EGEE 102 – Energy Conservation
And Environmental Protection
Appliances
Energy Consumption for
Appliances (1997)
• 1192 Billion kWh total residential use
• 134 Billion kWh for refrigerators
($12.14 Billion)
• 549 Billion kWh for other
appliances and lighting (48.44)
EGEE 102 - Pisupati
2
Water Heater
$288.00
Freezer/Frostless $136.80
Refrigerator
$118.80
Waterbed
$86.40
House Lighting $72.00
Clothes Dryer
$59.76
Electric Range
$45.36
Dishwasher
$23.04
EGEE 102 - Pisupati
3
Energy Guides
• EnergyGuide labels be placed on all new
refrigerators, freezers, water heaters,
dishwashers, clothes washers, room air
conditioners, heat pumps, furnaces, and
boilers.
• EnergyGuide labels show the estimated
yearly electricity consumption to operate
the product along with a scale for
comparison among similar products
EGEE 102 - Pisupati
4
Energy Guide
• What is it ?
• How to use it?
• See class
worksheet
EGEE 102 - Pisupati
5
Water Heaters
• Water heating is the third
largest energy expense in
your home. It typically
accounts for about 14% of
your utility bill.
• A family of four, each
showering for 5 minutes a
day, uses 700 gallons of
water a week; this is enough
for a 3-year supply of
drinking water for one
EGEE 102 - Pisupati
person.
6
Heat Transfer
• Heat transfer is proportional to the
temperature difference
• I.e. 120F – 50 F (ambient
temperature)
• Whether we use water or not heat
is continuously flowing from the
pipes to the room
EGEE 102 - Pisupati
7
Energy Required to heat
Water
• Q= m x Cp x (Temperature
Difference)
•
•
•
•
•
•
M= mass
Cp= Heat capacity (1 Btu/lb.F)
700 gal/wk x 8.3 lb/gal x (120-56)
=371840 Btus
=109 kWh/wk or 5667 kWh per year
$385
EGEE 102 - Pisupati
8
Storage Tank Water
Heaters
• When you turn on
a hot water faucet
or use hot water in
a dishwasher or
clothes washer,
water pipes draw
hot water from the
tank.
EGEE 102 - Pisupati
9
Electric vs. Gas
• Electric water heaters are generally
less expensive to install than gasfired types because they don't
require venting. But unless you live
in a region where electricity is
unusually affordable, an electric
water heater can be significantly
more expensive to operate.
EGEE 102 - Pisupati
10
Energy Savings-Water
Heaters
• REDUCE WATER TEMPERATURE
•
Recall that heat flow is a function
of DT
• If T = 100°F, this is adequate for
clothes washing and bathing.
• T = 100°F may be too low for
satisfactory operation of some
dishwashers. (But some new
models of dishwashers may supply
auxiliary heat to the water.)
EGEE 102 - Pisupati
11
Energy Saving-Water
Heaters
•
INSULATE WATER TANK (AND
HOT WATER PIPES)
• Substantial saving in monthly
energy bill by double layer of
fiberglass insulation on water
tank.
• The heat loss from the water tank
contributes to space heating ?!
• Depends on design of home and
location of water tank.
EGEE 102 - Pisupati
12
Energy Savings - Water
Heaters
•
REDUCE CONSUMPTION
•
•
•
Flow restricting heads for
showers, sinks
Shut off water heater at certain
times
AUXILIARY SOURCES OF HOT
WATER
•
Sometimes one can install a heat
exchanger
in flue of furnace or 13
EGEE 102 - Pisupati
auxiliary wood burner
On-Demand Water
Heaters
•
•
•
•
Hot water never runs out (low demand)
Will not leak or rupture
Reduce water heating costs as much as 20-30%
Heats only the water you use, at the temperature
you desire Cold water is not required to regulate
temperature
• Maintains its 99.5% efficiency throughout its
lifespan
• Average lifespan is 20 years vs. a 10 year
lifespan for a standard tank heater Scaling and
rusting will not occur Hot water, forever!
