Silicon Valley-based Sprig Electric is among the first electrical contractors in the nation to pair Tesla’s Powerpack stationary battery system (earlier post) with a 350 kW commercial rooftop photovoltaic (PV) system to optimize energy savings. The pairing, installed by Sprig Electric at their corporate headquarters in San Jose, will cut the building’s total energy costs by 80-95%.
The components of the system include 1,177 solar panels that are spread over 20,000 square feet of the building’s roof top. The 500 kWh/250 kW Tesla Powerpack battery system is installed in the Sprig Electric parking lot and is connected to the grid and the PV system. In addition to five 100 kW Powerpack commercial batteries, the system includes a 250 kW inverter and a DC combiner. The footprint is approximately 10' x 16'.
The Powerpack system maximizes consumption of on-site solar power, avoids peak electrical charges, and facilitates the purchase of energy when it is the cheapest. It acts as an energy storage system for grid power and the photovoltaic system, significantly increasing the utility cost savings that Sprig Electric will realize from using solar electricity alone, thus cutting utility bills by as much as 80-95%.
Customers can use the battery’s stored electricity to reduce peak demand. The batteries are regulated to charge during a low demand period when a surplus of energy is available. They then discharge their stored power when demand is high and the rates are high. This makes for additional savings and lowers the utility bill.
The installation at Sprig Electric headquarters is regulated by a control system which looks at building loads, the amount of energy the panels are producing, and the amount of power that’s stored in the battery. It then shifts power around appropriately based on those conditions.
The recently commissioned combo PV/battery storage system installed at Sprig Electric generated 6.7 MWh of energy and saved 4.94 tons of carbon dioxide in the first 8 wintery days.
Michael Clifton, engineering/operations manager for Sprig Electric’s Energy Efficiency Division, said that both rebates and tax credits are available for the battery system purchase.