Please Confirm that the equation for “project percent improvement PCI below PCIt “ as mentioned at the credit is following :
[( PCIt- PCI)/ PCIt ]*100 (1)
If so, I have following considerations about the credit “Optimize Energy Performance” LEED v4.1. that I would like to share with you.
For Example let’s say that we have following case: A Retail with more than 5 floors in climate Zone 3A with a central Heat Pump (it uses only electricity, no fossil oil) and it has no unregulated energy.
Since in the proposed building and in the Baseline we have only electricity and no fossil foil the electricity cost rate and GHG emission factor are proportional with kWhel per year. So in the equations below we will use only kWhours per year (kWhel).
Assuming the Proposed Building Performance =ProposedkWhel and
Baseline Energy Performance = BaselinekWhel
According Section 4.2.11, Table 188.8.131.52 and Appendix G of ASHRAE there is
PCI = ProposedkWhel/ BaselinekWhel (2)
PCIt= (0+BPF* BaselinekWhel)/ BaselinekWhel = BPF (3)
If our project team targets to get 10 points in the credit “ Optimize Energy Performance” via 4.1 then (1) should be equal 0.25 (according Table 1 and Table 2 of the credit).
Combining (1),(2),(3) =>
[( PCIt- PCI)/ PCIt ] =0.25 <=>
[BPF – ( ProposedkWhel/ BaselinekWhel)]/BPF= 0.25 <=>
[BPF – ( ProposedkWhel/ BaselinekWhel)] =0.25* BPF <=>
BPF *(1-0.25) = ProposedkWhel/ BaselinekWhel <=>
BPF = 0.54 (according Table 184.108.40.206 ASHRAE)
0.54*0.75 = ProposedkWhel/ BaselinekWhel <=>
0.405* Baseline = ProposedkWhel (4)
So the conclusion is that in order to get 10 points the prosposed performance must be the 40.5% of the performance of the baseline.
- The baseline of ΑSHRAE 2016 is worst than ASHRAE 2010, but I am wondering if (4) could be reached.
- Assuming that the baseline building would be the same in ASHRAE 2010 and 2016 and we would follow LEED v4 for the credit Optimize Energy Performance
Then the Points percentage for improvement in Energy performance according Version v4 is
[(Baseline Performance – Proposed Performance) / Baseline Performance ] *100 (5)
Combining (4), (5) =>
[(Baseline Performance – 0.405* Baseline Performance) / Baseline Performance ] *100 = (1-0.405)*100 =59,5% according Table 1 of version 4 this would give us to 18 points.
Do we expect so major changes in this credit between the two credits?
Thank you for your time of reading this, I would appreciate your comments, thoughts, considerations.