EGEE 102 - Pisupati
14
Operating Principle
EGEE 102 - Pisupati
One of the most
powerful electric
tankless water
heaters on the
market,
this 22KW, four
element water heater
is configured for cold
climates
where the incoming
water temperature
can drop below 50° F.
http://www.e-tankless.com/products.php
15
Type of Solar Water
Heaters
• Active Systems
• Open-Loop Active Systems
• Closed-Loop Active Systems
• Passive Systems
• Thermo-Siphon Systems
Batch Heaters
Heart of all solar heating systems: SOLAR COLECTOR!!!
EGEE 102 - Pisupati
16
Solar Collectors
• flat-plate,
• evacuated-tube and
• concentrating.
EGEE 102 - Pisupati
17
Evacuated Tube
Collector
EGEE 102 - Pisupati
18
Factors for sizing a
Solar Collector
• Your local annual average solar insolation level.
• Average daily hot water usage volume
• Daily hot water usage pattern (mostly mornings,
mostly evenings)
• Average mains water temperature
• Annually/daily shade patterns
• Angle/direction of installation (a less than ideal
angle will reduce efficiency)
• Installation site (Do you have enough room for 2+
collectors?)
EGEE 102 - Pisupati
19
Solar Water Heater
• A thermosyphon-type
solar water heater has an
insulated water storage
tank mounted above flat
plate solar collectors
• The collectors transfer
heat from the sun to an
antifreeze collector fluid.
• Whenever hot water is
used, solar heated water
is drawn from the storage
tank into the electric
water heater
Is this activeEGEE
or passive
system?
102 - Pisupati
20
http://energyoutlet.com/res/waterheat/thermosyphon.gif
Solar Heating
• http://www.focussolar.com/index.ht
m
• http://www.focussolar.com/insolatio
n.htm
EGEE 102 - Pisupati
21
http://www.warmwater.com/eco.htm
Refrigerator
• Heat Mover
• COP
High Temperature Reservoir
Work
Low temperature
Reservoir
EGEE 102 - Pisupati
22
Components of a
Refrigerator
• There are five basic parts to any refrigerator
• Compressor
• Heat-exchanging pipes - serpentine or coiled set
of pipes outside the unit
• Expansion valve
• Heat-exchanging pipes - serpentine or coiled set
of pipes inside the unit
• Refrigerant - liquid that evaporates inside the
refrigerator to create the cold temperatures
EGEE 102 - Pisupati
23
How a Refrigerator
Works?
The compressor compresses the ammonia
gas. The compressed gas heats up as it
is pressurized .
• The coils on the back of the refrigerator
let the hot ammonia gas dissipate its
heat. The ammonia gas condenses into
ammonia liquid at high pressure.
• The high-pressure ammonia liquid flows
through the expansion valve.
• The liquid ammonia immediately boils
and vaporizes (light blue), its
temperature dropping to -27 F. This
makes the inside of the refrigerator cold.
• The cold ammonia gas is sucked up by
the compressor, and the cycle repeats.
EGEE 102 - Pisupati
Ammonia boils at -27F
24
Gas and Propane
Refrigerator
EGEE 102 - Pisupati
25
Energy Efficiency
• Federal efficiency standards took
effect in 1993, requiring new
refrigerators to be more efficient
than ever before.
• The energy bill for a typical new
refrigerator with automatic defrost
and top-mounted freezer will be
about $55/year, whereas a typical
model sold inEGEE
1973
will cost nearly
102 - Pisupati
26
Why Buy An Energy
Efficient Refrigerator?
• Uses the most electricity of all your
kitchen appliances and accounts for as
much as 15 percent of a home's total
energy usage.
• A typical refrigerator costs about $1,140
to operate over its lifetime.
• Refrigerators made to meet the latest
DOE standards (which will take effect in
2001) will cut consumers' energy costs by
30 percent compared to the previous
EGEE 102 - Pisupati
27
(1993) standards.
Side-by-side
• Consumes more
energy
EGEE 102 - Pisupati
28
Top Mounted Type
• More efficientconsumes less
energy (13%) than
side by side design
EGEE 102 - Pisupati
29
Efficiency of a
Refrigerator
• The efficiency of a refrigerator is
expressed in "volume cooled per
unit electric energy per day."
