Solar Backup Power: Tesla Powerwall Review

With a continuously increasing number of home and business owners investing in solar panel systems, owners often want to know how they can best optimize their system’s production and further reduce their reliance on the utility grid. One of the most common and in-demand system upgrades is the addition of a solar battery.

As the number of solar energy companies and storage products grows to meet demand, knowing which battery system would best suit a home or business can present a challenge.

This week, we take a look at the Tesla Powerwall.

What is Tesla?

Forging its reputation in the electric car market, Tesla Motors also designs and manufactures renewable energy solutions for homes and businesses in the form of solar panels, solar roofs, and importantly—energy storage solutions.

In 2015, Tesla unveiled its first energy storage product, the Tesla Powerwall.

Key Features

Though most effective when paired with solar, the Tesla Powerwall provides the ability to store backup energy for later use with or without a solar energy system. One of the most versatile batteries on the market, the Powerwall integrates flawlessly with a wide variety of existing systems.

Other key features include:

• Stores energy during peak hours for use while the sun is down, saving customers money on utility bills
• Electric vehicle integration and charging via stored energy
• Exceptional capacity given size
• Sells excess energy back to the grid

• Automatic transfer switch (ATS) seamlessly switches a home to backup energy during a grid outage
• Automatic time-based control draws energy from the grid only when at its lowest rate
• Storm Watch feature can prioritize charging in anticipation of severe weather
• Allows system performance monitoring and control through the Tesla app
• Little to no maintenance required

Size

With a competitive usable capacity to its competitors, compact size gives the Tesla Powerwall a unique advantage to similar products. Its Lithium-ion cell battery pack is one of the most dense and high performing of any similar battery on the market, and its compact size allows mounting indoors, outdoors, in garages, or even large closets.

Additionally, the modularity of the Powerwall allows customers to install multiple batteries depending on the needs of the home– a wonderful option for those who are looking to heavily decrease their reliance on the grid.

How long will a full charge last?

• While having a backup battery system greatly lowers your reliance on the utility grid, no single battery will yield complete off-grid power for a home. Most single batteries will provide several hours’ worth of power. The Powerwall is large enough to serve as a temporary backup for a home during an outage. To be truly “off-grid,” though possible, would require the installation of multiple Powerwall batteries (typically 2 or 3).

Intelligence

The Tesla Powerwall’s superior intelligence offers a key advantage to customers looking to improve their home’s self-reliance. A few central features include:

• A Storm Watch feature which allows Powerwall to communicate to the National Weather Service and prioritize charging in anticipation of severe weather
• ATS and enabled pairing with a Backup Gateway safely and automatically disconnect a home from the grid and seamlessly transitions to backup power
• Time-based control capabilities which prompt the system to store grid power at its lowest rates (typically at night)

In addition to these benefits, Tesla continuously improves and updates Powerwall software via over-the-air programming, making sure your product stays up to date in a rapidly advancing industry.

Performance

The Tesla Powerwall provides many key home-security and financial benefits. A dense battery provides outstanding value when comparing its cost to capacity, and its liquid thermal control enables reliable charging in a variety of temperatures when compared to other similar products.

The battery also boasts an exceptional roundtrip efficiency of about 90 percent (meaning that for every 10 kilowatt-hours (kWh) of electricity put into the battery, it will output about 9 kWh).

When paired with the Tesla app, customers can even closely monitor the performance of their Powerwall. The app provides real-time data to help manage energy consumption and production, all in the palm of your hand. During a grid outage, it even allows customers to choose the appliances they would like to keep powered. This ensures the protection of the assets most valuable to each customer during a grid outage caused by a storm or extreme weather event.

Reliability

The Powerwall 2 results from over five years of research, design, product testing and evolution. Its liquid thermal control battery ensures reliable results in a variety of climates, the in-app monitoring system notifies an owner when maintenance is necessary on a system, and the ATS ensures reliable and unnoticeable transitions on and off the grid when necessary.

Tesla warranties center around two guarantees—your Powerwall will be free from defects for ten years following the installation date, and your Powerwall will retain an energy capacity of 70% (of an initial 13.5 kWh) following ten years from the install date.

Bottom Line

The Tesla Powerwall delivers as an exceptional all-around option for battery backup, with an impressive cost-to-capacity ratio relative to similar products.