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Chiller IPLV Calculation

I want to adjust IPLV of Chiller:Electric:EIR. I referred to Engineering Reference and calculate the IPLV in Excel before running simulation, which can avoid iterating simulation many times. When I change the coefficients of three chiller performance curves in the Excel, I can get the IPLV instantly.

image description

However, the calculated IPLV (6.62) in the Excel is approximately 1.5% larger than the reported IPLV (6.52) in the html file. I did a sizing run to output the html file.

image description

I saw this post, and I have already fix the Minimum Value of y (Entering condenser water temperature). IPLV calculating condition is within the Minimum/Maximum value of x/y.

What is causing this difference? I can't identify it. Is it due to the significant figures? Or are the numbers in Engineering Reference different from numbers actually used in EnergyPlus? I want to calculate IPLV accurately in Excel.

The excel, html file and the idf file (V9-6-0) are here. I want to calculate IPLV accurately in Excel to avoid running simulation again and again. Any suggestions would be appreciated.

Chiller IPLV Calculation

I want to adjust IPLV of Chiller:Electric:EIR. I referred to Engineering Reference and calculate the IPLV in Excel before running simulation, which can avoid iterating simulation many times. When I change the coefficients of three chiller performance curves in the Excel, I can get the IPLV instantly.

image description

However, the calculated IPLV (6.62) in the Excel is approximately 1.5% larger than the reported IPLV (6.52) in the html file. I did a sizing run to output the html file.

image description

I saw this post, and I have already fix fixed the Minimum Value of y (Entering condenser water temperature). IPLV calculating condition is within the Minimum/Maximum value of x/y.

What is causing this difference? I can't identify it. Is it due to the significant figures? Or are the numbers in Engineering Reference different from numbers actually used in EnergyPlus? I want to calculate IPLV accurately in Excel.EnergyPlus?

The excel, html file and the idf file (V9-6-0) are here. I want to calculate IPLV accurately in Excel to avoid running simulation again and again. Any suggestions would be appreciated.

Chiller IPLV Calculation

I want to adjust IPLV of Chiller:Electric:EIR. I referred to Engineering Reference and calculate the IPLV in Excel before running simulation, which can avoid iterating simulation many times. When I change the coefficients of three chiller performance curves in the Excel, I can get the IPLV instantly.

image description

However, the calculated IPLV (6.62) in the Excel is approximately 1.5% larger than the reported IPLV (6.52) in the html file. I did a sizing run to output the html file.

image description

I saw this post, and I have already fixed the Minimum Value of y (Entering condenser water temperature). IPLV calculating condition is within the Minimum/Maximum value of x/y.

Minimum Unloading Ratio of Chiller:Electric:EIR is set to 0.1 which is lower than 0.25, so I think the degradation coeffcient does not affect the IPLV calculation.

What is causing this difference? I can't identify it. Is it due to the significant figures? Or are the numbers in Engineering Reference different from numbers actually used in EnergyPlus?

The excel, html file and the idf file (V9-6-0) are here. I want to calculate IPLV accurately in Excel to avoid running simulation again and again. Any suggestions would be appreciated.

Chiller IPLV Calculation

I want to adjust IPLV of Chiller:Electric:EIR. I referred to Engineering Reference and calculate the IPLV in Excel before running simulation, which can avoid iterating simulation many times. When I change the coefficients of three chiller performance curves in the Excel, I can get the IPLV instantly.

image description

However, the calculated IPLV (6.62) in the Excel is approximately 1.5% larger than the reported IPLV (6.52) in the html file. I did a sizing run to output the html file.

image description

I saw this post, and I have already fixed the Minimum Value of y (Entering condenser water temperature). IPLV calculating condition is within the Minimum/Maximum value of x/y.

Minimum Unloading Ratio of Chiller:Electric:EIR is set to 0.1 which is lower than 0.25, so I think the degradation coeffcient coefficient does not affect the IPLV calculation.

What is causing this difference? I can't identify it. Is it due to the significant figures? Or are the numbers in Engineering Reference different from numbers actually used in EnergyPlus?

