42 terms


Department of Energy
Heat Pumps Provide higher or lower savings than water heaters?
Higher savings
Leaking faucets can increase your energy costs (T/F)
Insulating the cold water pipes will save a lot of E
Insulating hot water pipes saves E
Refrigerators are ______ _______
Heat movers
Horizontal axis (front loading) washing machines are more effiencent than
top loading machines
What kind of label do highly energy efficient appliances have?
Energy Star Label
Water heaters are set to _____ degrees F
A water heater heats 151 gal of water from 54oF to 137oF every day. What is the annual energy requirement of the water heater
Annual energy requirement = 151 (137 - 54) 8.3 * 365 = 37968723.5 BTUs. Note: 1 gal of water weighs 8.3 lbs.
An old refrigerator consumes 250 W of power. Assuming that the refrigerator operates for 18 hours everyday, what is the annual operating cost of the refrigerator, if the cost of electricity is $0.06 per kWh?
Annual operating cost = 250 / 1000 18 0.06 * 365 = $98.55.
Which one of the following is true about global temperatures in the last century
iincreased about 1 degree fahrenheit
How many tons of carbon dioxide are released into the air each year
7 billions tons
global climate change caused by
increase in concentration of greenhouse gases in atmosphere due to human activities
condition that contributes to acid rain damage
poor soil buffering capacity
which area of US has most acidic rain
Where is ozone typically at its greatest concentrations
high altitudes
needed to produce ground level ozone
NOx, Hydrocarbons, SO2, sunlight
stratosphere begins at what altitude
10 miles
secondary pollutants
primary pollutants
PM2.5 describes the "fine" particles that are _____ 2.5 µm (micro meter) in diameter
PM2.5 describes the "fine" particles that are smaller than or equal to 2.5 µm (micro meter) in diameter.
Type R lamps
replaced 120 Watt Incadescent (800 hours) ($0.67) with with 28 (8000 hours) ($5.71) CFL
Compact floursecent lamps ____ times more efficent thatn incadescent lamps
Use of modern technology can reduce lighting by
Flourescent light is produced by
converting UV into visible light
reguires ballast
higher CRI
better color rendering
kitchen - 5 by 10
50 footcandles of illumination
how many 40 watt bulbs if one emits 500 lumens
5*10 = 50
lumens required: 50*50= 2500
2500/ 500 = 5 bulbs
HPS lamp
outdoor and industrial applications
120-watt light bulb left on for 24 hours
how much to operate light bulb if electricity costs 6 cents per Kwh
E consumed = 120/1000*24 = 2.88
E cost = 2.88 * 6/100 = $0.1728
100 watt
incandescent light bulb is operated for 12 hours
15 watt fluorescent light
10 cents per kWh, cost savings
100/1000*12=1.2 kWh
1.2*10/100 = 0.12
Vapors of which element are used to fill energy efficient bulbs
footcandle is calculated as
fc = lumens of light/ area in sq. ft
Incadescent lights operate at _____ than flurosecent light
Higher wattage bulbs have ________ efficiency compared to lower wattage bulbs
efficacy of lighting is measured by
lumens per watt
198 W, 15 h./day, $0.11
198/ 1000150.11*365 = $119.245
dishwashers require water temp of
212 W, 18 hr/ day, $0.09
212/1000 18 0.09 * 365 = 125.95
on-demand water heaters
do not have a storage tank
natural gas water heaters cost more to install than
heat pump
more efficient for heating water
higher savings than conventional water heaters