Page 190 - The Engineering Guide to LEED-New Construction Sustainable Construction for Engineers

168 Cha pte r F o u r

Average Energy Costs by State (CSAECS) and the median data in the DOE EIA 1999
Commercial Buildings Energy Consumption Survey for electrical (CBECSE ) and for
j
fuel use (CBECSF ) for usage j are usually used as default values, although it is preferred
j
that actual local energy cost rates be used. Additional exceptions to these default values
should be documented, and explanations should be given in the submittals with
supporting data. So for all projects that do not seek Option 1 of EAc1, the design energy
cost is this BAEC, whose default value is calculated by using Eq. (4.2.1). The GFA in
Eq. (4.2.1) is the gross floor area of the building as defined in Chap. 2. (If the project
is made up of several buildings or building portions with different uses as listed in
Table 4.2.3, then the commercial building energy consumptions should be separately
analyzed for each portion, multiplied by the gross floor area in that building portion, and
summed to obtain the BAEC.)

BAEC = [(CSAECSE × CBECSE ) + (CSAECSF × CBECSF )](GFA)
i j i j
for state/district i and use j (if EAc1 Option 1 is not sought) (4.2.1)
Now the PDEM for projects using Option 1 of EAc1 and the BAEC for all other projects
are used to determine the percent renewable energy (PREPDEM or PREBAEC) as a
percent of the PDEM or BAEC, respectively, to determine the credit points listed in the
Requirements section for EAc2. For projects that seek points via Option 1 of EAc1:

REC
PREPDEM = 100 × if EAc1 Option 1 is sought (4.2.2)
PDEM
and for all other projects

PREBAEC = 100 × REC if EAc1 Option 1 is not sought (4.2.3)
BAEC

Special Circumstances and Exemplary Performance
Environmental attributes which are associated with the on-site renewable energy for
EAc2 cannot be sold; they must be retained or retired. More information on current
renewable energy options can be found on the websites of the DOE National Renewable
Energy Laboratory (NREL), the DOE Energy Information Administration (EIA),
Distributed Energy—The Journal for Onsite Power Solutions, and the EPA Clean Energy
program. LEED 2009 also allows for sales of RECs but with restrictions to encourage
on-site RECs over off-site RECs. These restrictions are listed in the LEED 2009 Reference
Guide.
There were no exemplary performance points associated with this credit for
version 2.2, whereas version 2009 allows for an EP point for a 15% reduction as noted
in Table 4.2.1.

4.3 EA Credit 3: Enhanced Commissioning
The intent of EAc3 is to gain even more benefits for system efficiencies and reliabilities
by enhancing the commissioning process. LEED 2009 awards two points for this credit
(LEED 2.2 awarded one point).