Appendix B 359
— only half of the anticipated growth from 1,450 hrs to 2,000 hrs
may happen, and— the 9% load fraction may be switched on for 400 hours.- These possible errors could affect the post-retrofit energy use by
as much as about 2,500 kWh, which represents 8.2% of the ex-
pected 30,000 kWh annual savings. The impact of assumptions of
the lighting impact on the electrical demand meter for all twelve
months of the baseyear and post-retrofit years might affect total
reported demand savings by as much as 3%. Neither of these
stipulation impacts is considered significant for the project. - Estimated accuracy of the power measurements is ±4%.
- The savings calculation process shown below was summarized in
the M&V Plan. - Savings are to be computed annually for the subsequent year using
a remeasurement of the lighting electrical load immediately after
ECM completion and on each anniversary thereafter. - The electrical power readings on the baseyear and all future years
will be made by a contract electrician. All data and analyses are
available for inspection. As a check on the readings, building main-
tenance staff will also measure the electrical load at the same times
as the contractor. If there is a difference of more than 4% between
staff and contractor readings, a second contractor reading will be
made and the proper value selected between the two contractor
readings. - This savings determination process is expected to require an elec-
trician 5 hours each year to make the readings and calibrate the
measurement equipment. Total cost each year is expected to be
$200 including reporting,
Baseyear Electricity Use/Demand
The baseyear energy use for Equation 1 is computed by multiply-
ing the 28.8 baseyear load by baseyear load/duration data, above. The
computation is shown below.