3.4.8 Process, Gas

Commercial gas equipment includes the following:

  • Ovens
  • Fryers
  • Grills
  • Other equipment

The majority of gas equipment is located in the space and may contribute both sensible and latent heat. Gas equipment is typically modeled by specifying the rate of peak gas consumption and modifying this with a fractional schedule. Energy consumption data for gas equipment is only beginning to emerge.

Because of these limits, the COMNET procedure for commercial gas is limited. The procedure consists of prescribed power and energy values for use with both the proposed design and the baseline building. No credit for commercial gas energy efficiency features is offered.

The prescribed values are provided in Appendix B.1 Schedules are defaulted to be continuous operation.

Gas Equipment Power

Applicability

All buildings that have gas appliances or commercial gas equipment

Definition

Commercial gas power is the average power for all commercial gas equipment, assuming constant year-round operation.

Units

Btu/h-ft²

Input Restrictions (except residential)

The values in Appendix B are prescribed. 

Input Restrictions (residential)

Annual gas use for cooking and clothes drying, shall be calculated as shown below:

(Equation 3.4.8-1)

$$\begin{align} Therms = & NmbrDU_{du,cook} \cdot 45 + \\ & NmbrDU_{du,dry} \cdot 26.5 + NmbrBR_{du,dry} \cdot 8.8 + \\ & NmbrComDry \cdot 64.2 + NmbrBR_{com,dry} \cdot 21.3 \end{align}$$

where

Therms                annual gas use (therms/y)

NmbrDUdu,cook    number of dwelling units with gas cooking

NmbrDUdu,dry      number of dwelling units with in-unit gas clothes drying

NmbrBRdu,dry      number of bedrooms in dwelling units units with in-unit gas clothes drying

NmbrComDry      number of dryers in common areas (serving multiple dwelling units)

NmbrBRcom,dry    number of bedrooms served by common dryers (serving multiple dwelling units)

Once the annual therms are determined using equation 3.4.8-1, the annual energy is converted to power by dividing by the full-time equivalent hours of operation in the residential schedule. If the power is to be expressed per floor area, then another adjustment to the value is required. 

(Equation 3.4.8-2)

$$ GasPower = \frac{Therms}{100 \cdot FTEhours} $$

where

GasPower          rate of gas use in kBtu/h

FTEhours           full -time equivalent hours in the schedule for gas use. If the residential receptacle schedule is used, the FTE hours are 5,840

100                     conversion factor to change therms to kBtu

Baseline Rules

Same as the proposed design

 

Table 3.4.8-1: Annual Residential Gas Use for Cooking and Clothes Drying 

Source:  Energy Star Multi-Family Highrise Simulation Guidelines, Version 1.0, Revision 03, January 2015, pages 23-35.

 

Annual Energy Use

Load Fraction

 

Per Unit

Per BR

Per Area

Sensible

Latent

Gas in Dwelling Unit (therms/y)

       

Cooking

45

0

0

0.40

0.30

Clothes dryer

26.5

8.8

0

0.10

0.05

           

Gas in Common Laundry Space (therms/y)

 

 

 

Clothes dryer

64.2

21.3

0

0.10

0.05

Gas Equipment Schedule

Applicability

All buildings that have commercial gas equipment

Definition

The schedule of operation for commercial gas equipment. This is used to convert gas power to energy use.

Units

Data structure: schedule, fractional

Input Restrictions

Continuous operation is prescribed. The default values for power are based on continuous operation, although this is not realistic.

Baseline Rules

Same as the proposed design

 

Gas Equipment Location

Applicability

All buildings that have commercial gas equipment

Definition

The assumed location of the gas equipment for modeling purposes. Choices are in the space or external.

Units

List (see above)

Input Restrictions

As designed.

Baseline Rules

Same as the proposed design

 

Radiation Factor

Applicability

Gas appliances located in the space

Definition

The fraction of heat gain to appliance energy use

Units

Fraction

Input Restrictions

Default value is 0.15. Other values can be used when a detailed inventory of equipment is known. The override value shall be based on data in Table 5C, Chapter 18, ASHRAE HOF, 2009, or similar tested information from the manufacturer.

