Increasing Home Energy Efficency
Energy-efficient homes
require less energy to perform household functions as homes that are
less energy-efficient. There are many adjustments that homeowners
can make to reduce the amount of energy required by their homes.
Why make your home
more energy-efficient?
- Federal, state, utility
and local jurisdictions' financial incentives, such as tax
breaks, are very advantageous in most parts of the U.S.
- It saves money. It
costs less to power a home that has been converted to be more
energy-efficient.
- It increases
indoor comfort levels.
- It reduces our
contributions to climate change. Many scientists now believe
that excessive energy consumption contributes
significantly to global warming.
- It reduces pollution.
Conventional power production introduces pollutants into the air
that find their way into the soil and water supplies.
Heating and Cooling
As much as half of the
energy used in homes goes toward heating and cooling. The following
are a few ways that energy bills can be reduced through adjustments
to the heating and cooling systems:
- Add insulation to the
building envelope (walls, floors and ceiling) to bring the home
up to the U.S. Department of Energy (DOE)-recommended limits for
the climate zone in which the home is located.
- Insulate heating ducts.
Up to 40% of energy can be lost in uninsulated heating ducts
routed through unheated space. This means that up to 45 cents of
every dollar spent on heating can be wasted.
- Install a ceiling fan.
Ceiling fans can be used in place of air conditioners, which
require large amounts of energy.
- Periodically replace
air filters in air conditioners and heaters.
- Set thermostats to an
appropriate temperature. Specifically, they should be turned
down at night and when no one is home. In most homes, about 2%
of the heating bill will be saved for each degree that the
thermostat is lowered for at least eight hours each day. Turning
down the thermostat from 75°F to 70°F, for example, saves about
10% on heating costs.
- Install a programmable
thermostat. A programmable thermostat saves money by allowing
heating and cooling appliances to be automatically turned down
during times at which no one is home and at night. Programmable
thermostats contain no mercury and, in some climate zones, can
save up to $150 per year in energy costs.
- Install a wood stoves
or a pellet stove. These are more efficient sources of heat than
furnaces.
- At night, curtains
drawn over windows will better insulate the room.
Appliances and
Electronics
Appliances and electronics
are responsible for about 20% of household energy bills in a typical
U.S. home. The following are tips that will reduce the required
energy of electronics and appliances:
- Refrigerators and
freezers should not be located near the stove, dishwasher or
heat vents, or exposed to direct sunlight. Exposure to warm
areas will force them to use more energy to remain cool.
- Computers should be
shut off when not in use. If unattended computers must be left
on, their monitors should be shut off. According to some
studies, computers account for approximately 3% of all energy
consumption in the United States.
- Use efficient “Energy
Star” -ated appliances and electronics. These devices, approved
by the DOE and the EPA’s Energy Star program, range from TVs,
home theater systems, DVD players, CD players, receivers,
speakers and more. According to the EPA, if just 10% of homes
used energy-efficient appliances, it would reduce carbon
emissions by the equivalent of 1.7 million acres of trees.
- Chargers, such as those
for laptops and cell phones, consume energy when they are
plugged in. When they are not connected to electronics, chargers
should be unplugged.
- Laptop computers
consume considerably less electricity than desktop computers.
Electric Lighting

The average household
dedicates 11% of its energy budget to lighting. Traditional
incandescent lights convert approximately only 10% of the energy
that they consume into light, while the rest becomes heat. The use
of new lighting technologies, such as light-emitting diodes (LEDs)
and compact fluorescent lamps (CFL), can reduce energy use required
by lighting by 50% to 75%. Advances in lighting controls offer
further energy savings by reducing the amount of time lights are on
but not being used. Here are some facts about CFLs and LEDs:
- CFLs use 75% less
energy and last about 10 times longer than traditional
incandescent bulbs.
- LEDs last even longer
than CFLs and consume less energy.
