economizer implementation changes

lib/openstudio-standards.rb

@@ -497,7 +497,6 @@ module OpenstudioStandards
   require_relative "#{proto}/ashrae_90_1/nrel_nze_ready_2017/nrel_zne_ready_2017.FanOnOff"
   require_relative "#{proto}/ashrae_90_1/nrel_nze_ready_2017/nrel_zne_ready_2017.FanVariableVolume"
   require_relative "#{proto}/ashrae_90_1/nrel_nze_ready_2017/nrel_zne_ready_2017.HeatExchangerAirToAirSensibleAndLatent"
-  require_relative "#{proto}/ashrae_90_1/nrel_nze_ready_2017/nrel_zne_ready_2017.Model"
   require_relative "#{proto}/ashrae_90_1/nrel_nze_ready_2017/nrel_zne_ready_2017.Model.elevators"
   require_relative "#{proto}/ashrae_90_1/nrel_nze_ready_2017/nrel_zne_ready_2017.hvac_systems"
   # ZE AEDG Multifamily

lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2016/ashrae_90_1_2016.Model.rb

@@ -1,38 +1,6 @@
 class ASHRAE9012016 < ASHRAE901
   # @!group Model
 
-  # Determine the prototypical economizer type for the model.
-  #
-  # @param model [OpenStudio::Model::Model] OpenStudio model object
-  # @param climate_zone [String] ASHRAE climate zone, e.g. 'ASHRAE 169-2013-4A'
-  # @return [String] the economizer type.  Possible values are:
-  #   'NoEconomizer'
-  #   'FixedDryBulb'
-  #   'FixedEnthalpy'
-  #   'DifferentialDryBulb'
-  #   'DifferentialEnthalpy'
-  #   'FixedDewPointAndDryBulb'
-  #   'ElectronicEnthalpy'
-  #   'DifferentialDryBulbAndEnthalpy'
-  def model_economizer_type(model, climate_zone)
-    economizer_type = case climate_zone
-                      when 'ASHRAE 169-2006-0A',
-                          'ASHRAE 169-2006-1A',
-                          'ASHRAE 169-2006-2A',
-                          'ASHRAE 169-2006-3A',
-                          'ASHRAE 169-2006-4A',
-                          'ASHRAE 169-2013-0A',
-                          'ASHRAE 169-2013-1A',
-                          'ASHRAE 169-2013-2A',
-                          'ASHRAE 169-2013-3A',
-                          'ASHRAE 169-2013-4A'
-                        'DifferentialEnthalpy'
-                      else
-                        'DifferentialDryBulb'
-                      end
-    return economizer_type
-  end
-
   # Adjust model to comply with fenestration orientation requirements
   # @note code_sections [90.1-2013_5.5.4.5]
   #
@@ -299,7 +267,7 @@ def model_add_lights_shutoff(model)
       end
 
       # guard clause to skip space with no lights
-      next if space_lights.empty? 
+      next if space_lights.empty?
 
       # if lights are defined at the space type level, clone each lights object and make it individual to the space
       new_space_lights = []

lib/openstudio-standards/prototypes/ashrae_90_1/ashrae_90_1_2019/ashrae_90_1_2019.Model.rb

@@ -1,38 +1,6 @@
 class ASHRAE9012019 < ASHRAE901
   # @!group Model
 
-  # Determine the prototypical economizer type for the model.
-  #
-  # @param model [OpenStudio::Model::Model] OpenStudio model object
-  # @param climate_zone [String] ASHRAE climate zone, e.g. 'ASHRAE 169-2013-4A'
-  # @return [String] the economizer type.  Possible values are:
-  #   'NoEconomizer'
-  #   'FixedDryBulb'
-  #   'FixedEnthalpy'
-  #   'DifferentialDryBulb'
-  #   'DifferentialEnthalpy'
-  #   'FixedDewPointAndDryBulb'
-  #   'ElectronicEnthalpy'
-  #   'DifferentialDryBulbAndEnthalpy'
-  def model_economizer_type(model, climate_zone)
-    economizer_type = case climate_zone
-                      when 'ASHRAE 169-2006-0A',
-                          'ASHRAE 169-2006-1A',
-                          'ASHRAE 169-2006-2A',
-                          'ASHRAE 169-2006-3A',
-                          'ASHRAE 169-2006-4A',
-                          'ASHRAE 169-2013-0A',
-                          'ASHRAE 169-2013-1A',
-                          'ASHRAE 169-2013-2A',
-                          'ASHRAE 169-2013-3A',
-                          'ASHRAE 169-2013-4A'
-                        'DifferentialEnthalpy'
-                      else
-                        'DifferentialDryBulb'
-                      end
-    return economizer_type
-  end
-
   # Adjust model to comply with fenestration orientation requirements
   # @note code_sections [90.1-2013_5.5.4.5]
   #
@@ -299,7 +267,7 @@ def model_add_lights_shutoff(model)
       end
 
