Energy Management and Control Systems Flashcards
6 cards from real CEM practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Energy Management and Control Systems flashcards as text
Measurement and Verification (M&V) following an energy efficiency project is performed to:
Answer: Quantify actual energy savings achieved compared to a pre-retrofit baseline
M&V uses the IPMVP framework to measure actual post-retrofit energy use and compare it to an adjusted baseline, confirming that projected savings were actually achieved.
A building energy benchmark using ENERGY STAR Portfolio Manager allows a facility manager to:
Answer: Compare the building's energy performance against similar buildings nationally
ENERGY STAR Portfolio Manager normalizes building energy data by type, size, location, and occupancy to generate a 1-100 score comparing performance to peer buildings nationally.
Interval metering (15-minute or hourly data) is more useful than monthly utility bills for energy management because it:
Answer: Reveals load profiles, peak demand events, and operational anomalies not visible in monthly totals
Interval data shows exactly when energy is consumed, enabling identification of after-hours baseload, demand peaks, and equipment scheduling issues that monthly bills completely obscure.
Retro-commissioning (RCx) of an existing building typically targets:
Answer: Restoring building systems to optimum performance through operational and control improvements
RCx investigates and corrects faults, control errors, and operational deficiencies in existing building systems, often achieving significant savings with minimal capital investment.
Submetering in a building provides energy managers the ability to:
Answer: Isolate energy consumption by system, floor, or tenant for targeted efficiency improvements
Submeters break down total building consumption into components (HVAC, lighting, plug loads) or areas (floors, tenants), enabling targeted identification and reduction of waste.
The primary purpose of a calibrated energy simulation model used in M&V is to:
Answer: Create a reliable baseline against which post-retrofit measured consumption is compared
A calibrated simulation is adjusted until its outputs closely match actual measured pre-retrofit data, creating a credible baseline model for calculating savings under Option D of IPMVP.