A premium gated community in North Bengaluru wanted to reduce common-area electricity bills and provide future-proof EV charging for residents — without increasing the sanctioned load. TESAS designed a 500 kWh rooftop-solar-coupled BESS with 40 EV charging ports managed through a residents' app.
The 300-unit apartment community (Prestige-class complex, North Bengaluru) already had 80 EV-owning families requesting dedicated parking chargers. The RWA's existing 750 kVA transformer was already at 88% utilisation during evening peak (6–10 PM) — adding 80 × 7 kW chargers was impossible without a 2 MVA transformer upgrade costing ₹85 lakh.
Meanwhile, the common area (lifts, lobby, landscape lights, DG backup) electricity bill was ₹4.2 lakh/month — and rising. The RWA also received multiple resident complaints about power quality fluctuations during summer DG switchover.
TESAS's solution combined three elements: 300 kWp rooftop solar (charged during day), 500 kWh BESS (discharged during evening EV charging peak), and a 40-port dynamic EV charging system with power budgeting — all staying within the existing 750 kVA transformer limit.
300 kWp bifacial solar on terrace charges the 500 kWh LFP BESS during 9 AM–4 PM. BESS discharges from 6–10 PM to power EV chargers and reduce common area draw from grid.
40 × 7.4 kW Type 2 AC chargers in 3 basement parking levels. TESAS DLM limits total charger power to 200 kW at all times — served 70% from BESS, 30% from grid off-peak.
Each family sees their EV charging sessions, cost, and solar contribution on app. RWA gets a management dashboard for billing, fault alerts, and energy reports.
BESS also provides seamless UPS for lifts and lobby — eliminating the 3-second DG switchover dip that residents reported.
| Component | Specification |
|---|---|
| Rooftop Solar | 300 kWp, bifacial, 580W panels |
| Community BESS | 500 kWh LFP, 250 kW PCS |
| EV Chargers | 40 × 7.4 kW Type 2 (OCPP 2.0.1) |
| DLM Power Budget | 200 kW total EV, dynamic per port |
| App Platform | TESAS Community App (iOS + Android) |
| Billing Integration | Per-kWh resident billing via app + NEFT |
| Common Area Backup | Lifts, lobby, CCTV — UPS-grade BESS |
| Monitoring | Cloud dashboard + WhatsApp alerts (RWA) |
| Common Area Bill Before | ₹4.2 Lakh/month |
| Common Area Bill After | ₹2.95 Lakh/month |
| EV Charging Revenue (RWA) | ₹38,000/month |
| Net Monthly Saving | ₹1.63 Lakh/month |
| Annual Saving | ₹19.5 Lakh/year |
| System Payback | 4.2 years |
"TESAS solved two problems at once — our electricity bill and the EV charger demand from residents. The app makes it easy for the RWA to manage and for residents to track their charging costs. We've had zero complaints since commissioning."
TESAS's solar-BESS-EV combination lets apartment communities serve 50–200 EV chargers from existing infrastructure — with an RWA revenue stream built in.