Energy Solutions: Conservation and Efficiency 459
Excellent insulation
throughout walls, floors,
and roof; almost airtight
Few or no windows
on north, east, and
west sides
No large furnace
Concrete foundation
Air-to-air heat
exchanger
provides
ventilation to
improve air
quality.
Small,
south-facing
windows with
insulating
glass
Ontario Power Generation
b. A superinsulated office building in Toronto, Canada, has
south-facing windows with insulating glass. The building is so
well insulated it uses no furnace.
a. A superinsulated home is so well insulated and airtight
that it doesn’t require a furnace in winter. Heat from the
inhabitants, light bulbs, and appliances provides most or all
the necessary heat.
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How old is the refrigerator that you most
often use? How much energy would you save each year by
replacing it with a recent model?
Think Critically
The National Appliance Energy Conservation Act
(NAECA) sets national appliance efficiency standards for
refrigerators, freezers, washing machines, clothes dryers,
dishwashers, room air conditioners, and ranges and ovens
(including microwaves). For example, refrigerators built
today consume 80 percent less energy than comparable
models built in the early 1970s (}ÕÀiÊ£n°£{).
Energy costs often account for 30 percent of a com-
pany’s operating budget. It makes good economic sense
for businesses in older buildings to invest in energy im-
provements, which often pay for themselves in a few years.
Implementing energy improvements may be as simple as
fine-tuning existing heating, ventilation, and air condi-
tioning systems or as major as replacing all the windows
and lights. Both the environment and a company’s bot-
tom line can benefit from any energy improvements.
Automobile efficiency has improved dramatically
since the mid-1970s as a result of the use of lighter
materials and designs that reduce air drag. The aver-
age fuel efficiency of new passenger cars doubled be-
tween the mid-1970s and the mid-1980s. It declined after
0
200
400
600
800
1000
1200
1400
1600
1800
2000
Energy use per household (kWh/year)^197219781984
Year
1990 1994 2000 2004 2012
Based on data from Association of HomeAppliance Manufacturers (2011).
Energy use standard for new refrigerators,
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Refrigerators sold today are four times as efficient as those sold in
the early 1970s. Advances in insulation, coolant, and compressor
technologies have all contributed to this improvement.
Refrigerators today are also less expensive and more reliable.