       # guard clause to skip space with no lights
-      next if space_lights.empty? 
+      next if space_lights.empty?
 
       # if lights are defined at the space type level, clone each lights object and make it individual to the space
       new_space_lights = []

lib/openstudio-standards/prototypes/common/objects/Prototype.Model.rb

@@ -2474,7 +2474,13 @@ def model_multiply_schedule(model, day_sch, multiplier, limit)
   # end reduce schedule
 
   # Determine the prototypical economizer type for the model.
-  # Defaults to the pre-90.1-2010 assumption of DifferentialDryBulb.
+  # Defaults to FixedDryBulb based on anecdotal evidence of this being
+  # the most common type encountered in the field, combined
+  # with this being the default option for many equipment manufacturers,
+  # and being the strategy recommended in the 2010 ASHRAE journal article
+  # "Economizer High Limit Devices and Why Enthalpy Economizers Don't Work"
+  # by Steven Taylor and Hwakong Cheng.
+  # https://tayloreng.egnyte.com/dl/mN0c9t4WSO/ASHRAE_Journal_-_Economizer_High_Limit_Devices_and_Why_Enthalpy_Economizers_Dont_Work.pdf_
   #
   # @param model [OpenStudio::Model::Model] the model
   # @param climate_zone [String] ASHRAE climate zone, e.g. 'ASHRAE 169-2013-4A'
@@ -2488,7 +2494,7 @@ def model_multiply_schedule(model, day_sch, multiplier, limit)
   # 'ElectronicEnthalpy'
   # 'DifferentialDryBulbAndEnthalpy'
   def model_economizer_type(model, climate_zone)
-    economizer_type = 'DifferentialDryBulb'
+    economizer_type = 'FixedDryBulb'
     return economizer_type
   end
 

lib/openstudio-standards/standards/Standards.AirLoopHVAC.rb

@@ -1060,6 +1060,12 @@ def air_loop_hvac_apply_economizer_limits(air_loop_hvac, climate_zone)
         oa_control.setEconomizerMaximumLimitDryBulbTemperature(drybulb_limit_c)
         OpenStudio.logFree(OpenStudio::Info, 'openstudio.standards.AirLoopHVAC', "For #{air_loop_hvac.name}: Economizer type = #{economizer_type}, dry bulb limit = #{drybulb_limit_f}F")
       end
+      # Some templates include fixed enthalpy limits in addition to fixed dry bulb limits
+      if enthalpy_limit_btu_per_lb
+        enthalpy_limit_j_per_kg = OpenStudio.convert(enthalpy_limit_btu_per_lb, 'Btu/lb', 'J/kg').get
+        oa_control.setEconomizerMaximumLimitEnthalpy(enthalpy_limit_j_per_kg)
+        OpenStudio.logFree(OpenStudio::Info, 'openstudio.standards.AirLoopHVAC', "For #{air_loop_hvac.name}: additional economizer enthalpy limit = #{enthalpy_limit_btu_per_lb}Btu/lb")
+      end
     when 'FixedEnthalpy'
       if enthalpy_limit_btu_per_lb
         enthalpy_limit_j_per_kg = OpenStudio.convert(enthalpy_limit_btu_per_lb, 'Btu/lb', 'J/kg').get

lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2016/ashrae_90_1_2016.AirLoopHVAC.rb

@@ -1,6 +1,38 @@
 class ASHRAE9012016 < ASHRAE901
   # @!group AirLoopHVAC
 
+  # Determine the prototypical economizer type for the model.
+  #
+  # @param model [OpenStudio::Model::Model] OpenStudio model object
+  # @param climate_zone [String] ASHRAE climate zone, e.g. 'ASHRAE 169-2013-4A'
+  # @return [String] the economizer type.  Possible values are:
+  #   'NoEconomizer'
+  #   'FixedDryBulb'
+  #   'FixedEnthalpy'
+  #   'DifferentialDryBulb'
+  #   'DifferentialEnthalpy'
+  #   'FixedDewPointAndDryBulb'
+  #   'ElectronicEnthalpy'
+  #   'DifferentialDryBulbAndEnthalpy'
+  def model_economizer_type(model, climate_zone)
+    economizer_type = case climate_zone
+                      when 'ASHRAE 169-2006-0A',
+                          'ASHRAE 169-2006-1A',
+                          'ASHRAE 169-2006-2A',
+                          'ASHRAE 169-2006-3A',
+                          'ASHRAE 169-2006-4A',
+                          'ASHRAE 169-2013-0A',
+                          'ASHRAE 169-2013-1A',
+                          'ASHRAE 169-2013-2A',
+                          'ASHRAE 169-2013-3A',
+                          'ASHRAE 169-2013-4A'
+                        'DifferentialEnthalpy'
+                      else
+                        'DifferentialDryBulb'
+                      end
+    return economizer_type
+  end
+
   # Determine the limits for the type of economizer present on the AirLoopHVAC, if any.
   #
   # @param air_loop_hvac [OpenStudio::Model::AirLoopHVAC] air loop

lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2016/comstock_ashrae_90_1_2016/comstock_ashrae_90_1_2016.AirLoopHVAC.rb

