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planning:calculating_energy_efficiency:energy_balances_-_background [2014/09/18 18:19] – external edit 127.0.0.1planning:calculating_energy_efficiency:energy_balances_-_background [2020/08/03 14:57] (current) – [Discussion about the purpose of heating] wfeist
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   - There are often critical remarks about the the calculation method too:\\ ** Can (stationary) U-values be used in calculations at all?  Isn't the heat storage more important than the thermal insulation, and isn't the whole U-value calculation method incorrect?**\\ No, the U-value calculation method is the correct approach as has been shown by many systematic analyses (see [[planning:thermal_protection:thermal_protection_works:Thermal protection vs. thermal storage]]). The comparison of the energy balance after the calculation and after the measurement additionally proves this.\\   - There are often critical remarks about the the calculation method too:\\ ** Can (stationary) U-values be used in calculations at all?  Isn't the heat storage more important than the thermal insulation, and isn't the whole U-value calculation method incorrect?**\\ No, the U-value calculation method is the correct approach as has been shown by many systematic analyses (see [[planning:thermal_protection:thermal_protection_works:Thermal protection vs. thermal storage]]). The comparison of the energy balance after the calculation and after the measurement additionally proves this.\\
 \\ \\
 +==== Can a similar approach also be used to calculate the cooling demand? ====
 +
 +Yes, it can. It is exactely the same balance - the utilisation factor will now be applied to potentially remaining heat losses. This is implemented as the active cooling sheet in PHPP.\\
 +
 +It is also possible, to give an assessment of the thermal comfort if no active cooling is available: The is based on the [[:a_simplified_method_for_determining_thermal_comfort_in_summer_for_buildings_without_active_cooling|passive cooling sheet]].
 +  
 +\\ \\
 ===== Reference area: Treated Floor Area ===== ===== Reference area: Treated Floor Area =====
  
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 There are  no "correct" reference values, only more or less "suitable" values.    There are  no "correct" reference values, only more or less "suitable" values.   
   * Borsch-Laaks and others have suggested that **the number of occupants** who live in a house should be referred to (kWh/Person/a).  But what happens when the children grow up and move out?  This is not suitable as a measure for the quality of the building. And it is wise to apply a measure for the quality of the building.\\ \\   * Borsch-Laaks and others have suggested that **the number of occupants** who live in a house should be referred to (kWh/Person/a).  But what happens when the children grow up and move out?  This is not suitable as a measure for the quality of the building. And it is wise to apply a measure for the quality of the building.\\ \\
-  * Others (e.g. the German Engineers Association) prefer to use the **gross volume V** as a reference value (kWh/m³).  Critics claim that with increasing insulation thicknesses, the heating demand would be reduced due to the increased  reference volume alone.  That is nonsense of course - but  other dead volumes can also increase the specific energy value.  This leads to faulty optimisation:  greater volumes are then built than are necessary and therefore they also have better specific values.  That is inappropriate.  .\\ \\+  * Others (e.g. the German Engineers Association) prefer to use the **gross volume V** as a reference value (kWh/m³).  Critics claim that with increasing insulation thicknesses, the heating demand would be reduced due to the increased  reference volume alone.  That is nonsense of course - but  other dead volumes can also increase the specific energy value.  This leads to faulty optimisation:  greater volumes are then built than are necessary and therefore they also have better specific values.  That is inappropriate.\\ \\
   * According to the Energy Saving Ordinance in Germany (EnEV), the** "useable" area A<sub>N</sub>** is simply a gross volume which is linearly converted  to just one area:\\ \\ **A<sub>N</sub> = 0,32 m<sup>-1</sup> V**\\ \\ This "area"  cannot be measured as a real area – it is a purely mathematical value – and it too increases with the level of insulation and with all types of dead volumes, so it is just as inappropriate.\\ \\   * According to the Energy Saving Ordinance in Germany (EnEV), the** "useable" area A<sub>N</sub>** is simply a gross volume which is linearly converted  to just one area:\\ \\ **A<sub>N</sub> = 0,32 m<sup>-1</sup> V**\\ \\ This "area"  cannot be measured as a real area – it is a purely mathematical value – and it too increases with the level of insulation and with all types of dead volumes, so it is just as inappropriate.\\ \\
   * **The gross floor area A<sub>BGF</sub>** is the area of the unfinished  building including all the floors.  It is very easy to determine – but also includes all non-useable areas like the inside and outside wall cross sections, access areas etc..  A<sub>BGF</sub> is the largest of the areas being discussed here.  It is often used in Switzerland (e.g. by MINERGIE®). That is why Swiss values always look good!\\ \\   * **The gross floor area A<sub>BGF</sub>** is the area of the unfinished  building including all the floors.  It is very easy to determine – but also includes all non-useable areas like the inside and outside wall cross sections, access areas etc..  A<sub>BGF</sub> is the largest of the areas being discussed here.  It is often used in Switzerland (e.g. by MINERGIE®). That is why Swiss values always look good!\\ \\
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 === Calculating the Treated Floor Area (TFA) === === Calculating the Treated Floor Area (TFA) ===
 ---- ----
-Here you will find detailed information on how to [[planning:calculating_energy_efficiency:energy_balances_-_background:calculating_the_Treated_Floor_Area| calculate the Treated Floor Area for PHPP calculations]].+Here you will find detailed information on how to [[planning:calculating_energy_efficiency:energy_balances_-_background:calculating_the_Treated_Floor_Area| calculate the Treated Floor Area for PHPP calculations]].  {{:picopen:members_only.png?25|}}
  
 \\ \\
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 **Further reading articles** \\ **Further reading articles** \\
  
-[[planning:calculating_energy_efficiency:energy_balances_-_background:calculating_the_treated_floor_area|]] \\+[[planning:calculating_energy_efficiency:energy_balances_-_background:calculating_the_treated_floor_area|]]  {{:picopen:members_only.png?25|}} \\
  
 [[planning:calculating_energy_efficiency:phpp_-_the_passive_house_planning_package:calculations in hot and humid climates|PHPP calculations in hot and humid climates]] \\ [[planning:calculating_energy_efficiency:phpp_-_the_passive_house_planning_package:calculations in hot and humid climates|PHPP calculations in hot and humid climates]] \\
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 [[planning:calculating_energy_efficiency:phpp_-_the_passive_house_planning_package:Climate data tool|PHPP climate data tool]] \\ [[planning:calculating_energy_efficiency:phpp_-_the_passive_house_planning_package:Climate data tool|PHPP climate data tool]] \\
  
-[[planning:calculating_energy_efficiency:phpp_-_the_passive_house_planning_package:climate_data_tool_for_the_southern_hemisphere|PHPP calculations for the Southern Hemisphere]]  \\+[[planning:calculating_energy_efficiency:phpp_-_the_passive_house_planning_package:climate_data_tool_for_the_southern_hemisphere|PHPP calculations for the Southern Hemisphere]]  {{:picopen:members_only.png?25|}}  \\
  
 [[planning:calculating_energy_efficiency:phpp_-_the_passive_house_planning_package:designPH plugin|"designPH" plugin for Trimble Sketchup]] \\ [[planning:calculating_energy_efficiency:phpp_-_the_passive_house_planning_package:designPH plugin|"designPH" plugin for Trimble Sketchup]] \\
planning/calculating_energy_efficiency/energy_balances_-_background.1411057157.txt.gz · Last modified: 2014/09/18 18:19 by 127.0.0.1