What about reliability — DG vs BESS?

BESS grid-to-island transfer is under 20 milliseconds — fast enough that computers, servers, refrigeration, and OT equipment don't notice. A DG ATS takes 5–10 seconds, long enough for elevators to stop, processes to interrupt, and lights to drop. BESS also has higher reliability over time (no fuel supply, no fuel theft, no engine wear).

Cost comparison · 10-year TCO

Diesel generator vs battery storage — the real cost comparison.

For a typical 60 kW Indian load running 8 hours a day, the 10-year total cost of a diesel generator approaches ₹1 crore. An Infozeb BESS + solar combination comes in at ₹45–60 lakh. Here are the line items.

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10-year delta · 60 kW load

₹50L+saved

Before counting maintenance, CPCB CEMS instrumentation, engine overhaul, and the reputational cost of fumes and noise during outages.

Line-by-line TCO

10 years. Same load. Two paths.

Assumptions: 60 kW critical load, 8 h/day operation, diesel at ₹100/L, BESS+solar charges from rooftop PV + trickle grid. Real numbers vary ±15% by site — verify with the calculator.

Cost line · 10 years	Diesel generator	Infozeb BESS + 80 kWp solar
Capex (one-time)	₹4–6L (60 kVA DG + ATS)	₹40–55L (IZ-60K-3P + 80 kWp solar)
Diesel fuel · 10 years	₹1.75 Cr (17,520 L/yr × ₹100)	₹0
Maintenance + AMC · 10 yr	₹12L (₹1.2L/yr)	₹3.5L (₹35k/yr)
CPCB CEMS · 10 yr	₹2.5L (instrumentation + audits)	—
Engine overhaul (year 5)	₹3L	—
Battery cell warranty extension (year 10)	—	₹1.5L (optional)
Diesel pilferage / shrinkage	₹0.4–0.8L/yr typical	Zero
Cost per unit (₹/kWh produced)	₹18–22	₹2–3
Total 10-year outflow	₹95L–1.1 Cr	₹45–60L (capex-amortised)

Diesel-only sites with three-shift operations (24×7) approach ₹3 crore over 10 years. The math gets worse the longer the load runs. Use the calculator for your specific load profile.

Beyond cost

Noise, emissions, and the things you can't un-smell.

The TCO table understates the picture. Diesel comes with externalities — air-quality enforcement, noise complaints, guest experience, ESG reporting exposure — that don't show up on a P&L line.

Dimension	Diesel generator	Infozeb BESS
Operating noise at 1 m	~75 dB (loud truck idling)	Under 50 dB (refrigerator)
Local emissions during run	NO₂, PM2.5, CO, CO₂, ~2.68 kg CO₂/L	Zero
GRAP / AQI emergency operation (NCR)	Restricted or banned	Permitted, no impact
Audit risk (Pollution Control Board)	Active enforcement above 62.5 kVA	Not applicable

Reliability

The half-second nobody talks about.

A DG ATS gap of 5–10 seconds is long enough that lifts pause, computers reboot, and OT monitors flicker. BESS islanding closes in under 20 milliseconds — fast enough that no load notices.

Operating dimension	Diesel generator	Infozeb BESS
Grid-to-backup transfer time	5–10 seconds (ATS)	Under 20 milliseconds
Effect on connected loads	Computers reboot, lifts pause, OT briefly drops	No effect — load doesn't notice
Fuel supply dependency	Daily / weekly diesel deliveries	Solar + grid · no logistics
Operation in 48°C ambient	Derated, harder starts	Active thermal management
Maintenance windows	Quarterly oil change, half-yearly service	Remote diagnostics, predictive alerts

Frequently asked

Buyer questions, answered.

How much does a diesel generator actually cost over 10 years?

A 60 kW DG running 8 h/day in India costs roughly ₹95 lakh over 10 years — ₹17.5L/year on diesel fuel alone (at ₹100/L), plus ~₹1.2L/year on maintenance and AMC, plus the ₹2–4L CPCB CEMS instrumentation now mandatory above 62.5 kVA, plus periodic engine overhauls.

What does an Infozeb BESS + solar replacement cost over the same period?

Roughly ₹10–14 lakh over 10 years — primarily ₹35,000/year in BMS / EMS monitoring and minor O&M. The capex is typically ₹40–55L for IZ-60K-3P + 80 kWp solar, paid back in 3–4 years on diesel savings alone.

Is the cost-per-unit gap really 7–10×?

Yes. A typical 60 kW DG consumes 15 L of diesel per hour at full load. At ₹100/L, that's about ₹18–22 per kWh produced. An Infozeb BESS charged from solar plus trickle grid runs at ₹2–3 per kWh — a 7–10× cost advantage on a like-for-like basis.

Can I keep the DG as standby and use the BESS primarily?

Yes — the most common deployment. BESS handles 95% of outages and peak shaving; the existing DG stays in place for multi-hour blackouts. Many sites then shrink the DG to a smaller standby unit, avoiding the CPCB CEMS instrumentation requirement entirely.

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