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General form of generation measure savings algorithm:For non-gas generation facilities:?kWhyr=(HR0?-HR1)?HR0×kW0×LF×Hours?+(HR0?-HR1)HR1×(kW1?-kW0)×LF×Hours?For gas generation facilities:?kWhyr=(HR0?-HR1)HR1×(kW1?-kW0)×LF×Hours??Btuyr=(HR0-HR1)×kW0×LF×Hours?Percent HR improvementExampleHR0HR1Input0 MBtuInput1 MBtuMW0MW1Existing Cap.New Cap.Savings MWhSavings Mbtu11000090007008630710010010%11%7008002100009091700870081001109%10%70717031000090007008756910012010%11%85653041000010000700884101001200%0%0051000090007008630710010010%11%07016100009091700870081001109%10%70717071000090007008756910012010%11%85653081000090007008662310010510%11%3893385910000100007008841010012000%00Example 1: Improve the heat rate with a constant capacityExample 2: Increase the capacity with a constant Btu input (effectively improves heat rate)Example 3: Improve the heat rate and expand capacity (savings for old capacity use old heat rate for conversion, savings for new capacity convert using new heat rate)Example 4: Increased capacity, but at the same heat rate (no savings)Example 5: Gas plant with improved heat rate and constant capacityExample 6: Gas plant with increased capacity at a constant Btu inputExample 7: Gas plant with improved heat rate and increased capacity with overall increase in Btu inputExample 8: Gas plant with improved heat rate and increased capacity with overall decrease in Btu inputExample 9: Gas plant with increased capacity, but at the same heat rate (no savings)Two ways to handle savings calculations:Produce a table of conservative, but risk-free assumptions for expected heat rate improvements that should be used for specific projects. Basically GDS simulates potential projects using the general algorithm and prescribes anticipated savings. Pro: no risk and no justification required. Con: lower savings, reduced accuracy, and fewer allowed projects (limited to those projects on the prescribed table).Use actual projected heat rate improvement on a project basis. More of a defined protocol rather than a prescriptive measure. Pro: Greater savings and more accurate savings. Con: Requires reasonable confidence in utilities’ ability to model, report, and justify heat rate improvement estimates for generation projects. Will also require careful definition of baseline heat rate adjustment to account for maintenance activities.High Efficiency Transformers savings algorithm:?kWhyr=8,760×LoadPeakFLCbase2×FLLbase×LF + NLLbase-LoadPeakFLCee2×FLLee×LF + NLLee?kWPeak=LoadPeakFLCbase2×FLLbase + NLLbase-LoadPeakFLCee2×FLLee + NLLeeWhere:LoadPeak= Load during peak period (kVA)FLC= transformer rated full-load capacity (kVA)FLL= full-load losses, transformer winding kW loss at rated load (kW)LF= loss factor, ratio of average losses to peak losses (%)NLL = no-load losses (kW)8,760 = hours per year (hours)Transmission Line Reconductoring savings algorithm:?kWhyr=3×Ipeak2×Rbase-Ree×LF×8,7601,000?kWPeak=31,000×Ipeak2×Rbase-ReeWhere:Ipeak= Peak current (Amperes)R= Conductor Resistance for a three phase configuration, found in standard references like the Aluminum Electrical Conductor Handbook (Ohms)LF= loss factor, ratio of average losses to peak losses (%)3 = multiplied by 3 for each phase of 3 phase power8,760 = hours per year (hours/yr)1,000 = Watts/kilowatts (W/kW)Voltage Conversion savings algorithm:?kWhyr=LLbase-kVbasekVee2×LLbase×LF×8,760?kWPeak=LLbase-kVbasekVee2×LLbaseWhere:kVbase= Voltage of base lines (kV)kVee= Voltage of higher voltage, efficient lines (kV)LLbase= Line Loss at peak load for original, lower-voltage system (kW)LF= loss factor, ratio of average losses to peak losses (%)8,760 = hours per year (hours)Automated Conservation Voltage Reduction savings algorithm:?kWhyr=ikWhpre,i×CVRf,i×Vr,i%(1-CVRf,i×Vr,i%)Where:CVRf,i= Conservation Voltage Reduction Factor calculated for period ikWhpre,i= Energy delivered by feeder during period iVr,i %= Average voltage reduction at end of line during period ii = Defines each period of the year. For example, the year may be split into summer weekends, summer weekdays, winter weekends, winter weekdays, shoulder weekends, and shoulder weekdays. If this measure moves forward, GDS will clearly define the periods to use.CVRf will have to be modeled, measured, or prescribed for a given project. Stakeholder feedback desired as to how to best design this measure. Similar to generation measures, we can go two ways:Produce a table of conservative, but risk-free prescribed CVRf values that should be used for specific projects. Basically GDS simulates potential projects using the general algorithm and prescribes anticipated savings. Pro: no risk and no justification required. Con: lower savings, reduced accuracy, and fewer allowed project types.Use actual modeled CVRf values on a project basis. More of a defined protocol for how to model these values rather than a prescriptive measure. Pro: Greater savings and more accurate savings. Con: Requires reasonable confidence in utilities’ ability to model, report, and justify CVRf estimates for. Software modeling tools do exist. ................
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