|
System Name |
|
|---|---|
|
Applicability |
All cogeneration systems |
|
Definition |
A unique identifier that makes a link to the construction documents |
|
Units |
Text, unique |
|
Input Restrictions |
None |
|
Baseline Rules |
Not applicable |
|
Rated Output |
|
|---|---|
|
Applicability |
All cogeneration systems |
|
Definition |
The rated electric power that the cogenerator can produce |
|
Units |
Kilowatts (kW) |
|
Input Restrictions |
None |
|
Baseline Rules |
Not applicable |
|
Rated Efficiency |
|
|---|---|
|
Applicability |
All cogeneration systems |
|
Definition |
The efficiency of converting a fuel to electricity |
|
Units |
Unitless |
|
Input Restrictions |
None |
|
Baseline Rules |
Not applicable |
|
Heat Production Rate |
|
|---|---|
|
Applicability |
All cogeneration systems |
|
Definition |
The rate of heat production at the rated output |
|
Units |
Btu/h |
|
Input Restrictions |
None |
|
Baseline Rules |
Not applicable |
|
Heat Temperature |
|
|---|---|
|
Applicability |
All cogeneration systems |
|
Definition |
The temperature of the water produced |
|
Units |
Degrees Fahrenheit (°F) |
|
Input Restrictions |
None |
|
Baseline Rules |
Not applicable |
|
Modulation |
|
|---|---|
|
Applicability |
All cogeneration systems |
|
Definition |
The capability of the cogeneration system to modulate output with corresponding modulation of input energy and waste heat |
|
Units |
Data structure |
|
Input Restrictions |
None |
|
Baseline Rules |
Not applicable |
|
Schedule |
|
|---|---|
|
Applicability |
All cogeneration systems |
|
Definition |
A schedule that indicates when the cogeneration system will operate and perhaps at what capacity (if there is a means for modulation) |
|
Units |
Data structure: schedule, on/off or fractional |
|
Input Restrictions |
None |
|
Baseline Rules |
Not applicable |
Candidate buildings may have combined heat and power (CHP) cogeneration systems and the energy generated by these systems may offset the power used by HVAC, lighting, and other building systems. Since most CHP systems work under a metering arrangement whereby the building electrical or thermal loads act as a control of the system, the simulation of CHP systems needs to be on the same timestep as the whole building energy simulation so that it can be aligned with the building loads and the utility rate structure.
This section describes one set of building descriptors for specifying a CHP system. This set of building descriptors is based on the DOE 2.2 electric generator with heat recovery scheme. Other models may be used for CHP systems. The heat recovery inputs apply only to the proposed design, as the baseline building is modeled as an electrical generator only without recovered heat.
3.10.3.1 Configuration
This set of building descriptors addresses the overall design of the CHP system, including the type, control, capacity, efficiency and heat recovery possibilities.
