US electric carmaker Tesla Motors has unveiled
batteries that can power homes and businesses as it is trying to expand beyond its electric
cars business. Tesla’s home battery system is named as “Powerwall”. Tesla Powerwall is a rechargeable lithium-ion
battery designed to store energy at a residential level for load shifting, backup power and
self-consumption of solar power generation. Powerwall consists of Tesla’s lithium-ion
battery pack, liquid thermal control system and software that receives dispatch commands
from a solar inverter. The unit mounts seamlessly on a wall and is
integrated with the local grid to harness excess power and give customers the flexibility
to draw energy from their own reserve. The average home uses more electricity in
the morning and evening than during the day when solar energy is plentiful. Without a
home battery, excess solar energy is often sold to the power company and purchased back
in the evening. This mismatch adds demand on power plants and increases carbon emissions.
Powerwall bridges this gap between renewable energy supply and demand by making your home’s
solar energy available to you when you need it. Current generation home batteries are bulky,
expensive to install and expensive to maintain. In contrast, Powerwall’s lithium ion battery
inherits Tesla’s proven automotive battery technology to power your home safely and economically.
Completely automated, it installs easily and requires no maintenance. Power companies often charge a higher price
for electricity during peak evening hours than overnight when demand is low. Powerwall
can reduce your power bill by storing electricity when rates are low and powering your home
when rates are high. Tesla will sell the 7kWh unit for $3,000 , while
the 10kWh unit will retail for $3,500 to installers. They go on sale in September, and the price
does not include the inverter or the installation.