ASHRAE Journal - August 2009 - 19

Year 1999 2001 2003 2004 2007 2010 2013 2015 2020 2025 2030 ASHRAE Standard 90.1* 52.95 51.6 – 43.75 40.60 30.6* 27.0* 23.0* 18.0* 14.0* 10.0* ASHRAE Standard 90.1† – – – 70.70 – 49.0 42.0 36.0 24.0 18.0 16.0 ASHRAE Standard 189.1 1** – – – – 33.1 28.2 24.7 18.0 12.6 6.3 0.0 2§ – – – – 49.00 40.95 36.10 31.85 18.20 9.10 0.00 ASHRAE Advanced Energy Design Guides# – – – – 37.3 26.7 24.0 18.0 0.0 0.0 0.0 CBECS Survey Data 85.1 – 91.0 – – – – – – – – AIA 2030 – – – 51 – 36 – 27 18 9 0 Federal Targets EISA 433 – – – – – 40.95 – 31.85 18.20 9.10 0.00 *Excludes plug and process loads. †Including plug and process loads. **Targeted at 30% below Standard 90.1-2004 (excludes plug and process loads). §Targeted at 30% below Standard 90.1-2004 (includes plug and process loads). #Targeted at 30% below Standard 90.1 for 2007 – 09; 50% for 2009 – 11; and net zero 2013 – 15. Table 1: Comparison chart of energy site EUI goals kBtu/ft2 · year. aggregate energy usages of 23,000 Btu/ft2·yr and to the 2020 target of 18,000 Btu/ft2·yr based upon building types and climate zones. I frankly cannot believe that you can get there by incremental changes to the building envelope or system components. Such targets will dictate things like building orientation, use of daylighting and natural ventilation. They will almost assuredly dictate system selection such as GSHP, DOAS and radiant heating/cooling. So, our path forward for Standard 90.1 is challenging, to say the least, if we are to maintain our momentum and leadership in this area. But we can get there by taking these steps: • Revise the standard to include plug and process loads for consistency with CBECS and other benchmarks; • Consider performance-based analysis for determining prescriptive options; • Consider cost-based site EUIs, perhaps using the energy budgets developed by DOE for the 18 building types and representative cities in eight climate zones; and • Develop the User’s Manual so that it can be published simultaneously with the standard. Standard 189.1 While Standard 90.1 will remain our preeminent baseline tool as a minimum code basis for energy conservation, the big emphasis today is on high performance buildings; and, here again, we need to lead the way with Standard 189.1 for high performance sustainable building design and construction. High performance green building Standard 189.1 was targeted to be 30% higher efficiency in 2007 and a further 15% or so by 2010 with similar reductions in energy use for 2015 and 2020. The standard is based on total energy use, including plug and process loads. We need to publish this standard and continue its development to lead the way for code intended standards and to be progressively more efficient than 90.1-2010 and continuing until we achieve net zero by 2030. August 2009 So, our path forward for Standard 189.1 is clear: • It is critical that we publish 189.1 in 2009 to provide this essential guidance for high performance green and sustainable buildings; • We already need to be working on the second edition of 189.1 so that it maintains its leadership role ahead of 90.1 and towards our net-zero energy target; • We may need to consider two tiers of energy requirements within the standard (one aimed at minimum compliance levels to maximize market acceptance and transformation and the other an aggressive high performance level); • We must develop a clear timeline towards our goal of net zero by 2030 with, perhaps, the high performance level achieving that goal in 2020; • We need to be working on a user’s manual to support the standard. If you put these goals for the AEDGs, Standard 90.1 and Standard 189.1 together into graphical form you get a clear picture of the path that we are on. As an organization we need to set clear targets for these three energy efficiency vehicles: AEDGs, 90.1 and 189.1 since these will certainly impact system design and selection. Table 1 indicates suggested provisional numbers for these standards. There are three key numbers on this table that determine all others. • Under Standard 90.1, the 2004 43.75 kBtu/ft2·year is based on the newly released DOE determination numbers. • Under Standard 90.1, the 2010 49.0 kBtu/ft2·year is based on the NREL adaptation of the 90.1 data into the CBECS format including plug and process loads. • Under the CBECS Survey Data, the 91.0 kBtu/ft2·year is based on the 2003 survey results including plug and process loads. Standard 100 While Standards 90.1 and 189.1 address elements of major renovations for existing buildings, only Standard 100 proASHRAE Journal 19

ASHRAE Journal - August 2009

Table of Contents for the Digital Edition of ASHRAE Journal - August 2009