| CHP System Name | |
|---|---|
| Applicability | All CHP systems |
| Definition | A unique identifier that can be used to reference the CHP system and associate it with the construction documents. This is typically listed as an electric generator with or without heat recovery. |
| Units | Text, Unique |
| Input Restrictions | As designed |
| Baseline Building | Same as Proposed |
| CHP System Type | |
|---|---|
| Applicability | All CHP systems |
| Definition | This building descriptor includes information needed to determine the criteria from baseline standards. The choices are typically Engine Generator, Gas Turbine Generaotor and Steam Turbine Generator. |
| Units | Text, Unique |
| Input Restrictions | Engine Generator, Gas Turbine Generaotor and Steam Turbine Generator |
| Baseline Building | Same as Proposed |
| CHP Equipment Capacity | |
|---|---|
| Applicability | All CHP systems |
| Definition | This building descriptor includes the nominal full load capacity of the electrical generator portion of the CHP plant expressed in kW. This may be expressed as a range or in separate minimum and maximum ratios |
| Units | Unitless ratio |
| Input Restrictions | As Designed (minimum must be > 0) |
| Baseline Building | Same as Proposed |
| CHP Track Mode | |
|---|---|
| Applicability | All CHP systems |
| Definition | This building descriptor describes how the cogeneration equipment attached to this meter is to be controlled. This is typically achieved by tracking an electric load of a particular electric meter or a thermal load of the loop to which the waste heat is being rejected or a combination thereof. |
| Units |
Keyword / Code Word The code-word applies to this keyword, and the number in parenthesis the flag value that is equivalent to the code-word when the COGEN-TRACK-SCH is used: DONT-RUN (0) Specifies that the generators are shut off. This mode of operation allows a COGEN-TRACK-SCH to shut off the generators during certain times of the day or year. TRACK-ELEC (1) Specifies that the generators are to track the meter's electrical load. This mode works only for UTILITY electric meters, as ELECTRIC-SALE meters do not have any demands that can be tracked. TRACK-THERMAL (2) Specifies that the generators are to track the thermal load of an attached loop. For this mode to work, each attached generator must also be attached to a hot water loop. Note that, while multiple generators may be on the same electric meter, each of these generators may be attached to the same or different hot water loops, and may therefore be tracking the same or different thermal loads when operating in this mode. · When using this mode with a UTILITY meter, it is possible that the generators might produce more electricity than this meter demands. In this case, you should also attach each generator to a meter of type electric sale (via the generator's surplus-sale keyword); otherwise the surplus power will be lost. · When using this mode with an electric-sale meter (as the electric-meter, not the surplus-meter), all power will be sold. The amount generated and sold will then be a function of the thermal demands. TRACK-LESSER (3) Specifies that each generator is to track the smaller of this meter's electric demand, and the thermal demand of the generator's attached hot water loop. This mode works only when the generators are also attached to hot water loop TRACK-GREATER (4) Specifies that each generator is to track the greater of this meter's electric demand, and the thermal demand of the generator's attached hot water loop. This mode works only when the generators are also attached to a hot water loop. · When using this mode, it is possible that the generators might produce more electricity than this meter demands. In this case, you should also attach each generator to a meter of type electric-sale (via the generator's surplus-sale keyword); otherwise the surplus power will be lost. MAX-OUTPUT (5) Specifies that the generators are to run at maximum output. When using this mode with a utility meter, it is possible that the generators might produce more electricity than this meter demands. In this case, you should also attach each generator to a meter of type electric-sale (via the generator's surplus-sale keyword); otherwise the surplus power will be lost.
|
| Input Restrictions | As Designed per keywords or code words |
| Baseline Building | No heat recovery is to be modeled in the baseline design so the electrical genewrator CHP system shall be set to track electric loads only (TRACK-ELEC (1)) |
| CHP Track Schedule | |
|---|---|
| Applicability | All CHP systems |
| Definition | This building descriptor when specified, will override any value given for COGEN-TRACK-MODE. This keyword allows the operational mode of generators to shift according to the time of day or year. |
| Units | 8760 Scheule of type = Flag. Acceptable flag values are 0, 1, 2, 3, 4, and 5, and have the meaning as described for CHP Track Mode. |
| Input Restrictions | As Designed (minimum must be > 0) |