Baseline Rules

Same as the proposed design

 

 

  • 1. See Table C-43, p. 146 of NREL/TP-550-41956, Methodology for Modeling Building Energy Performance across the Commercial Sector, Technical Report, Appendix C, March 2008. The values in this report were taken from Table 8-3 of the California Commercial End-Use Survey, Consultants Report, March 2006, CEC-400-2006-005
Building EQ

Commercial gas equipment includes the following:

  • Ovens
  • Fryers
  • Grills
  • Other equipment

The majority of gas equipment is located in the space and may contribute both sensible and latent heat. Gas equipment is typically modeled by specifying the rate of peak gas consumption and modifying this with a fractional schedule. Energy consumption data for gas equipment is only beginning to emerge.

Because of these limits, the COMNET procedure for commercial gas is limited. The procedure consists of prescribed power and energy values for use with both the proposed design and the baseline building. No credit for commercial gas energy efficiency features is offered.

The prescribed values are provided in Appendix B.1 Schedules are defaulted to be continuous operation.

Gas Equipment Power

Applicability

All buildings that have gas appliances or commercial gas equipment

Definition

Commercial gas power is the average power for all commercial gas equipment, assuming constant year-round operation.

Units

Btu/h-ft²

Input Restrictions (except residential)

The values in Appendix B are prescribed. 

Input Restrictions (residential)

Annual gas use for cooking and clothes drying, shall be calculated as shown below:

(Equation 3.4.8-1)

$$\begin{align} Therms = & NmbrDU_{du,cook} \cdot 45 + \\ & NmbrDU_{du,dry} \cdot 26.5 + NmbrBR_{du,dry} \cdot 8.8 + \\ & NmbrComDry \cdot 64.2 + NmbrBR_{com,dry} \cdot 21.3 \end{align}$$

where

Therms                annual gas use (therms/y)

NmbrDUdu,cook    number of dwelling units with gas cooking

NmbrDUdu,dry      number of dwelling units with in-unit gas clothes drying

NmbrBRdu,dry      number of bedrooms in dwelling units units with in-unit gas clothes drying

NmbrComDry      number of dryers in common areas (serving multiple dwelling units)

NmbrBRcom,dry    number of bedrooms served by common dryers (serving multiple dwelling units)

Once the annual therms are determined using equation 3.4.8-1, the annual energy is converted to power by dividing by the full-time equivalent hours of operation in the residential schedule. If the power is to be expressed per floor area, then another adjustment to the value is required. 

(Equation 3.4.8-2)

$$ GasPower = \frac{Therms}{100 \cdot FTEhours} $$

where

GasPower          rate of gas use in kBtu/h

FTEhours           full -time equivalent hours in the schedule for gas use. If the residential receptacle schedule is used, the FTE hours are 5,840

100                     conversion factor to change therms to kBtu

Baseline Rules

There is no baseline building.

 

Table 3.4.8-1: Annual Residential Gas Use for Cooking and Clothes Drying 

Source:  Energy Star Multi-Family Highrise Simulation Guidelines, Version 1.0, Revision 03, January 2015, pages 23-35.

 

Annual Energy Use

Load Fraction

 

Per Unit

Per BR

Per Area

Sensible

Latent

Gas in Dwelling Unit (therms/y)

       

Cooking

45

0

0

0.40

0.30

Clothes dryer

26.5

8.8

0

0.10

0.05

           

Gas in Common Laundry Space (therms/y)

 

 

 

Clothes dryer

64.2

21.3

0

0.10

0.05

Gas Equipment Schedule

Applicability

All buildings that have commercial gas equipment

Definition

The schedule of operation for commercial gas equipment. This is used to convert gas power to energy use.

Units

Data structure: schedule, fractional

Input Restrictions

Continuous operation is prescribed. The default values for power are based on continuous operation, although this is not realistic.

Baseline Rules

There is no baseline building.

 

Gas Equipment Location

Applicability

All buildings that have commercial gas equipment

Definition

The assumed location of the gas equipment for modeling purposes. Choices are in the space or external.

Units

List (see above)

Input Restrictions

As designed.

Baseline Rules

There is no baseline building.

 

Radiation Factor

Applicability

Gas appliances located in the space

Definition

The fraction of heat gain to appliance energy use

Units

Fraction

Input Restrictions

Default value is 0.15. Other values can be used when a detailed inventory of equipment is known. The override value shall be based on data in Table 5C, Chapter 18, ASHRAE HOF, 2009, or similar tested information from the manufacturer.

Baseline Rules

There is no baseline building.

