DATE JULY 20, 2011
MEMORANDUM

SUBJECT:OVERRIDE FOR EXTREME AMBIENT TEMPERATURES
FROM:  	Victor McMahan, OTAQ/Transportation and Regional Programs Division
	   	
TO:	Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Heavy-Duty Engines and Vehicles; Docket EPA-HQ-OAR-2010-0162

Purpose / Background:
      
      March 9, 2011 email communication with staff of the Texas Transportation Institute (TTI) on preliminary environmental chamber test results on the performance of idle reduction technologies in extreme ambient temperature conditions (see below)

Discussion:

From:	"Zietsman, Joe" <Zietsman@tamu.edu>
To:	Victor McMahan/DC/USEPA/US@EPA
Cc:	"Johnson, Jeremy" <j-johnson@TTIMAIL.TAMU.EDU>, "Lee, Doh-Won" <leedw@tamu.edu>
Date:	03/09/2011 03:39 PM
Subject:	Temperatures

Victor,
 
Here is what we found for chamber temperatures at 100 and 0 degrees. 
 
In-Cabin Target Temperature (73 °F)
 
Average Temperature Maintained during the Hot Test (at 100 °F)
Average Temperature Maintained during the Cold Test (at 0 °F)
Diesel Powered APU #1
73
64*
Diesel Powered APU #2
71
73
Battery Powered APU #1
80
 
Battery Powered APU #2
83
 
Diesel Operated Heater #1
 
62
Diesel Operated Heater #2
 
50

*APU was set at 73° F.  It probably would have reached higher temperatures if it was set at a higher temperature. 
Also, please note that the Battery Powered APUs did not have heaters connected to them so we could not run the cold tests on them. 
 
If you need anything else or more, please, let me know
  
      Let me know if you need anything else.
Joe
Conclusion:
      The information from the email communication with TTI was used to inform the discussion on the performance of idle reduction technologies in extreme ambient temperature conditions and decision to adopt the Automatic Engine Shutdown override for extreme ambient temperatures. 
