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UI computations. Rationale in fixing the rate. UI rate @50Hz= 155ps/u Median of of Average cost of Coal/ Lignite for 08/09-01/10 UI rate @49.7Hz= 403ps/u sufficient incentive to the generating station based on coal including imported coal UI rate @49.5Hz= 873 ps/u
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Rationale in fixing the rate • UI rate @50Hz= 155ps/u Median of of Average cost of Coal/ Lignite for 08/09-01/10 • UI rate @49.7Hz= 403ps/u sufficient incentive to the generating station based on coal including imported coal • UI rate @49.5Hz= 873 ps/u highest of the average energy charges of generating stations for 08/09-01/10
UI cap rates Generators under APM fuel: • If the UI rate in a time block exceeds 403 ps/u then the UI rate for the station is restricted to = 403ps/u Restricted cap rates • For over-generation in a time block beyond 105% of the Declared Capacity i.e. if the generation is 105% to 107% (say) then for the extra 2% beyond 105% the rate = 155ps/u • For over-generation when the generation exceeds 101% of the Declared Capacity over an entire day then for any time block in that day,when the generation is say 104% then for the extra 3% (104%-101%) the rate is = 155ps/u
UI cap rates Beneficiary or Buyer : • For Underdrawalupto10% or 250MW whichever is less = No cap • For Underdrawalbeyond 10% or 250MW shall not exceed 403ps/u • For Eg:- if AP has schedule of 100 MW,but is underdrawing at 91MW then for the 9MW the prevailing rate applies.But if it is underdrawing at 88MW and if the rate is 873ps/u (i.e. more than 403ps/u) then for 2MW (i.e. 100-10% of 100=90;90-88=2) the rate will be restricted to 403ps/u
UI cap rates For Sellers • For Overgeneration upto 120% of Schedule = No cap • For Overgeneration beyond 120% of Schedule but upto 100% of Installed capacity =403ps/u Restricted Cap Rates • For Overgeneration beyond 105% of IC in a block or 101% of IC in a day = 155ps/u
Additional UI • Additional UI is independent of individual behaviour of any constituents/ISGS/Seller • It is dependent solely on frequency. • Two frequency slabs • 49.5 Hz < SR/ER frequency < 49.2 Hz • SR/ER frequency < 49.2 Hz
49.5 Hz < SR/ER frequency < 49.2 Hz • For Beneficiary/Seller • If Overdrawing then 40 % of rate at 49.5 Hz i.e. 40% of 873ps/u • If Underinjecting then 20% of rate at 49.5 Hz i.e. 20% of 873ps/u • For ISGS • Only for underinjecting 20% of rate at 49.7 Hz i.e. 20% of 403ps/u
SR/ER frequency < 49.2 Hz • For Beneficiary/Seller • If Overdrawing then 100 % of rate at 49.5 Hz i.e. 873ps/u • If Underinjecting then 40% of rate at 49.5 Hz i.e. 40% of 873ps/u • For ISGS • Only for underinjecting 40% of rate at 49.7 Hz i.e. 40% of 403ps/u
Computation of UI • UI = Schedule – Actual • Taken from .tn1/kp1/… & .re1 files • Nuclear UI Adjustment to be taken into picture.
Nuclear UI Adjustment • Case study: • Suppose KAPS has a Schedule of 100MW.As per schedule its allocation has been split equally between KA,KL,TN,AP. • Now,let its Actual be 104MW. • So, KA gets 26MW=KL=TN=AP. • Each state gets an extra of 1MW. • If there was no nuclear UI,then let UI of each state be 100,200,300,400 MW respectively • Now, when there is nuclear UI,then the UI of each state is adjusted by 1MW. • Resultant UI becomes 99,199,299,399MW.
UI Calculation • After the nuclear adjustment is done (for all 4 nuclear PPs) this resultant/effective/total UI is from now on taken as the normal UI. • So amount for the UI = 2.5 * UI (in MW) * rate (in ps/KWh)
Calculation of restricted UI • Calculation of quantity of UI to be restricted = X (say…) • Restricted amount = 2.5*restricted rate * X • Restricted rate = 155ps/u iff prevailing rates more than 155ps/u • Valid only for ISGS & Seller
Calculation of Cap rates • For ISGS/Seller –> Quantity of UI to be capped = UI – X • Capped amount = 2.5*(UI - X)*capped rate(403ps/u)
Calculation of Cap rates • For beneficiary, Capped amount = 2.5*quantity*capped rate(403ps/u) • Quantity = beyond 10% of Schedule or 250MW,whichever is less.
Calculation of Cap rates • For seller • Rate = 403ps/u when UI > 120% of schedule but when UI < 105% of IC. • Capped amount = 2.5*UI*rate. • Quantity = UI
Additional UI • Applicable only when frequency is lower than ideal frequency band. • Amount = 2.5*rate*UI • Rate is dependent on frequency, type of constituents and overdrawal/underinjection.
Column ‘D’ • Differential amount arised from capping (due to U/D & O/I) = UI amount w/o capping – UI amount with capping
Column ‘E’ • Differential amount arised from capping = UI amount w/o capping – (restricted amount + APM capping) • Valid only for generators & Sellers
Restricting the lesser of two • When payable > receivable then payable is made equal to receivable by curtailing the payable of states only,so that total payable = total receivable.
Restricting the lesser of the two(Adjustment to non negative number) • Say, when receivable = 100 crores, payable = 110 crores. • However, in the payable column, among states say if KA only has to pay 8 crores. • When restricting,the states amount has to be curtailed by 10 crores so that payable = receivable. • In this case if it is curtailed,then KA receives 2 crores instead of paying 8 crores. • Hence, to avoid this, KA payable is made = 0,the extra 2 Crores go to SR UI Pool.