Concepts and Principles Flashcards
7 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 7 Concepts and Principles flashcards as text
What is 'life-cycle cost analysis' (LCCA) primarily used for in energy management?
Answer: Evaluating total cost of ownership including initial, operating, and disposal costs
LCCA compares the total costs—capital, operating, maintenance, and disposal—of alternative investments over their useful lives to identify the most cost-effective option.
The 'rebound effect' in energy efficiency refers to:
Answer: Increased energy use resulting from cost savings generated by efficiency improvements
The rebound effect occurs when money saved through efficiency improvements is spent on additional energy-consuming activities, partially offsetting the savings.
In energy auditing, what does 'envelope' refer to?
Answer: The physical boundary between conditioned and unconditioned space
The building envelope is the shell—walls, roof, windows, and foundation—that separates the interior conditioned space from the outdoor environment.
What is the significance of the 'coincident peak demand' for a utility customer?
Answer: It is the customer's demand at the moment the utility's system peak occurs
Coincident peak demand is the customer's load at the time the utility's grid-wide peak occurs, often used to allocate transmission and capacity costs.
Which of the following is an example of an 'energy conservation measure' (ECM) targeting the building envelope?
Answer: Adding insulation to the roof to reduce heat gain
Adding roof insulation directly improves the thermal performance of the building envelope, reducing heat transfer and cooling/heating loads.
What is 'net present value' (NPV) and how is it used in energy project decisions?
Answer: The difference between the present value of cash inflows and outflows over a project's life
NPV discounts future cash flows to today's dollars; a positive NPV indicates the project generates more value than its cost of capital and is financially worthwhile.
In the context of CEM exam preparation, what does 'degree-day' data help energy managers analyze?
Answer: Weather-normalized heating or cooling energy consumption
Heating and cooling degree-days normalize energy data for weather variation, enabling fair year-over-year or site-to-site comparisons of thermal energy use.