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ACT: Upgrade Analysis

For California buildings, EnergyIQ offers the capability to do an "upgrade analysis" to examine the impact of implementing a select group of 35 distinct energy efficiency measures across 10 end uses, with a total of 132 efficiency levels. The methodology uses the same subset of Commercial End Use Survey (CEUS) buildings that match the user's peer group, and then presents the range of savings for those peer buildings based on the implementation of those measures on the eQUEST models for the underlying peer group.  Itron's DrCEUS Energy Efficiency Measure Analysis (EEMA) module was used to perform the measure runs -- the result is over 65,000 measure-building combinations.  

Savings ranges include three values: lower 25%-ile, median, and upper 75%-ile. Savings are expressed as a percentage of whole-building energy use for the metrics site energy, source energy, cost, and carbon emissions. Thus, the percentages are typically in the low single-digits for each highly-specific measure.  Users can choose to view savings for total energy or for gas and electricity individually.

A qualitative indicator of return on investment (ROI) is also provided.  These are based strictly on likely cost-effectiveness, without reference for the level of savings.

Because an ensemble of simulation models is not available for the national dataset (CBECS), we only provide a list of applicable measures (based on features), but not quantitative indications of savings.

The attachment titled "EIQ_MeasNames.xlsx" is a compact list of all the available energy efficiency actions that EnergyIQ can offer.  The measures are, by definition, only applied to those buildings for which they are applicable (e.g., CFL lighting only to those buildings using incandescent lighting).  Note that when looking at whole-building metrics, HVAC interactions are included.  In heating climates, this will dilute savings from lighting and plug loads.

The logic used to determine which measures are applicable to a user's building is detailed in the attached file name "EEMs Logic." The first tab, User Input, is the acceptable responses to the My Buildings features. Each response has an ID. The rest of the tabs are end use specific measure qualifications. The user data provided in the Features GUI must meet certain criteria in order to qualify for a specific EEM, as it is detailed in this document. Criteria is described using the response IDs.

A detailed description of each measure is provided via tooltips in the online GUI.  

Analysis Method and Overview

The measures incorporated into the Upgrade Analysis were limited to those that were already available from the DrCEUS EEMA module.


Basic Measure Organization

The first tab of this file (EIQ_MeasNames.xlsx) presents a summary of the measures and the parameters used for each measure run.  These are the descriptions that are used in the EnergyIQ tooltips.  The fields in this table are:

End Use Measure Group is a high-level grouping of the measures.  Examples are (building) Envelope, Outdoor Lighting, and Packaged HVAC.

Measure Category is a secondary, lower-level grouping of the measures corresponding to a specific technology (CFLs, linear fluorescents, etc) or configuration (package, split-system, etc.)

Measure Name is a description of the actual measure as implemented.  Each of these measures will have a high-efficiency value (EE-Value field) or configuration, and some also have a baseline efficiency value (Base-Value field) and a corresponding description of the basis for these efficiencies (ValueBasis field).


Measure Groupings

There are 10 End Use Measure Groups, each encompassing a different number of detailed measures.  The EU measure groups are:

Envelope includes several roof measures, wall insulation, and window measures.

Outdoor Lighting includes photocell control, CFLs, and T12-to-T8 linear fluorescent conversion measures.

Indoor Lighting includes CFLs, and T12-to-T8 linear fluorescent conversion measures, as well as a high-level, overall reduction in the total lighting power density (LPD).

Service Hot Water includes high-efficiency storage water heater and boiler options, storage tank insulation, and pipe insulation.

Refrigeration measures are primarily those applicable to remote/rack types systems.  As such, these measures all apply to the rack system (i.e. compressor, condenser, subcooling, controls), and it does not include and display case measures.

Packaged HVAC contains by far the most individual measures and covers most unitary HVAC systems, as well as economizers for those systems.  For the measure analysis, cooling and heating efficiencies are actually separate measures [these might be post-processed and combined though].  The packaged HVAC systems represented are packaged and split-system single-zone systems (SZ) cooling, air source heat pumps (ASHP), water loop heat pumps (WLHP) packaged terminal heat pumps (PTHP), and gas furnaces (GF).  For the units with cooling and electric/HP heating, three levels of cooling efficiency were analyzed: Above Standard (AboveStd), Better Efficiency (BetterEff), and Best Efficiency (BestEff).  These names are encoded into the measure names rather than the actual efficiency values, but the efficiency values are available.  For gas heating, three levels of efficiency were also simulated, but the actual % value is used in the measure name.  Other notes about these measures are listed below:

For the SZ & ASHP cooling units, two size categories were used for consistency with codes & standards minimum efficiencies: <5.42 tons (SEER rated equipment) and >=5.42 tons (EER rated equipment).

For the WLHP and PTHP units, only the efficiency was varied, though technically PTHP minimum efficiencies vary by unit capacity.

The data used to set the three efficiency levels for all HVAC equipment including chillers, is contained in the file attached below: EquipmentEfficiencyReferences.xlsx. 

Built-up HVAC does not include high-efficiency systems, but rather conversion to or modifications of these systems.  The measures include converting a constant-volume systems to a VAV system, reducing VAV system minimum airflow %, changing electric to gas reheat, and adding an enthalpy econmizer.

HVAC Chillers has the second most numerous measures, due to the large number of chiller type/condenser type combinations.  The primary measures are high-efficiency chillers, but chilled water reset is also included.  Centrifugal, reciprocating, screw, and scroll chillers in water-cooled or air-cooled options are are all available.  As for the packaged HVAC systems, three levels of efficiency were modeled for each chiller/condenser configuration.  Note that size (ton) categories were not used for these measures for simplicity (though these are used for efficiency standards), and because in practice, each chiller/condenser configuration is usually applied for a specific cooling load size range.  For example, reciprocating air-cooled chillers might typically be used for smaller applications, while centrifugal water-cooled chillers would be used for larger applications.

HVAC Boilers includes high-efficiency hot water and steam boilers.  Three levels of efficiency were also modeled for these measures.

HVAC Motors include premium efficiency motors for HVAC hot/cold water circulation pumps and ventilation fans, as well as VSD or two-speed control for pumps.
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Unknown user,
Jun 5, 2013, 3:35 PM
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Evan Mills,
Jan 9, 2012, 12:10 PM
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Bob Ramirez,
Sep 30, 2011, 2:41 PM
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