 
  • 1. See Table C-43, p. 146 of NREL/TP-550-41956, Methodology for Modeling Building Energy Performance across the Commercial Sector, Technical Report, Appendix C, March 2008. The values in this report were taken from Table 8-3 of the California Commercial End-Use Survey, Consultants Report, March 2006, CEC-400-2006-005
Energy Star

Commercial gas equipment includes the following:

  • Ovens
  • Fryers
  • Grills
  • Other equipment

The majority of gas equipment is located in the space and may contribute both sensible and latent heat. Gas equipment is typically modeled by specifying the rate of peak gas consumption and modifying this with a fractional schedule. Energy consumption data for gas equipment is only beginning to emerge.

Because of these limits, the COMNET procedure for commercial gas is limited. The procedure consists of prescribed power and energy values for use with both the proposed design and the baseline building. No credit for commercial gas energy efficiency features is offered.

The prescribed values are provided in Appendix B.1 Schedules are defaulted to be continuous operation.

Gas Equipment Power

Applicability

All buildings that have gas appliances or commercial gas equipment

Definition

Commercial gas power is the average power for all commercial gas equipment, assuming constant year-round operation.

Units

Btu/h-ft²

Input Restrictions (except residential)

The values in Appendix B are prescribed. 

Input Restrictions (residential)

Annual gas use for cooking and clothes drying, shall be calculated as shown below:

(Equation 3.4.8-1)

$$\begin{align} Therms = & NmbrDU_{du,cook} \cdot 45 + \\ & NmbrDU_{du,dry} \cdot 26.5 + NmbrBR_{du,dry} \cdot 8.8 + \\ & NmbrComDry \cdot 64.2 + NmbrBR_{com,dry} \cdot 21.3 \end{align}$$

where

Therms                annual gas use (therms/y)

NmbrDUdu,cook    number of dwelling units with gas cooking

NmbrDUdu,dry      number of dwelling units with in-unit gas clothes drying

NmbrBRdu,dry      number of bedrooms in dwelling units units with in-unit gas clothes drying

NmbrComDry      number of dryers in common areas (serving multiple dwelling units)

NmbrBRcom,dry    number of bedrooms served by common dryers (serving multiple dwelling units)

Once the annual therms are determined using equation 3.4.8-1, the annual energy is converted to power by dividing by the full-time equivalent hours of operation in the residential schedule. If the power is to be expressed per floor area, then another adjustment to the value is required. 

(Equation 3.4.8-2)

$$ GasPower = \frac{Therms}{100 \cdot FTEhours} $$

where

GasPower          rate of gas use in kBtu/h

FTEhours           full -time equivalent hours in the schedule for gas use. If the residential receptacle schedule is used, the FTE hours are 5,840

100                     conversion factor to change therms to kBtu

Baseline Rules

There is no baseline building.

 

Table 3.4.8-1: Annual Residential Gas Use for Cooking and Clothes Drying 

Source:  Energy Star Multi-Family Highrise Simulation Guidelines, Version 1.0, Revision 03, January 2015, pages 23-35.

 

Annual Energy Use

Load Fraction

 

Per Unit

Per BR

Per Area

Sensible

Latent

Gas in Dwelling Unit (therms/y)

       

Cooking

45

0

0

0.40

0.30

Clothes dryer

26.5

8.8

0

0.10

0.05

           

Gas in Common Laundry Space (therms/y)

 

 

 

Clothes dryer

64.2

21.3

0

0.10

0.05

Gas Equipment Schedule

Applicability

All buildings that have commercial gas equipment

Definition

The schedule of operation for commercial gas equipment. This is used to convert gas power to energy use.

Units

Data structure: schedule, fractional

Input Restrictions

Continuous operation is prescribed. The default values for power are based on continuous operation, although this is not realistic.

Baseline Rules

There is no baseline building.

 

Gas Equipment Location

Applicability

All buildings that have commercial gas equipment

Definition

The assumed location of the gas equipment for modeling purposes. Choices are in the space or external.

Units

List (see above)

Input Restrictions

As designed.

Baseline Rules

There is no baseline building.

 

Radiation Factor

Applicability

Gas appliances located in the space

Definition

The fraction of heat gain to appliance energy use

Units

Fraction

Input Restrictions

Default value is 0.15. Other values can be used when a detailed inventory of equipment is known. The override value shall be based on data in Table 5C, Chapter 18, ASHRAE HOF, 2009, or similar tested information from the manufacturer.

Baseline Rules

There is no baseline building.

  • 1. See Table C-43, p. 146 of NREL/TP-550-41956, Methodology for Modeling Building Energy Performance across the Commercial Sector, Technical Report, Appendix C, March 2008. The values in this report were taken from Table 8-3 of the California Commercial End-Use Survey, Consultants Report, March 2006, CEC-400-2006-005