I have a multifamily project which will have a noresidential electricity
meter to cover house loads and a residential electrical meter for each
unit. The baseline system is System 2 - PTHP's. The proposed system is
Chilled Water with Electric Heat. Due to the rate structures out here in
Seattle, I'm noticing that the virtual rate in the baseline is
approximately 10% higher than in the proposed. I've tracked it down mainly
to the fact that the baseline "Space Cooling" usage is allocated to the
Residential meters while the Proposed "Space Cooling" is provided by a
chiller that will be on a nonresidential meter. In reality, a terminal
piece of equipment within a residence would be metered by the residential
panel and charged direct to the residence. However, it seems a bit unfair
that the baseline is being penalized strictly based on which meter the
"Space Cooling" is assigned to.
I can't find anything specifically within Appendix G that would tell me to
have the same energy meters or rate structure by system. The LEED
Reference Guide provides guidance that says the same rate schedules shall
be used for the proposed and baseline simulations and building.
Mixed-use buildings seem to be a weak point of Appendix G and I'm wondering
if anyone else has run into this issue before.
Thanks,
Robby Oylear, PE, LEED AP
Robby,
Note to G2.4 states that using the actual rates ".allows users to gain
credit for features that yield load management benefits. Where such features
are not present, users can simply use state average unit prices from EIA".
Assigning in-unit cooling to residential meter in the baseline versus
non-residential meter in the proposed design may produce cost savings, but
these savings are not due to load management benefits (i.e. reducing peak
demand or shifting it away from peak periods) and thus should not be
contributing to the performance rating. So it looks pretty clear to me that
you should be using non-residential meter for space cooling in the baseline.
Maria