Tesla recently unveiled its Powerwall battery system that aims to change the way we use and store energy in our homes. However, Bloomberg is reporting that the 7kWh Powerwall doesn’t yet work well with rooftop solar power sources, which could be a major issue for early adopters hoping to use it as a way to store energy generated by rooftop solar panels. In fact, Bloomberg says that even SolarCity — the solar power supplier that’s chaired by Tesla CEO Elon Musk — won’t be supporting the 7kWh version of the Powerwall when it launches.
“SolarCity, with Musk as its chairman, has decided not to install the 7kWh Powerwall that’s optimized for daily use,” Bloomberg writes. “[A SolarCity spokesperson] said that battery ‘doesn’t really make financial sense’ because of regulations that allow most U.S. solar customers to sell extra electricity back to the grid. For customers of SolarCity, the biggest U.S. rooftop installer, the lack of a 7kWh option means that installing a Tesla battery to extend solar power after sunset won’t be possible.”
The good news is that SolarCity will offer the 10kWh battery to customers who are buying rooftop solar systems. The 10kWh Powerwall costs $3,500, which is $500 higher than the $3,000 that Tesla is charging for the 7kWh battery. Tesla expects to start shipping both batteries this summer.