The excel, html file and the idf file (V9-6-0) are here. I want to calculate IPLV accurately in Excel to avoid running simulation again and again. Any suggestions would be appreciated.

Chiller IPLV Calculation

I want to adjust IPLV of Chiller:Electric:EIR. I referred to Engineering Reference and calculate the IPLV in Excel before running simulation, which can avoid iterating simulation many times. When I change the coefficients of three chiller performance curves in the Excel, I can get the IPLV instantly.

image description

However, the calculated IPLV (6.62) in the Excel is approximately 1.5% larger than the reported IPLV (6.52) in the html file. I did a sizing run to output the html file.

image description

I saw this post, and I have already fixed the Minimum Value of y (Entering y. IPLV calculating conditions are within the Minimum/Maximum value of x/y. (When Chiller:Electric:EIR is generated from HVACTemplate, the default Minimum Value of y for Curve:Biquadratic is 24 which is higher than the entering condenser water temperature). IPLV calculating condition is within the Minimum/Maximum value of x/y.temperature of 18.3degC at 25% load, which should be fixed.)

Minimum Unloading Ratio of Chiller:Electric:EIR is set to 0.1 which is lower than 0.25, so I think the degradation coefficient does not affect the IPLV calculation.

What is causing this difference? I can't identify it. Is it due to the significant figures? Or are the numbers in Engineering Reference different from numbers actually used in EnergyPlus?

The excel, html file and the idf file (V9-6-0) are here. I want to calculate IPLV accurately in Excel to avoid running simulation again and again. Any suggestions would be appreciated.

Chiller IPLV Calculation

I want to adjust IPLV of Chiller:Electric:EIR. I referred to Engineering Reference and calculate the IPLV in Excel before running simulation, which can avoid iterating simulation many times. When I change the coefficients of three chiller performance curves in the Excel, I can get the IPLV instantly.

image description

However, the calculated IPLV (6.62) in the Excel is approximately 1.5% larger than the reported IPLV (6.52) in the html file. I did a sizing run to output the html file.

image description

I saw this post, and I have already fixed the Minimum Value of y. IPLV calculating conditions are within the Minimum/Maximum value of x/y. (When Chiller:Electric:EIR is generated from HVACTemplate, the default Minimum Value of y for Curve:Biquadratic is 24 which is higher than the entering condenser water temperature of 18.3degC at 25% load, which should be fixed.)

Minimum Unloading Ratio of Chiller:Electric:EIR is set to 0.1 which is lower than 0.25, so I think the degradation coefficient does not affect the IPLV calculation.

What is causing this difference? I can't identify it. Is it due to the significant figures? Or are the numbers in Engineering Reference different from numbers actually used in EnergyPlus?

The excel, html file and the idf file (V9-6-0) are here. I want to calculate IPLV accurately in Excel to avoid running simulation again and again. Any suggestions would be appreciated.

Chiller IPLV Calculation

I want to adjust IPLV of Chiller:Electric:EIR. I referred to Engineering Reference and calculate the IPLV in Excel before running simulation, which can avoid iterating simulation many times. When I change the coefficients of three chiller performance curves in the Excel, I can get the IPLV instantly.

image description

However, the calculated IPLV (6.62) in the Excel is approximately 1.5% larger than the reported IPLV (6.52) in the html file. I did a sizing run to output the html file.

image description

I saw this post, and I have already fixed the Minimum Value of y. IPLV calculating conditions are within the Minimum/Maximum value of x/y. (When Chiller:Electric:EIR is generated from HVACTemplate, the default Minimum Value of y for Curve:Biquadratic is 24 which is higher than the entering condenser water temperature of 18.3degC at 25% load, which should be fixed.)

Minimum Unloading Ratio of Chiller:Electric:EIR is set to 0.1 which is lower than 0.25, so I think the degradation coefficient does not affect the IPLV calculation.

What is causing this difference? I can't identify it. Is it due to the significant figures? Or are the numbers in Engineering Reference different from numbers actually used in EnergyPlus?

The excel, html file and the idf file (V9-6-0) are here. I want to calculate IPLV accurately in Excel to avoid running simulation again and again. Any suggestions would be appreciated.