Apcpdcl — EXtra amount on Bill as FSA

As per the methodology envisaged vide AP Gazette no.30. dt.17.07.2003 the FSA is to be computed as per the formula given below.
Fi (FSA) = (Pi X Ei+ FCi + Z+ Ai)/Qi.
Pi = P(Oct, Nov, Dec) = For example Tariff order mentions that by using 30% Hydel, 40% Thermal and 30% Gas based power weighted average power purchase price will be Rs.4/- per unit.
Actual power purchase price is Rs.5/- by using 25%Hydel, 50%Thermal, 25% Gas based power due to Srisailam unit repair, gas availability etc.
P = (Rs.5.00/- Rs.4.00/-) = Rs.1.00/-
Fi = E(oct, Nov, Dec) = Tariff order mentions 90 million units will be purchased at Rs4/- per unit. But 98 million units was purchased at Rs.5/- per unit due to increase in agricultural load. And this additional is divided among all categories as per formula.
Fci = Foct, nov, dec = for example NTPC Kothagudem Super thermal station has a fixed cost of 50 Crores for plant maintenance for Oct, nov, dec quarter allowed by Tariff order but actual cost is 100 crores due to generator breakdown. This additional cost is levied on all consumers as per ratio of division mentioned in tariff order.
Qi = Qoct, nov, dec = for example as per tariff order agricultural supply is 10%, domestic is 30%, Industrial is 30% and Commercial is 30%. But in reality Agriculture used 15%, Domestic used 35%, Commercial used 25%, and industrial used 25%. Since revenue is less due to higher domestic and agriculture use the diff is again distributed among all user as per ration except agriculture.
Ai/Qi = Steps by APCPDCL to reduce the impact of variation from tariff order by regulating agricultural loads, load shedding etc / actual energy consumed by segments even after load shedding etc.

Board Circular wording used in explanation above:
= The amount eligible for recovery through the Fuel Surcharge Adjustment formula is for the price and mix variance in the quantity of energy to be purchased as per the tariff order during quarter ‘i’.
This is to be computed for each of the month and aggregated for the quarter ‘i’
Where, Pi is the difference in the Weighted Average Variable Cost of power purchase cost in quarter ‘i’ for the power purchase quantity mentioned in the tariff order compared to the Weighted Average Variable Cost adopted in the most recent Tariff order.
Ei is the energy purchased as mentioned in the tariff order in Kwhr during the quarter to be submitted for each of the generating stations.
Fci is Difference in the Actual total fixed charges of the generating stations from the base values adopted in the most recent tariff order.
Qi is the actual energy sold to all categories (except agriculture) in the quarter Z is the changes in the cost as allowed by the Commission for a period extending in the past beyond the relevant quarter.
Ai Adjustment is to account for the financial impact of demonstrated incidents of merit order on account of controllable factors or any other events the financial impact of which, in the commission’s view should be given appropriate treatment.