| Baseline Building | No heat recovery is to be modeled in the baseline design so the electrical genewrator CHP system shall be set to track electric loads only (TRACK-ELEC (1)) for all hours that the generator is available to run per the proposed operating schedule. |
| CHP Performance Range | |
|---|---|
| Applicability | All CHP systems |
| Definition | This building descriptor includes the operational range as a decimal relative to the CHP equipment capacity |
| Units | Text, Unique |
| Input Restrictions | As Designed |
| Baseline Building | Same As Proposed |
| CHP Equipment Capacity | |
|---|---|
| Applicability | All CHP systems |
| Definition | This building descriptor specifies the ratio of design fuel consumption to design electrical output, when both are in the same units. Note that for DOE 2.2 this entry is in terms of the higher heating value of the fuel and should be verified based upon the simulation protocol utilized. |
| Units | Unitless ratio |
| Input Restrictions | As Designed (must be > 0) |
| Baseline Building | Same As Proposed |
| CHP Heat Recovery Loop | |
|---|---|
| Applicability | All CHP systems |
| Definition | This building descriptor specifies the loop to which this generator will recover exhaust heat |
| Units | Text, Unique |
| Input Restrictions | As Designed (must be > 0) |
| Baseline Building | None – no heat is to be recovered in the baseline building |
| CHP Heat Recovery Performance Curve | |
|---|---|
| Applicability | All CHP systems |
| Definition | This building descriptor specifies the efficiency of the cogeneration equipment to recover heat as a function of the instantaneous performance (expressed as part load ratio) Specifically this descriptor specifies the variation in full-load recoverable exhaust heat with part load ratio. The factor is set as a curve and must be normalized to 1.0 at a part load ratio of 1.0. |
| Units | Percent (%) |
| Input Restrictions | As Designed - Quadric Curve with Input Coefficients (Z = a + bX + cX2) |
| Baseline Building | Default Coefficients a = 0.29562601, b = 0.4930194, c = 0.21135481 |
| System Name | |
| Applicability | All cogeneration systems |
|---|---|
| Definition | A unique identifier that makes a link to the construction documents |
| Units | Text, unique |
| Input Restrictions | None |
| Rated Output | |
| Applicability | All cogeneration systems |
|---|---|
| Definition | The rated electric power that the cogenerator can produce |
| Units | Kilowatts (kW) |
| Input Restrictions | None |
| Rated Efficiency | |
| Applicability | All cogeneration systems |
|---|---|
| Definition | The efficiency of converting a fuel to electricity |
| Units | Unitless |
| Input Restrictions | None |
| Heat Production Rate | |
| Applicability | All cogeneration systems |
|---|---|
| Definition | The rate of heat production at the rated output |
| Units | Btu/h |
| Input Restrictions | None |
| Heat Temperature | |
| Applicability | All cogeneration systems |
|---|---|
| Definition | The temperature of the water produced |
| Units | Degrees Fahrenheit (°F) |
| Input Restrictions | None |
| Modulation | |
| Applicability | All cogeneration systems |
|---|---|
| Definition | The capability of the cogeneration system to modulate output with corresponding modulation of input energy and waste heat |
| Units | Data structure |
| Input Restrictions | None |
| Schedule | |
| Applicability | All cogeneration systems |
|---|---|
| Definition | A schedule that indicates when the cogeneration system will operate and perhaps at what capacity (if there is a means for modulation) |
| Units | Data structure: schedule, on/off or fractional |
| Input Restrictions | None |
| System Name | |
| Applicability | All cogeneration systems |
|---|---|
| Definition | A unique identifier that makes a link to the construction documents |
| Units | Text, unique |
| Input Restrictions | None |
| Rated Output | |
| Applicability | All cogeneration systems |
|---|---|
| Definition | The rated electric power that the cogenerator can produce |
| Units | Kilowatts (kW) |
| Input Restrictions | None |
| Rated Efficiency | |
| Applicability | All cogeneration systems |
|---|---|
| Definition | The efficiency of converting a fuel to electricity |
| Units | Unitless |
| Input Restrictions | None |
| Heat Production Rate | |
| Applicability | All cogeneration systems |
|---|---|
| Definition | The rate of heat production at the rated output |
| Units | Btu/h |
| Input Restrictions | None |
| Heat Temperature | |
| Applicability | All cogeneration systems |
|---|---|
| Definition | The temperature of the water produced |
| Units | Degrees Fahrenheit (°F) |
| Input Restrictions | None |
| Modulation | |
| Applicability | All cogeneration systems |
|---|---|
| Definition | The capability of the cogeneration system to modulate output with corresponding modulation of input energy and waste heat |
| Units | Data structure |
| Input Restrictions | None |
| Schedule | |
| Applicability | All cogeneration systems |
|---|---|
| Definition | A schedule that indicates when the cogeneration system will operate and perhaps at what capacity (if there is a means for modulation) |
| Units | Data structure: schedule, on/off or fractional |
| Input Restrictions | None |