Using a degree-day base of 18°C, calculate the number of cooling degree days (CDD) if the outside temperature is a uniform 25°C throughout the year (365 days/year).
In an ammonia-water absorption chiller, what material is the refrigerant?
Which of the following International Performance Measurement and Verification Protocol (IPMVP) options would you use to verify annual energy savings in a project that upgraded lighting in a large manufacturing plant?
Lighting systems operate with a certain recoverable light loss factor. Control systems with photocell sensor inputs combined with dimming ballasts can be used to regulate dimming levels to maintain a continuous light level in the work space. Which of the following best describes this type of control?
What term describes the difference between the control signal value and the set point?
Using an interest rate of 15%, an energy project has a net-present value (NPV) of $3,500. Which statement is true about the project's internal rate of return (IRR)?
Insulation has a thermal conductivity of 0.04 Watt/(m-°C). What is the R-value for this insulation when it is 5-cm thick?
Infiltration (inward air leakage) in a building is dependent on several factors. Which of the following is least likely to affect or influence infiltration in a building?
A gas-fired boiler is operating with 31.9% excess air. A feedwater economizer is used to reduce the stack temperature rise from 310°C to 160°C. Using the natural gas combustion efficiency tables in your workbook, find the energy savings from the economizer as a percentage of historical fuel consumption.
A heat pump water heater has an annual average coefficient of performance (COP) of 2.1 and heats water from 15°C to 50°C. Hot water use is 100 liters per day, 365 days/yr. The electricity cost is $0.10/kWh. What is the annual water heating cost? (The specific heat of water (C) is 4.2 kJ/kg-°C.)
