DG units per litre — how to calculate genset efficiency (India)
Products · 6 min read · Updated 2026-04-21
TL;DR
DG efficiency is measured as kWh/L. Use kWh/L = load_kW ÷ diesel_L_per_hour. Track it across load levels; low-load operation usually drops kWh/L. IoT monitoring catches waste and theft.
Formula: DG units per litre
Units per litre (kWh/L) = measured electrical load (kW) ÷ diesel consumption (litres/hour).
Litres per unit (L/kWh) = 1 ÷ (kWh/L).
What is a good DG units-per-litre value?
- —Depends on DG rating, age, maintenance, and load factor.
- —Best efficiency typically near 60–80% load; poor at 10–30% load.
- —Use your own baseline and trend month-on-month rather than chasing a universal number.
Why DG efficiency drops
- —Running under low load for long hours
- —Overdue filters/injectors maintenance
- —Fuel theft or refuelling short-delivery
- —Incorrect kWh measurement (no real meter)
Frequently asked questions
Is kVA enough to compute DG units per litre?
Use kW (real power) for kWh output. If you only have kVA, estimate kW using PF: kW ≈ kVA × PF.
Can I improve DG kWh/L without changing the DG?
Yes: avoid low-load running, consolidate loads, schedule tests, and maintain filters/injectors. Monitoring ensures the changes stick.
How do I detect fuel theft using kWh/L?
Compare expected fuel burn (kWh × SFC) vs actual tank drop. Large gaps indicate leakage/pilferage.