@@ -0,0 +1,26 @@
+class ComStockASHRAE9012016 < ASHRAE9012016
+  # Determine the prototypical economizer type for the model.
+  # Defaults to FixedDryBulb based on anecdotal evidence of this being
+  # the most common type encountered in the field, combined
+  # with this being the default option for many equipment manufacturers,
+  # and being the strategy recommended in the 2010 ASHRAE journal article
+  # "Economizer High Limit Devices and Why Enthalpy Economizers Don't Work"
+  # by Steven Taylor and Hwakong Cheng.
+  # https://tayloreng.egnyte.com/dl/mN0c9t4WSO/ASHRAE_Journal_-_Economizer_High_Limit_Devices_and_Why_Enthalpy_Economizers_Dont_Work.pdf_
+  #
+  # @param model [OpenStudio::Model::Model] the model
+  # @param climate_zone [String] ASHRAE climate zone, e.g. 'ASHRAE 169-2013-4A'
+  # @return [String] the economizer type.  Possible values are:
+  # 'NoEconomizer'
+  # 'FixedDryBulb'
+  # 'FixedEnthalpy'
+  # 'DifferentialDryBulb'
+  # 'DifferentialEnthalpy'
+  # 'FixedDewPointAndDryBulb'
+  # 'ElectronicEnthalpy'
+  # 'DifferentialDryBulbAndEnthalpy'
+  def model_economizer_type(model, climate_zone)
+    economizer_type = 'FixedDryBulb'
+    return economizer_type
+  end
+end

lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2019/ashrae_90_1_2019.AirLoopHVAC.rb

@@ -1,6 +1,38 @@
 class ASHRAE9012019 < ASHRAE901
   # @!group AirLoopHVAC
 
+  # Determine the prototypical economizer type for the model.
+  #
+  # @param model [OpenStudio::Model::Model] OpenStudio model object
+  # @param climate_zone [String] ASHRAE climate zone, e.g. 'ASHRAE 169-2013-4A'
+  # @return [String] the economizer type.  Possible values are:
+  #   'NoEconomizer'
+  #   'FixedDryBulb'
+  #   'FixedEnthalpy'
+  #   'DifferentialDryBulb'
+  #   'DifferentialEnthalpy'
+  #   'FixedDewPointAndDryBulb'
+  #   'ElectronicEnthalpy'
+  #   'DifferentialDryBulbAndEnthalpy'
+  def model_economizer_type(model, climate_zone)
+    economizer_type = case climate_zone
+                      when 'ASHRAE 169-2006-0A',
+                          'ASHRAE 169-2006-1A',
+                          'ASHRAE 169-2006-2A',
+                          'ASHRAE 169-2006-3A',
+                          'ASHRAE 169-2006-4A',
+                          'ASHRAE 169-2013-0A',
+                          'ASHRAE 169-2013-1A',
+                          'ASHRAE 169-2013-2A',
+                          'ASHRAE 169-2013-3A',
+                          'ASHRAE 169-2013-4A'
+                        'DifferentialEnthalpy'
+                      else
+                        'DifferentialDryBulb'
+                      end
+    return economizer_type
+  end
+
   # Determine the limits for the type of economizer present on the AirLoopHVAC, if any.
   #
   # @param air_loop_hvac [OpenStudio::Model::AirLoopHVAC] air loop

lib/openstudio-standards/standards/ashrae_90_1/ashrae_90_1_2019/comstock_ashrae_90_1_2019/comstock_ashrae_90_1_2019.AirLoopHVAC.rb

@@ -0,0 +1,26 @@
+class ComStockASHRAE9012019 < ASHRAE9012019
+  # Determine the prototypical economizer type for the model.
+  # Defaults to FixedDryBulb based on anecdotal evidence of this being
+  # the most common type encountered in the field, combined
+  # with this being the default option for many equipment manufacturers,
+  # and being the strategy recommended in the 2010 ASHRAE journal article
+  # "Economizer High Limit Devices and Why Enthalpy Economizers Don't Work"
+  # by Steven Taylor and Hwakong Cheng.
+  # https://tayloreng.egnyte.com/dl/mN0c9t4WSO/ASHRAE_Journal_-_Economizer_High_Limit_Devices_and_Why_Enthalpy_Economizers_Dont_Work.pdf_
+  #
+  # @param model [OpenStudio::Model::Model] the model
+  # @param climate_zone [String] ASHRAE climate zone, e.g. 'ASHRAE 169-2013-4A'
+  # @return [String] the economizer type.  Possible values are:
+  # 'NoEconomizer'
+  # 'FixedDryBulb'
+  # 'FixedEnthalpy'
+  # 'DifferentialDryBulb'
+  # 'DifferentialEnthalpy'
+  # 'FixedDewPointAndDryBulb'
+  # 'ElectronicEnthalpy'
+  # 'DifferentialDryBulbAndEnthalpy'
+  def model_economizer_type(model, climate_zone)
+    economizer_type = 'FixedDryBulb'
+    return economizer_type
+  end
+end