The Challenge
A facility's electricity tariff included: off-peak ₹5/kWh (10pm–6am), standard ₹8/kWh (6am–6pm), and peak ₹18/kWh (6pm–10pm). The facility ran its main 250 kVA generator on a fixed schedule: 6pm–10pm (peak hours) to avoid peak tariffs.
What Became Visible
Cost analysis revealed that diesel cost ₹16–18 per kWh when accounting for fuel consumption, maintenance, and wear. During peak tariff (₹18/kWh), running diesel versus grid was cost-neutral. But the facility was also running diesel during demand-driven 'high-load' periods at ₹8/kWh standard rate — where diesel at ₹16–17/kWh was 2x more expensive than grid power.
What Changed
Real-time cost comparison logic implemented. Generator only auto-starts when: (1) grid tariff exceeds ₹15/kWh AND load can be supported by diesel, or (2) grid voltage drops (failure event).
How it worked: The control system received real-time tariff from the utility and compared it to calculated diesel cost per kWh. During standard ₹8/kWh periods, grid power was always cheaper. During peak ₹18/kWh, diesel became economical. The system dynamically selected the cheaper source.
Results
during low-tariff periods
±120 hours/month
from strategic sourcing
grid + diesel optimization
Energy source selection (grid vs diesel) is an economic decision, not a fixed schedule. Real-time tariff comparison optimizes for cost automatically.
Operational Reality
Most facilities run generators on preset schedules without checking if that's economical. Dynamic cost comparison usually reduces diesel operation 20–40%.