Volume is measured in cubic feet
and electrical energy is measured in
kilowatthours
EGEE 102 - Pisupati
30
EGEE 102New
- Pisupati
31
Efficiency of an Average
Refrigerator in the United
States
Technology
improvements
• addition of vacuum insulation panels
around freezer section to reduce heat
transfer,
• addition of polyurethane foam to the
doors to double insulation thickness,
• replacement of AC motors with more
efficient DC motors, and
• replacement of automatic defrost control
with an adaptive defrost that operates
only when needed
EGEE 102 - Pisupati
32
Fridge of the Future
• uses half as much
energy as today's
refrigeratorfreezers (RFs) and
one-fifth as much
as 1972 models:
the 1 kilowatt-hour
per day
refrigerator.
EGEE 102 - Pisupati
http://www.ornl.gov/ORNL/BTC/adv-rf-tech.htm
33
Energy Savings
• Cuts power consumption to 0.93
kWh/day, a performance that
exceeds the 2001 energy standard
and that would save $6.5 billion
annually if all the 125 million RFs in
the U.S. operated as efficiently
EGEE 102 - Pisupati
34
Good Operating
Practices
• Don't put the refrigerator near a heat source - an
oven, the dishwasher or direct sunlight from a
window.
• Make sure air can circulate around the
condenser coils. Leave a space between the wall
or cabinets.
• Keep your refrigerator's coils clean. Brushing or
vacuuming the coils can improve efficiency by as
much as 30 percent.
• Check door seals to make sure they are airtight.
To test them, close the door on a dollar bill and
try to pull it out. If the dollar slides out easily,
kiss that dollar away because you're wasting
energy and money by letting cold air leak out!
EGEE 102 - Pisupati
35
• Check the temperature - a fridge that is 10
degrees colder than necessary can use
25 percent more energy. Refrigerators
should be kept between 35 and 38
degrees - freezers at 0 degrees
Fahrenheit.
A full refrigerator retains cold better than
an empty one.
• Open the door as little as possible. Get in
and out quickly.
EGEE 102 - Pisupati
36
• Regularly defrost manual-defrost models.
Frost buildup increases the amount of
energy needed to keep the motor running.
• Allow hot foods to cool before
refrigerating or freezing.
• Get rid of that older, energy-hogging
second refrigerator in your garage! One
large refrigerator is cheaper to run than
two smaller ones.
EGEE 102 - Pisupati
37
Clothes Washers
• There are two designs:
• top-loading
• front-loading.
• A typical household does nearly 400
loads of laundry per year, using
about 40 gallons of water per full
load with a conventional washer
EGEE 102 - Pisupati
38
Why Energy Efficient
Models?
• You could save as much as 7,000
gallons of water per year.
• You are saving all the energy that
would have been needed to heat that
water.
• This adds up to savings for you and a
big boost for the environment.
EGEE 102 - Pisupati
39
How are they Energy
Efficient?
• Top loading horizontal-axis or tumbleaction machines repeatedly lift and drop
clothes, instead of moving clothes around
a central axis.
• Top-loading washers use sensor
technology to closely control the
incoming water temperature. To reduce
water consumption, they spray clothes
with repeated high-pressure rinses to
remove soap residues rather than soaking
them in a full tub of rinse water.
EGEE 102 - Pisupati
40
Energy Star Washers
• A full-size ENERGY STAR® clothes
washer uses 20-25 gallons per load
• Nearly 50 percent less water and 30%40% less energy used per load
• Washer design causes less wear and tear
on clothes
• Bulky items such as blankets fit easily in
the super capacity basket.
• Better water extraction means less dryer
time, for further energy savings
EGEE 102 - Pisupati
41
• washers are most efficient when
they are fully loaded
EGEE 102 - Pisupati
42
Dishwashers- Features
• Child-safety locks
• Construction materials
• Cycles and temperature
settings
• Energy use
• Controls
•
•
•
•
Countdown timer
Clean light
Soil sensors
Delay-start
EGEE 102 - Pisupati
43
Types of Dishwashers
• Built in Type
• Portable dishwashers
EGEE 102 - Pisupati
44
Operation Principle
EGEE 102 - Pisupati
45
Energy Efficiency
EGEE 102 - Pisupati
46
Dish Washers
• ENERGY STAR® dishwashers save
electricity and hot water by using both
improved technology for the primary wash
cycle, and by using less hot water to
clean.
• Construction includes energy efficient
motors, and other advanced technology
such as sensors that determine the length
of the washing cycle and the temperature
of the water necessary
to clean the
EGEE 102 - Pisupati
47
dishes.