A commercial customer needed a reliable backup power solution to protect critical IT infrastructure from grid outages. The solution combined 117 kWh of Pytes V12 battery storage with a three-phase Victron inverter/charger system, external transfer switching, and the customer's existing rooftop solar PV.
Just one day after installation, the entire surrounding industrial estate experienced a power outage. The customer's critical IT systems stayed online. The system supported infrastructure relied upon by approximately 80 people, allowing the business to continue operating while neighboring facilities were without grid power.
For this customer, a grid outage meant more than losing lights or general building power. Critical IT infrastructure needed to remain operational to support day-to-day business activity. Even a short interruption could affect communications, system access, and business continuity. The customer also already had rooftop solar installed, creating an opportunity to integrate existing generation into the backup strategy rather than build a completely separate energy system.
The project needed to provide:
i）Reliable backup for critical IT loads
iii）Integration with existing rooftop solar
iiiii）A practical installation approach for the onsite contractor
The project was built around 117 kWh of Pytes V12 battery storage paired with a pre-built Victron power system designed and assembled by Callidus.
| Item | Configuration |
|---|---|
| Application | Critical IT Backup / Business Continuity |
| Battery | Pytes V12 |
| Battery Capacity | 117 kWh |
| Inverter/Charger | 6 × 15 kVA Victron MultiPlus-II |
| Architecture | Three-Phase, 2 Units per Phase |
| Inverter Capacity | 30 kVA per Phase / 90 kVA Total |
| Solar | Existing Rooftop PV |
| Transfer | External Transfer-Switch Architecture |
| System Builder | Callidus |
| Installation | Callidus Trade Partner |
During a grid outage, the transfer-switch architecture allows the site's critical loads to operate from the battery-backed system. If solar generation is available during an extended outage, the existing rooftop PV can continue contributing energy, helping extend the available battery runtime.
The Victron power system was designed, assembled, and tested by Callidus before delivery to the site. The completed system was then installed by one of Callidus' trade partners.
This pre-built approach moves much of the system integration and assembly into a controlled environment, allowing the onsite installer to focus on:
i）Battery installation ii）AC connections iii）Transfer switching iiii）Solar integration iiiii）Final commissioning
For commercial projects, this approach can help reduce onsite complexity while supporting a more consistent installation process.
The system was put to the test almost immediately. Just one day after installation, the entire industrial estate experienced a power cut. While surrounding facilities lost grid power, the customer's critical IT infrastructure remained operational. The Pytes V12 battery system and Victron inverter platform performed as intended, helping support systems used by approximately 80 people and allowing the business to continue operating during the outage. For the customer, the value of the system was demonstrated almost immediately.
Commercial battery storage is often evaluated in terms of solar self-consumption, time-of-use optimization, and electricity cost savings. For many businesses, however, resilience can be just as important as energy savings. In this project, battery storage provides an additional layer of protection for business-critical infrastructure. During normal operation, the customer can continue using its existing rooftop solar as part of its overall energy strategy. During a grid outage, stored energy provides backup power, while available solar generation can help extend system autonomy. The result is a commercial energy storage system designed not only to manage energy, but also to help protect business operations.
This project demonstrates the value of commercial energy storage beyond solar utilization alone. By combining 117 kWh of Pytes V12 battery storage, a flexible Victron three-phase architecture, and existing rooftop solar, the customer gained a backup system designed to keep critical infrastructure operating when grid power is unavailable.
And in this case, it took just one day for the system to prove its value.
Learn more about Callidus and its pre-built power systems:
Explore Pytes energy storage solutions:
https://www.pytesusa.com/
