Energy use in buildings could drop with a proposed addendum to ANSI/ASHRAE/IESNA Standard 90.1-2007, Energy Standard for Buildings Except Low-Rise Residential Buildings, regulating ventilation and cab lighting in elevators.
Proposed Addendum df to Standard 90.1 takes a first step in addressing inefficiency of ventilation fans and cab lighting, both of which often operate 24/7, regardless of load or occupancy. The addendum is one of 12 proposed addenda to the standard currently out for public comment.
The American Council for an Energy-Efficient Economy and the European E4 Committee estimate elevator energy use to be in the range of 2 to 5 percent of total building electric consumption. Proposed Addendum df would require cab lighting systems to have efficacy of not less than 35 lumens per watt, that cab ventilation fans for elevators without air conditioning shall not consume over 0.7 W*s/L at maximum speed, and that when stopped and unoccupied with doors closed for more than 15 min, cab interior lighting and ventilation shall be de-energized until required for operation.
Also open for public review is proposed Addendum di, which sets requirements for parking-garage ventilation. In 1999, the standard required garage ventilation fan systems with a total design capacity greater than 30,000 cfm to have either an automatic control capable of staging fans or modeling fan volume or an automatic control capable of shutting off fans or reducing fan volume when the garage is not in use.
The 2007 ASHRAE Handbook “HVAC Applications” recommends, “If permitted by local codes, the ventilation airflow rate should be varied to conserve energy.” The proposed flow rates and concentrations in the addendum are from the International Mechanical Code requirements.
Proposed addenda for Standard 90.1 currently open for review are:
For Public Review Until May 9:
• Addendum ck allows for more flexibility in meeting ventilation requirements by referencing the ANSI/ASHRAE Standard 62.1, Ventilation for Acceptable Indoor Air Quality, definition of system-ventilation efficiency and not the variables used in the Standard 62.1 multiple-spaces equation.
• Addendum db provides an exception for certain systems serving laboratory spaces from the design airflow-rate requirement in Appendix G. Additionally, it clarifies that the system fan power shall have the same proportion as in the proposed design.
• Addendum de splits the “generic lobby” from common elevator lobbies in the lighting-power-density (LPD) tables with adjusted LPDs to reflect specific space needs for elevator and non-elevator lobby spaces. Additionally, this removes fitness-center audience seating from the LPD table.
• Addendum df takes a first step in addressing ventilation and cab lighting in elevators regardless of occupancy.
• Addendum dg adds a definition for the term “field-fabricated fenestration” used in section 5.4.3.2, consistent with an official interpretation approved by the Standard 90.1 committee and similar language in California’s Title 24.
• Addendum dh clarifies the credit for on-site renewable energy and site-recovered energy in Section 11 and Appendix G.
• Addendum di sets requirements for parking-garage ventilation.
• Addendum dk adds clarity and instruction to the users of Appendix C, the envelope trade-off option, for new skylighting and daylighting requirements that were added in addenda al, bc, and bn.
• Addendum dl gives instruction to the users of Appendix C on how to model the base envelope design and the proposed envelope design on how to comply with the cool roof provisions of Section 5.
• Addendum do attempts to clearly establish the goals and requirements of the lighting system to ensure that owners are provided all of the information necessary to best use and maintain the lighting systems.
For Public Review Until May 24:
• Addendum dj limits the fan energy allowance for energy-recovery devices to values that approximate the results of the economic analysis performed for the previously approved Addendum e, with some allowance to permit adequate pressure drop for products near the minimum recovery effectiveness of 50 percent. A separate allowance also is created for coil runaround loop systems.
• Addendum dn shows changes in Appendix G relative to Addendum cj (warehouses) to Standard 90.1.
The proposed addenda to Standard 90.1 are available for comment only during their public-review period. To read the addenda or to comment, visit www.ashrae.org/publicreviews.
If no comments are received on these addenda, they likely will be incorporated into the 2010 version of the standard slated to be published this fall. If comments are received, the substance and volume of those comments will determine whether they are incorporated into the 2010 standard.