Bulk System Incremental Losses - BC Hydro - Transmission

INFORMATION RELEASEPEAK LOAD INCREMENTAL LOSSESFOR THE BULKTRANSMISSION SYSTEMOverviewThis information release provides the bulk transmission Peak load incrementallosses and system loss load factors along with the methodology for computingcapacity losses and energy losses associated with new generation capacityadditions to serve future load.BCTC is committed to continuing to provide relevant, timely information aboutBC’s transmission system. BCTC will update this information as new significantchanges are observed in the load forecast, generation acquisition andtransmission system.Market OperationsE-mail: bctc.interconnection@bctc.comPhone: (604) 699-7381FAX : (604) 699-7539IntroductionThe peak load incremental losses for bulk transmission paths and system lossload factors are computed for the years 2011/2012 and 2014/2015. The powerflow base case for winter peak of 2011 is chosen because all the contractedF2006 Open Call for Power generation is scheduled to be on line by that year.The power flow base case winter peak of 2014 is chosen because the Nicola toMeridian 500 kV transmission line (5L83) is planned to be in service by that year.Data and system configurationThe network configurations include the upgrades identified in the BCTCTransmission System Capital Plan, the BC Hydro Base Resource Plan providedin August 2007 and the December 2006 Load forecast. The Demand SideManagement levels EE 3, 4 and 5 were also modelled. The voltages at major500 kV buses are maintained at 1.05 per unit during the computations. Thegeneration despatch from the interior remote regions is proportional to theirmaximum capacity ratings to serve the system load. The generation and loadvalues used in the study are shown in Table 1.Transmission System PlanningPage 1 of 627/11/2007

INFORMATION RELEASEPEAK LOAD INCREMENTAL LOSSESFOR THE BULKTRANSMISSION SYSTEMTable 1: BC Hydro Generation, load, losses and loss load factorsYearYearCoastalMWGenerationPeaceMWColumbiaMWLoad MWNet IntertieexchangeMWLosses2011/12 2059 3663 5320 10024 274 7442014/15 2349 3587 5150 10061 358 666The Peace generation consists of resources in the Peace region, North Coast,and Central Interior sub zones and portions of the Kelly Nicola region electricallyconnected to Kelly substation. The Columbia generation consists of resources inthe East Kootenay, Selkirk area, and portions of the Kelly Nicola regionelectrically connected to Nicola substation. The Coastal generation consists ofresources in the Lower Mainland and Vancouver Island regions.Peak Load Incremental LossesThe Peak Load Incremental Losses (PLIL) across each bulk transmission pathshown in the diagrams is computed by incrementing the base path flow by 200MW. The PLIL for the year 2014 are lower compared to 2011 from the Peaceand Selkirk regions. This is due to higher coastal generation additions by 2014resulting in less dispatched generation from remote regions and also furtherreduction in system losses due to addition of the 5L83 transmission line.Transmission System PlanningPage 2 of 627/11/2007

INFORMATION RELEASEPEAK LOAD INCREMENTAL LOSSESFOR THE BULKTRANSMISSION SYSTEMBCTC Bulk transmission system Peak LoadIncremental Losses (PLIL) for the year 2011-2012Peace River(PR)PLIL: 5.21%North Coast(NC)PLIL: - 0.3%Williston(CI)Selkirk(SE)PLIL: 0.30%EastKootenays(EK)PLIL: 4.21%PLIL: 4.21%Kelly LakeNicolaPLIL: 6.02%PLIL:7.45%VancouverIsland(VI)PLIL: 0.55%LowerMainland(LM)Transmission System PlanningPage 3 of 627/11/2007

INFORMATION RELEASEPEAK LOAD INCREMENTAL LOSSESFOR THE BULKTRANSMISSION SYSTEMBCTC Bulk transmission system Peak LoadIncremental Losses (PLIL) for the year 2014-2015Peace River(PR)PLIL: 5.08%North Coast(NC)PLIL: 0.15%Williston(CI)Selkirk(SE)PLIL: 0.30%EastKootenays(EK)PLIL: 3.98%PLIL: 4.03%Kelly LakeNicolaPLIL: 4.94%PLIL:5.39%VancouverIsland(VI)PLIL: 0.65%LowerMainland(LM)Notes:1. The arrows indicate the typical direction of flow from region to region.2. PLIL = Peak Load Incremental Losses3. PLIL are additive from region to region. For example, PLIL from NC to LM:PLIL T = -0.15%+3.98%+4.94%=8.77%Transmission System PlanningPage 4 of 627/11/2007

INFORMATION RELEASEPEAK LOAD INCREMENTAL LOSSESFOR THE BULKTRANSMISSION SYSTEMMethodology for losses calculationThe methodology for calculation of bulk transmission capacity and energy lossesassociated with a generation addition is described below.1. The bulk transmission capacity losses are calculated by summing thePeak Load Incremental Losses from the point of delivery to the point ofreceipt multiplied by the generating capacity.2. The bulk transmission energy losses are calculated by using the followingformula: Energy losses =capacity losses X 8760 X LLF X K3. LLF is provided in Table 2 based on a power flow with a historical Loadpattern of F2007 assumed to remain the same for the years 2011 and2014.4. This K factor modifies the generator capacity factor, when it is differentfrom the load factor. An approximation to account for generator that has adifferent capacity factor than the load factor is given by the formulaK=CF/LF5. LF = Average load / Peak hour load6. CF = (Sum of Annual MWH energy provided by the added generator)/(8760* rated Capacity of generation in MW).DISCLAIMERTable-2: System Load Factors and Loss Load FactorsYearLoad Factor Loss Load(LF) Factor(LLF)2011/12 0.65715 0.475222014/15 0.65715 0.47575The incremental losses and loss load factors provided in this note are approximationsbased on the methodology described. The methodology described in this note is notnecessarily comprehensive given the complexity and uncertainty of the future powersystem. The information set out in this Information Release is based on a number ofassumptions, only some of which have been identified. Changes to relevant factors maymake those assumptions invalid, and the incremental losses and loss load factorsevaluation may differ substantially from those presented here.Accordingly, BRITISH COLUMBIA TRANSMISSION CORPORATION (“BCTC”) MAKESNO WARRANTIES, EXPRESS OR IMPLIED, WHETHER ARISING BY OPERATION OFLAW, COURSE OF PERFORMANCE OR DEALING, CUSTOM, USAGE IN THE TRADEOR PROFESSION, OR OTHERWISE, INCLUDING WITHOUT LIMITATIONWARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSETransmission System PlanningPage 5 of 627/11/2007

INFORMATION RELEASEPEAK LOAD INCREMENTAL LOSSESFOR THE BULKTRANSMISSION SYSTEMWITH REGARD TO THE ACCURACY, CONTENT, OR CONCLUSIONS OF THISINFORMATION RELEASE.Any use of this Information Release, and any interpretations, opinions, conclusions,decisions or assumptions reached or made based on or in reliance on, in whole or in part,on this Information Release, is solely at the risk of the party making such use of thisInformation Release, without recourse to BCTC or its directors, officers, employees oragents. In no event will BCTC or its directors, officers, employees or agents be liable forany damage, injury or loss that is in any way connected to this Information Releaseincluding without limitation any indirect, special, incidental, punitive or consequentialdamages of any kind including loss of revenue, loss of profit or cost of capital.This Information Release is not intended and shall not be interpreted to constitute anyagreement by BCTC to provide any service or pursue any transmission systemreinforcement project either at this point in time or in the future.Transmission System PlanningPage 6 of 627/11/2007