: Tesla Powerwall & Powerblocks Per-kWh Lifetime Prices
The Tesla home batteries went on sale in the US in late summer 2015.
Tesla is going to build a Gigafactory in Brandenburg, Germany.