Sunpower has introduced two new storage systems for residential rooftop photovoltaic (PV) systems. The two devices, named SV-BASE13-C and SV-BASE19.5-C, are from the company’s SunVault series. According to the company’s statement, with this launch, SunVault is now available in five configurations: 13 kWh, 19.5 kWh, 26 kWh, 39 kWh and 52 kWh. The maximum usable energy of the SV-BASE13-C storage system is 12 kWh, with a storage capacity of 13 kWh. It weighs 217 kg and has dimensions of 164 cm x 71 cm x 36 cm. Meanwhile, the maximum usable energy of the SV-BASE19.5-C battery is 18 kWh, with a storage capacity of 19.5 kWh. It weighs 267 kg and is the same size as the SV-BASE13-C system. With a round-trip efficiency of over 86 per cent, both lithium-ion systems use lithium-iron-phosphate (LiFePO4) as the cathode material. Their maximum output (AC) for continuous backup current is 28.3 A, and their nominal internal voltage is 51.2 V. Both batteries have a protection rating of IP54 and can operate in temperatures between -20 °Celsius and 45 °Celsius. Reportedly, the new products come with a 10-year warranty and can operate for unlimited cycles.