Tesla Motors plans to produce a wall-mounted battery pack designed to store renewable energy in the home. Tesla CEO Elon Musk revealed the Powerwall unit on April 30. The unit, he says, will go into small-scale production in three to four months at the company's Fremont, Calif. plant. In 2016, the unit will be produced at the company's battery factory in Nevada, which is currently under construction.

The lithium-ion, software-equipped Tesla Powerwall comes in two versions: a 7 kilowatt-hour pack for $3,000 and a 10 kilowatt-hour pack for $3,500. Those fees don't include installation. Either version will power a typical U.S. home during peak evening hours, the company says.

It works indoors or outdoors and has a 10-year warranty. It weighs 220 pounds and measures 52.1 inches by 33.9 by 7.1.

The device is designed to allow homeowners with solar panels on their roofs to store electricity generated throughout the day for use at night or during power outages. SolarCity is another Musk-led company that installs and owns rooftop solar photovoltaic systems.

SolarCity will incorporate the battery into its DemandLogic energy storage system. DemandLogic, which is being adopted by several of the largest retail, biotech and Internet companies in the U.S., allows businesses to reduce energy costs by using stored electricity to reduce peak demand, and can also provide backup power during grid outages.

SolarCity also says it will incorporate the battery into its GridLogic microgrid service. GridLogic combines distributed energy resources, including solar energy systems, batteries and controllable load. For residential solar customers, SolarCity saays it will provide a turnkey battery backup service that includes permitting, installation and ongoing monitoring.

The Powerwall battery will be available in 10 kWh weekly cycle and 7 kWh daily cycle models. The company says both will be guaranteed for 10 years and are sufficient to power most homes during peak evening hours. Multiple batteries can be installed.

Tesla says the unit is a wall-mounted, rechargeable lithium ion battery with liquid thermal control. The company claims a 92% round-trip DC efficiency, and says the unit generates 2.0 kW continuous, 3.3 kW peak at 350-450 volts. Current is 5 amp nominal, 8.5 amp peak output, and Tesla says the unit is both single-phase and three-phase utility grid compatible. The unit is UL listed.

To contact the author of this article, email engineering360editors@globalspec.com