Envelope Strategies

Topic: Roof, wall and window strategies for cost-effectively exceeding WSEC and beating ELCCA prescriptive thermal performance criteria.

...develop table comparing App. G, WSEC and ELCCA envelope thermal performance values.

Outdoor Air Load Estimator

Topic: A nifty Java-based outdoor air load calculator, courtesy of ArchEnergy Inc.

Consider this calculator, which includes American and Canadian weather tables, for reality checking energy recovery numbers calculated by energy modeling programs. Following is a sample output report:

********************************************************************************************

Result summary for Calculation Number: 5
Location: BURLINGTON, Vermont
Elevation: 341 ft
Operating Hours: 0:00 o'clock until 0:00 o'clock
Hours of Operation: 24
Makeup Air Flow: 183000 cfm
Thermostat Setpoints: Heating = 68 F, Cooling = 72 F

Dehumidification was set to limit the Relative Humidity to: No Dehumidification

Heating was locked out during: --
Cooling was locked out during: --

The Lockout of Heating or Cooling systems resulted in...
Insufficient Heating during: --
Insufficient Cooling during: --

The Heating Design Load is: 18891.3 kBtu/h
The Cooling Design Load is: 4754.9 kBtu/h

Calculated Monthly loads:
Month Heating Load Cooling Load
January : 7,847,593 kBtu 0 kBtu
February : 7,329,964 kBtu 0 kBtu
March : 6,296,320 kBtu 0 kBtu
April : 3,911,545 kBtu 28,900 kBtu
May : 1,574,753 kBtu 97,140 kBtu
June : 889,352 kBtu 128,736 kBtu
July : 399,761 kBtu 382,194 kBtu
August : 532,923 kBtu 221,369 kBtu
September : 1,517,449 kBtu 33,329 kBtu
October : 2,836,548 kBtu 0 kBtu
November : 4,821,821 kBtu 0 kBtu
December : 6,956,354 kBtu 0 kBtu
Total_Year : 44,914,382 kBtu 891,668 kBtu

FAN ENERGY CALCULATIONS:
Supply Exhaust
Total Static Pressure: 3.5 inW 1.0 inW
Fan Type: Forward_Curved Forward_Curved
Fan Efficiency: 63.0 % 63.0 %
Motor Class: Standard Standard
Motor Efficiency: 91.0 % 89.0 %
Motor Output Power: 159.032 HP 45.438 HP
Moter Rated Input: 130.319 kW 38.071 kW
Motor Energy Consumption: 1141594 kWh 333499 kWh
********************************************************************************************

Set system runtimes matching equipment operational schedule to establish an upper bound for energy recovery savings. Here the building is operating at 7x24, and if the rough cost for a therm of natural gas and a kilowatt hour of electricity are $1.20 and $0.10 respectively, then an upper bound on heat recovery savings is:

• 1.20 $/therm * 44,914,382 kBTU / 100 kBTU per therm = $530,973 from gas, and
  
• $0.10 $/kWH * 1,141,594 kWH = $114,160 from electricity,
  
• for a total of $645,133 heating load cost with systems running 24 hours a day, seven days a week, for one year at constant volume.

This number is the maximum theoretical value of the savings, however it cannot be approached without 1) consistent internal heat gains -- heat gains sufficient to keep the exhaust airstream temperature elevated effectively above the outdoor air temperature, and 2) significant fan motor energy expenditures.

What typically happens in laboratory-type buildings is that while there may be a consistent heat recovery demand, the heat available to recover varies widely with occupancy. And likely there will be a number of hours in a 7 x 24 year-round operation when the outside air approaches to within 5° of the exhaust air, rendering energy recovery essentially ineffective.

Have not counted heat recovery from a cooling standpoint, as the number of annual hours where the outside air exceeds the exhaust air by more than 5° F in this climate most likely won't be very compelling.

So for how many hours per year does the exhaust air temperature exceed the outside air and by how much, on the average? Just check that 'Outside & Exhaust Air Loads Report' in the SIM file...if it actually existed, it might tell you...;-) All of the information is calculated and carried in the program, and presumably is output to the SIM file directly and indirectly in various places.

Am hoping to figure a way to pull a report like the above-mentioned together one of these days...if anyone has an Awk-based outside air loads report, even a rudimentary one as a starting point, I'd be much obliged.

ELCCA Standard Systems

Topic: Standard HVAC systems used in typical Washington State schools analyzed in ELCCA reports

Mechanical Alternatives

Displacement Ventilation: Low-velocity floor diffusers, ceiling return for classrooms. Fan powered VAV for administrative areas, constant volume air handler for multipurpose room. Gas-fired instantaneous 95% efficient hot-water condensing boilers provide heating and domestic water needs. DDC controls.

Centralized Air Handlers & Zone Duct Coils: Constant volume centralized air handlers with zone duct heating coils for all areas. Gas-fired 80% efficient cast iron boiler. Gas-fired 80% efficient 100 gallon domestic hot-water heater. DDC controls.


