Once a bundle of projects has been identified, facility managers should also determine whether a reduction in maintenance expenses can legitimately be anticipated. Facility managers should determine if deferred capital renewal should be part of the analysis to justify large energy upgrades.
An example of additional maintenance savings that will lower the simple payback is a lighting project that changes out incandescent bulbs to CFL or LED bulbs. The typical lifespan of an incandescent light is approximately 1,200 hours, while a CFL has a life span of 8,000 to 10,000 hours and a LED light has a life span of 20,000 to 50,000 hours. The cost of the material and the time for repeatedly replacing the bulbs should be included in the analysis to identify the entire savings for the energy conservation measure.
Another maintenance savings example is replacing building pneumatic controls with a direct digital control (DDC) system. Pneumatic control systems use compressed air, which is typically generated by a compressor (or series of compressors, depending on the size of the system; some rare installations use nitrogen or other bottled gas). Typically the annual maintenance can be 40 man-hours for inspections and the scheduled monthly maintenance service required.
If this work is completed by a third party it is easily tracked and identified, but it is more difficult to identify the hours if this work is completed in house.
Steps Beyond Simple Payback To Justify Large Energy Efficiency Investments
How Bundling Energy Efficiency Projects Helps Justify Large Capital Upgrades
Maintenance Savings May Help Justify HVAC Capital Investments
Deferred Capital Renewal Can Be Used To Justify HVAC Upgrades