OK...so I feel kind of dumb asking this question because it seems like I should be able to figure out the answer from the 2009 User Guide but of course it's clear as mud so I humbly ask for clarification on the intent of credit EA-1 as it applies to LEED CS. By the way this is a two part question.
1. When pursuing LEED CS which of the following applies?
a.) Model energy use of both common area and tenant areas but only include energy cost of common areas in final EA-1 percentage savings calculation. This seems to be the common sense answer and the reason for stipulating that tenant and common areas be modeled on separate utility meters.
b.) Model energy use of both common area and tenant areas and calculate EA-1 energy cost savings including both common area and tenant area energy costs. If this is the answer why would I need to take the step of modeling common area and tenant areas on separate meters if I am including ALL energy costs in the final answer?
c.) Some other reasonable explanation
2. The 2009 User guide appears to have a contradiction with regard to how tenant area lighting is to be treated. The Table in the Option 1 section of the User Guide for Credit EA-1 says to model as-designed tenant area lighting in the proposed design model and Code baseline lighting in the baseline. However two pages later the paragraph at the top of the page says that energy measures applied to tenant areas must be stipulated in the tenant lease in order to qualify for credit.
Which of the following is the correct interpretation if I have a project where the tenant area final lighting design has been completed during design but the performance of that lighting system is not included in the tenant lease?
a.) When final tenant space lighting (not temporary lighting) is designed as part of the core and shell design, savings from the final fit-out lighting design can be claimed even though the performance is not stipulated in the lease.
b.) If final tenant lighting is designed the savings cannot be claimed unless the design performance is stipulated in the lease, therefore the tenant area lighting should be the same as the baseline and the table is incorrect.
c.) There is another perfectly logical interpretation.
d.) We purposefully intended to make it confusing so that GBCI would be confused and therefore review comments would be inconsistant and engineers would curse our names while we chortle under our breaths at the pain they now must endure.
Thanks for your prompt help and best wishes for the Holidays.
PS: For purposes of full disclosure this post does include sarcasm.
Susann Geithner
PrincipalEmerald Built Environments
1297 thumbs up
December 20, 2010 - 12:35 pm
We just finished two LEED CS projects. So here is my experience and the reviewers guidance:
#1 b) is correct, but you are only allowed to calculated the actual tenant design for lighting, if it is required by the lease. Otherwise you will have to assume baseline power density, so basically you don't claim savings for the lighting. However you can claim savings for any measures, which you require within the tenant built-out like motion sensored lighting (beyond ASHREA mandatory provisions requirements) or daylighting sensored lighting. Owner spaces like main lobby, stairs, basement parking are to be calculated as per actual design and in the baseline building with ASHRAE standard.
#2 b) is the correct answer and I think d) is probably correct also. ;)
In regards to the metering (separate user), this is basically to help the reviewer see, what you have claim savings for and also if you do the measurement and verification as well as EA C6 Green power this is were it comes into play. Because you have to measure 80% of your energy consumption and you only have to purchase green power for the electrical energy consumed by the owner's portion of the building. The LEED guide says calculated it based on BOMA areas, but the reviewer may also accept your more accurate approach with seperate meters. That usually ends up being less green power. I hope that helps.
Happy Holidays
Michael Tillou
Director of Energy ServicesCannon Design
52 thumbs up
December 21, 2010 - 11:20 am
Thanks. I sort of assumed that "b" was going to be the answer.
Christopher Schaffner
CEO & FounderThe Green Engineer
LEEDuser Expert
963 thumbs up
January 27, 2011 - 9:29 am
The answers are different for CS-2.0 and CS-2009 projects.
For CS-2.0 it is a & a
For CS-2009 it is b & a
For #2 if the lighting is in the core shell scope, then it is part of the project, and can be modeled as designed.
Susann Geithner
PrincipalEmerald Built Environments
1297 thumbs up
February 28, 2011 - 2:09 pm
I do have to disagree. I have submitted 4 LEED CS 2009 projects within the last year. The reviewers comment always said that we can only claim savings for the lighting, if the lease or anything else requires the tenant to install or design to that level. For instance we have tried to claim savings for daylight sensors, but we could only use the savings to our advantage by showing that this tied into a BAS system controlled by a weather station on the roof, which controls the dimming of each lighting fixture and dim it up or down. So even if the owner is supplying the lighting or paying for it, you can only make it count if the owner actually determines the lighting power density not just pays for the lighting.
I think the reasoning behind this is that your tenant might move out after 2 years and then you might not have the same lighting power unless you actually require it.