High-Performance & Renewable Alternatives

Ground Loop Heat Pump: High-lift high-efficiency geothermal ground source heat pumps provide both heating and cooling for all areas. Gas-fired instantaneous 95% efficient hot-water condensing boilers provide domestic water needs. DDC controls. Code minimum ventilation. This is also the Renewable Alternative.

eQuest SIM File Data Extraction Using Awk

Topic: Extracting discrete data values using Gawk (GNU Awk)

Following are some (one, for now) potentially useful Gawk (using GNU Awk for Win32) scripts for extracting data from an eQuest/DOE2 output SIM file :

# Save this script to a file named BEPU.AWK in the directory # containing the simulation output files. # # BEPU.AWK extracts energy consumption totals from # the specified .SIM report using GNU Awk for Windows: # # http://gnuwin32.sourceforge.net/packages/gawk.htm # # Note that GAWK.EXE must exist in the shell path. Thus after installation # using the package installer, it is recommended that a copy of GAWK.EXE # be placed in the %WINDIR%\system32 directory. # # Usage: # # gawk -f BEPU.AWK SimFile.SIM # # ...where the program file BEPU.AWK and data file SimFile.SIM must exist. # {if ($2 ~/BEPU/) {ipr = 1}} {if (ipr == 1) {if ($1 == "TOTAL") print $1" "$2" "$3" "$4 if ($2 == "PS-H") ipr = 0}}

At left is a simple Awk script to extract the energy consumption totals in kWH and therms from the specified SIM file. Run this script from a CMD prompt in the same directory as your .SIM files; be sure to copy GAWK.EXE to %WINDIR%\System32, where %WINDIR% is usually (but not always) C:\WINDOWS. Modified from an original script posted by Joe Huang in the BLDG-SIM archives. Thanks Joe! More fun with Awk and SED to come over the next few months, as time permits or workload demands.

Note that in this example, printing is turned on (ipr = 1) by flagging the desired report, and off (ipr = 0) by flagging the report following the desired report. Examine the contents of the SIM file or see this post to determine the actual report sequence -- its not the same as shown in the drop-down box in the SIM file viewer.

More Awk examples from elsewhere...

• Quick and Dirty Data Extraction in AWK from the Linux Journal
  

SED & eQuest SIM File Reports

Topic: Extracting individual reports from SIM files using SED

See this post for another SED vs. Awk comparative editorial. Following is my own take, after fiddling around with SED for a few hours in an attempt accomplish discrete value data extraction.

Next time: Discrete value data extraction using Awk!

SED = Sledgehammer

SED seems most useful for gross editing tasks -- i.e. global search-and-replacements or chunking out reports from the SIM file. SED is essentially batch application of regular expressions.

Lacking basic programming constructs, there are fundamental functionality limitations. But for the tasks it is capable performing, SED accomplishes them exceedingly well.

Awk = Sawzall

With built-in programming language constructs, Awk seems to be more suited for 'refined' tasks like discrete value data extraction, doing arithmetic on arrays and columns, or creating custom reports.

They both seem to be the right tool, just for different tasks. Following are some potentially useful SED examples (using GNU SED for Win32):

SED /HW-BOILER/!d SimFile.SIM	Outputs from SimFile.SIM all lines with HW-BOILER
SED /PS-E/,/PS-F/!d SimFile.SIM	Outputs the PS-E report contained in SimFile.SIM
@ECHO OFF SET SIMRPT=Energy Cost Summary SET SIMBGN=BEPS SET SIMEND=BEPU SED.EXE --version >NUL IF %ERRORLEVEL% GTR 0 GOTO USAGE IF EXIST %1.SIM GOTO NEXT GOTO USAGE :NEXT SED /%SIMBGN%/,/%SIMEND%/!d %1.SIM >%TEMP%\~SED.TMP IF /I "%2" EQU "/A" GOTO APPEND SED /%SIMEND%/d %TEMP%\~SED.TMP GOTO :EOF :APPEND SED /%SIMEND%/d %TEMP%\~SED.TMP >>%0.RPT GOTO :EOF :USAGE ECHO. ECHO The %SIMBGN%.CMD script extracts the "%SIMRPT%" section from ECHO the specified .SIM report using GNU SED for Windows: ECHO. ECHO http://gnuwin32.sourceforge.net/packages/sed.htm ECHO. ECHO Note that SED.EXE must exist in the shell path. Thus after installation ECHO using the package installer, it is recommended that a copy of SED.EXE ECHO be placed in the %WINDIR%\system32 directory. ECHO. ECHO Usage: ECHO. ECHO %SIMBGN% SimFile [/A] ECHO. ECHO ...where SimFile is specified without the .SIM extension and must exist. ECHO If the optional /A parameter is supplied, the output will be appended to ECHO a file named %SIMBGN%.RPT so that a 'FOR' command may collect ECHO all %SIMBGN% reports into a single file for further processing. ECHO. ECHO Example: ECHO. ECHO FOR %%i in (*.SIM) DO %SIMBGN% "%%~ni" /A ECHO. ECHO CAUTION!!! The %SIMBGN%.RPT file must be deleted manually ECHO to be refreshed, else updates will simply be appended to it. ECHO. ECHO Released to public domain under General Public Licence (GPL) ECHO http://www.gnu.org/licenses/gpl.html ECHO Copyright 2007 by Brandon Nichols, PE ECHO.	The command script at left extracts the BEPS report from the specified .SIM file and echoes it to the screen by default. Copy the code, paste it to a blank Notepad window. Save the file as 'BEPS.CMD' (be sure to change the drop-down in the Notepad file-save dialog from '*.txt' to 'All Files') to the eQuest reports directory, or to a designated script directory in the command path. Assure that GNU SED.EXE may also be found in the command path -- see the installation tip under 'USAGE' in the script. Type 'BEPS SimFile' at the CMD prompt, where SimFile is specified WITHOUT the .SIM extension. Now for some real fun type 'BEPS' at the CMD prompt and hit return, then copy/paste the 'FOR' example displayed on the 'Usage' screen to the CMD prompt and hit return. Written to disk will be each BEPS report from all simulations in a directory into a text file named BEPS.RPT for output or further processing. To create your own report extractor, simply change the three 'SET' values at the top of the file and save it under a new name. For instance changing values of SIMRPT to Summary of Utility Rates, SIMBGN to BEPU, and SIMEND to PS-H creates a BEPU extractor.

