The standard set of numbers every thermal station reports in its shift log and daily MIS return — Plant Load Factor, Plant Availability Factor, Auxiliary Power Consumption %, and (where fuel consumption is entered) Specific Coal/Oil Consumption — from one day's or one shift's metered totals.
Verified against published standard
Generation, Availability & Fuel
PLF here follows the CEA (Central Electricity Authority, India) convention of gross generation against installed capacity; some utilities track it on a net basis instead — enter net generation in both fields if that is your plant's convention.
Enter generation, availability, and (optionally) fuel figures to calculate.
About This Calculation
PLF, PAF, and APC% are the three numbers every thermal station's daily MIS return is actually built around, and each is a direct ratio of metered quantities — no assumed coefficient anywhere. PLF (Plant Load Factor) measures how hard the unit ran relative to its installed capacity; PAF (Plant Availability Factor) measures how much of the period the unit was even available to run, independent of how hard it was actually loaded; APC% (Auxiliary Power Consumption) measures how much of the unit's own gross output its auxiliaries (fans, pumps, mills, coal handling) consume before any of it reaches the grid.
Frequently Asked Questions
Why can PLF be low even when PAF is 100%?
PLF and PAF measure genuinely different things — a unit can be fully available (PAF 100%) all period yet still be backed down or two-shifted for grid demand reasons, giving a low PLF despite perfect availability. Conversely a unit can be highly loaded whenever it runs (high PLF-when-running) but have poor PAF due to forced outages, which is why utilities track both, not just one.
Does PLF use gross or net generation?
This calculator follows the CEA (Central Electricity Authority, India) convention of gross generation against installed capacity, which is the most common basis — but it isn't universal; some utilities and some contractual PPAs define PLF on a net basis instead, so check which convention applies before comparing this figure against a target or benchmark from another source.
Why does APC% matter commercially, not just technically?
APC% directly determines how much of the plant's gross output is actually available to sell — a plant with high APC% needs proportionally MORE gross generation (and more fuel) to deliver the same net energy to the grid, which is exactly why APC% appears in tariff and incentive/penalty structures in many regulatory frameworks, not just as an internal efficiency metric.