In April Tesla Motors announced their newest product, Powerwall: a home battery and then some. There has been a lot of buzz over the lithium-ion battery designed to charge and store energy generated from solar panels. Tesla, a multi-industry leader in the fields of energy storage, battery charging, and welding technology, has always been innovative.
Their big announcement may have created curiosity among the public, but we still have questions. Is their Powerwall just cool technology or really worth the investment for your home?
Tesla is offering the home battery in two sizes, 7 kWh or 10 kWh (kilowatt-hour). The batteries are designed for load shifting, which means they charge and discharge energy according to rates based on electrical demand. They will charge when electricity prices are low due to less demand and will discharge when rates are high – morning, afternoon and early evening especially during the summer months. Powerwall also stores any surplus energy generated for use later, whether it’s at night or during a power outage. The 7kWh battery is designed for daily use, while the larger 10kWh is meant to be used as a backup system. These sleek batteries are designed to be mounted on the wall, inside or outside, and can be stacked sideways – they are even available in different colors to match the Tesla Model S car.
Although Tesla’s home battery sounds pretty great, it may not make sense financially. The 7kWh Powerwall battery costs $3,000 and the 10kWh is $3,500, not including the price of installation, control software, or inverter costs. Plus, even something as innovative as the Powerall comes with limitations. The low capacity of the smaller home battery means you will most likely need to install several, which can get extremely expensive at $3,000 a battery. Also, due to net metering, a policy in which utilities are required to buy back excess solar energy, it does not financially make sense to use the batteries for storage. For now, anyway!
There are other places in the US that can benefit from the Powerwall. For example, Hawai’i’s average cost of electricity on the grid was more than twice the average of the rest of the country in March, according to the US Energy Information Authority. In California, tiered energy rates gives homeowners an allotted amount of energy per month – once that is used up (usually within 15-20 days) they move on to the next, more expensive per kWh tier. This makes saving energy and harnessing solar power the far more affordable option.
This is just the beginning for Tesla and their home batteries. They are currently building a $5 billion battery factory in Nevada, called Gigafactory. Once the factory is up and underway there’s bound to be progress, so stay tuned!
Contact SunBlue Energy today to learn what solar energy options are best for your home!