Modeling to the MNECB in canada

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I'm looking for some feedback from anyone who has used EE4 and/or modeled a building against the MNECB 1997 in Canada.

1. How are the Energy Source Adjustment Factors used when modeling a building for LEED against the MNECB? It appears that these factors are meant to be multiplied by the total energy cost from each type of use. I see that at least in LEED Canada NC 1.0/1.1, the calculations for EQ p2 require 25% improvement in energy consumption (not cost) over MNECB. Presumably this requires use of the ESAF in that calculation. However, LEED also requires that calculations for energy savings are based on energy cost. When calculating energy costs, do you have to use the ESAF as well as the different utility rates? Or do you use the actual consumption (without using the ESAF) to figure the cost?

2. The code appears to require use of baseline systems that completely mirror the proposed systems - boiler for boiler, chiller for chiller, multi-zone for multi-zone. How have others found ways to show significant energy savings given this constraint? The newer versions of ASHRAE allow comparison of a proposed ground-source heat pump system, for example, against a boiler heating baseline system, or a VAV system against a packaged system, depending on various factors. But the MNECB and ASHRAE 90.1-1999 don't allow this. I am struggling to see how it would be possible to get more than 20-30% savings given these rules.

Thanks,

Anne Marie Moellenberndt PE LEED AP

Anne M. Moellenberndt's picture
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Item 1 - the ESAF's are used in defining the reference building envelope
parameters -- that is why you must define the primary heating source for
each zone. In practise, you just use the energy consumption & costs
from EE4 to populate the LEED Canada letter template. The ESAF's are
not used in the EA-Cr 1 or EA Pr 2 calculations.

Item 2 - your interpretation is not correct. There is a document called
the Performance Compliance for Buildings which defines the reference
building (automatically generated by EE4). Roughly translated, the
reference building has a single 80% efficient boiler (if you have
hydronic heating in the proposed building, it has 1 or 2 chillers (2 if
your plant exceeds 700 tons) with a COP of 5.2. There are 3 reference
building types -- single zone, residential (hotels, dorms etc) ... and
everything else which has a VAV reference system type.

The MNECB is and old code very easy to beat. Standard design should be
25% better than the MNECB (due mainly to lighting). Good HVAC design
(e.g. condensing boilers, dedicated OA systems and ventilation heat
recovery) can put you 50 to 60% better than the MNECB. (My office is in
a building >75% better than the MNECB, but that is another story).

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