When creating a new report extractor, examine the contents of the SIM file or see this post to determine the actual report order -- its not the same as shown in the drop-down box in the SIM file viewer.

Perhaps not immediately obvious, but a 'System Report Extractor' for a report within the SIM file 'system repeat block' will extract each instance of the report for all systems! For example, copy the script above to Notepad and change the values of SIMRPT to 'System Utility Energy Use', SIMBGN to 'SS-H', and SIMEND to 'SS-I' and save to SS-H.CMD (be sure to change the drop-down in the Notepad file-save dialog from '*.txt' to 'All Files') in same directory where the SIM files are located. Thus created is an SS-H extractor that extracts all System Utility Energy Use reports for every system from the specified SIM file!.

Type 'SS-H SimFile' (without the .SIM extension) at the command line to test the output. Note that SimFile must exist in the same directory as the script and GNU SED.EXE must be in the command search path. If the above conditions have been met and your syntax is correct, then all SS-H reports will be echoed sequentially to the screen.

Now type just 'SS-H' at the command line and hit return. Then copy/paste the 'FOR' example from the usage screen to the command line and hit return. Congratulations, you have just created the text file SS-H.RPT, containing each System Utility Energy Use report for every system from all SIM files in the current directory!

eQuest SIM File Reports

Topic: A listing of the reports in the order found in the DOE2 .SIM output file

LV-M	DOE-2.2 Units Conversion Table
LV-N	Building Coordinate Geometry
LV-A	General Project Parameters
LV-B	Summary of Spaces
LV-C	Details of Space
LV-D	Details of Exterior Surfaces
LV-E	Details of Underground Surfaces
LV-F	Details of Interior Surfaces
LV-G	Details of Schedules
LV-H	Details of Windows
LV-I	Details of Constructions
LV-J	Details of Building Shades
LS-A	Space Peak Loads Summary
LS-B	Space Peak Loads Components
LS-C	Building Peak Load Components
LS-D	Building Monthly Loads Summary
LS-E	Space Monthly Load Components
LS-F	Building Monthly Load Components
LS-K	Space Input Fuels Summary
LS-K	Building Input Fuels Summary
LS-L	Management and Solar Summary
SV-A	System Design Parameters
SS-D	Building HVAC Load Summary
SS-E	Building HVAC Load Hours
SS-M	Building HVAC Fan Elec Energy
SS-A	System Loads Summary	Begin system repeat
SS-B	System Load Summary Zones	block
SS-C	System Load Hours	|
SS-H	System Utility Energy Use	|
SS-I	Sensible/Latent Summary	|
SS-J	Peak Heating and Cooling	|
SS-K	Space Temperature Summary	This group of
SS-R	Zone Performance Summary	reports is repeated
SS-L	Fan Electric Energy Use	once for each system
SS-N	Relative Humidity Summary	|
SS-P	Heating Performance Summary	|
SS-P	Cooling Performance Summary	|
SS-G	Zone Loads Summary	|
SS-F	Zone Demand Summary	End system repeat
SS-O	Space Temperature Summary	block
PV-A	Plant Design Parameters
PS-A	Plant Energy Utilization
PS-B	Utility and Fuel Use Summary
PS-C	Equipment Loads and Energy Use
PS-D	Circulation Loop Loads
PS-E	Energy End-Use Summary for all Electric Meters
PS-E	Energy End-Use Summary for all Fuel Meters
PS-F	Energy End-Use Summary for Meters
BEPS	Building Energy Performance
BEPU	Building Utility Performance
PS-H	Loads and Energy Usage for Plant
HOURLY REPORT	Hourly Report for Energy End-Usage
EV-A	Life-Cycle Costing Parameters
ES-A	Annual Costs and Savings
ES-B	Life-Cycle Non-Energy Costs
ES-C	Life-Cycle Investment Savings
ES-D	Energy Cost Summary
ES-E	Summary of Utility Rates
ES-F	Block Charges and Ratchets