The pairing of solar photovoltaics and energy storage batteries is one of the most exciting new trends in the market today. Perhaps the best-known storage system, the Tesla Powerwall, appeals largely to homeowners and small business owners interested in how renewable energy can help reduce their electricity bills, provide backup power, and manage their energy use. Since I recently received training as a Tesla Powerwall certified installer, I’d like to help our customers understand more about the product and how to install it.
What does Tesla Powerwall do?
Tesla Powerwall is an energy storage device that uses lithium-ion battery technology. The most common use for Powerwall is self-powering a home. Designed to work seamlessly with solar systems, it can be either installed at the same time as a solar PV system or retrofitted on homes that have an existing solar system. Combined with a solar array, Powerwall allows owners to store the power they generated during the day and use it at night, potentially eliminating the need for grid power from their utility. The storage system can also be used for backup power, home energy monitoring, and time-of-use load shifting.
One Powerwall unit can store about 14 kilowatt-hours (kWh) of energy. That means on a single charge, a Powerwall can sustain a 1 kW load (about 16 60-watt lights) for 14 hours. The average American home uses about 25 kWh of electricity every day, so many customers who want their home to be self-powered will install a solar system along with two Powerwalls, which would double the amount of energy they can store. During the day, the energy produced by the solar system will power the loads in the home and charge the Powerwall units; during the night, the loads will be powered by the storage system.
When Powerwall is utilized for home energy monitoring, the system can help the owner see where and how energy is being consumed in the home. Tesla’s mobile app shows the user his or her energy use habits and where energy use can be cut down. Another function is time-of-use load shifting, which should appeal to customers who pay peak rates to their utility. Users will be able program their Powerwall to power their homes during peak rate periods and to charge the storage system when the rate is low.
Installation process
Tesla Powerwall requires installation by a certified installer in order to validate the warranty. In addition to the lithium-ion battery pack, the Powerwall system consists of a liquid thermal control system, an integrated inverter, and software. The unit mounts seamlessly on a wall or on the ground and is connected to the grid to export excess energy, maximizing the opportunity for economic benefit.
Installations usually take less than a day to complete, and homeowners are able to begin operating their system right away. Before the day of installation, a home energy assessment must take place, which will cover all details needed by the installer to complete installation. This can take place over the phone or in person. If done over the phone, the customer will need to provide images of their main service panel, solar array and inverter, if applicable, as well as potential locations for Powerwall to be installed.
During the process the installer will contact the utility and instruct them to de-energize the home so that the electrician can safely work inside the main service panel. The installer will perform all the necessary work, including mounting the unit, putting in new circuit breakers, installing new circuits in conduit, and integrating the existing solar system, if needed. Installers are trained to make the installation look as sleek and attractive as possible.
Once Powerwall is physically installed, the electrician will restore power to the home and commission the system. An Internet connection is required for commissioning and operation of the unit. Critical software updates are sent to the unit through this connection, and the Tesla mobile app controls the unit through this connection as well. Once the unit has been commissioned, the customer can start using the new energy storage system.
How do I get Tesla Powerwall or become a certified installer?
If you are an electrician or solar specialist who would like to become a Tesla Powerwall certified installer, the Inovateus Solar team can help arrange that for you. We already have two team members who have become Powerwall certified installers, but the two of us won’t be able to handle the expected strong demand for these products. With the large amount of interest that Powerwall and energy storage in general are generating, we will need several more electricians among our customers and partners to become certified installers. Training typically takes place at a Tesla facility—I took the course in Hartford, CT—and requires less than one day to complete.
If you are interested in having Tesla Powerwall installed at your home or business, then give us a call us or send us an email. Our supply and distribution team gets contacted regularly by interested homeowners who are eager to purchase a system, so we anticipate selling many of these units soon.
By Jonny Rienks, design engineer and Tesla Powerwall certified installer, Inovateus Solar