- LEDs have no moving
parts and, unlike CFLs, they contain no mercury
Daylighting
Daylighting is the practice
of using natural light to illuminate the home's interior. It can be
achieved using the following approaches:
- skylights. It’s
important that they be double-pane or they may not be
cost-effective. Flashing skylights correctly is key to avoiding
leaks.
- light shelves. Light
shelves are passive devices designed to bounce light deep into a
building. They may be interior or exterior. Light shelves can
introduce light into a space up to 2½ times the distance from
the floor to the top of the window, and advanced light shelves
may introduce four times that amount.
- clerestory windows.
Clerestory windows are short, wide windows set high on the
wall. Protected from the summer sun by the roof overhang, they
allow winter sun to shine through for natural lighting and
warmth.
- light tubes. Light
tubes use a special lens designed to amplify low-level light and
reduce light intensity from the midday sun. Sunlight is
channeled through a tube coated with a highly relective
material, then enters the living space through a diffuser
designed to distribute light evenly.
Cooking
An enormous amount of energy
is wasted while cooking. The following recommendations and
statistics illustrate less wasteful ways of cooking:
- Convection ovens are
more efficient that conventional ovens. They use fans to force
hot air to circulate more evenly, thereby allowing food to be
cooked at a lower temperature. Convection ovens use
approximately 20% less electricity than conventional ovens.
- Microwave ovens consume
approximately 80% less energy than conventional ovens.
- Pans should be placed
on the correctly-sized heating element or flame.
- Lids make food heat
more quickly than pans that do not have lids.
- Pressure cookers reduce
cooking time dramatically.
- When using conventional
ovens, food should be placed on the top rack. The top rack is
hotter and will cook food faster.
Leakage Through the Building Envelope
Sealing holes and cracks in
the home’s envelope helps reduce drafts, moisture, dust, pollen and
noise. A tightly sealed home can improve comfort and indoor air
quality while reducing utility bills. Tightening the home reduces
the number of air changes per hour. The following are some common
places where leakage may occur:
- electrical outlets;
- mail slots;
- around pipes and wires;
- wall- or window-mounted
air conditioners;
- attic hatches;
- fireplace dampers;
- weatherstripping around
doors;
- baseboards;
- window frames; and
- switch plates.
Strategies for filling
cracks:
- Caulk can be used to
fill small gaps. Caulk can be obtained at hardware stores.
- Expandable foam can be
used to fill larger gaps.
- Foam gaskets can be
used to seal electrical outlets.
Windows and Doors
About one-third of the
home's total heat loss usually occurs through windows and doors. The
following are ways to reduce energy lost through doors and windows.
- Seal all window edges
and cracks with rope caulk. This is the cheapest and simplest
option.
- Windows can be
weatherstripped with a special lining that is inserted between
the window and the frame. For doors, weatherstrip around the
whole perimeter to ensure a tight seal when closed. Install
quality door sweeps on the bottom of the doors, if they aren't
already in place.
- Install storm windows
at windows with only single panes. A removable glass frame can
be installed over an existing window.
- If existing windows
have rotted or damaged wood, cracked glass, missing putty,
poorly fitting sashes, or locks that don't work, they should be
repaired or replaced.
Indoor Water
Conservation
The following systems can be
installed to conserve water usage in homes:
- low-flow
showerheads. They are available in different flow rates, and
some have a pause button which shuts off the water while the
bather lathers up.
- low-flow toilets.
Toilets consume 30% to 40% of the total water used in homes,
making them the biggest water users. Replacing an older
3.5-gallon toilet with a modern, low-flow 1.6-gallon toilet
can reduce usage an average of two gallons-per-flush (GPF),
saving 12,000 gallons of water per year. Low-flow toilets
usually have "1.6 GPF" marked on the bowl behind the seat or
inside the tank.
- vacuum-assist
toilets. These types of toilets have a vacuum chamber, which
uses a siphon action to suck air from the trap beneath the bowl,
allowing it to quickly fill with water to clear waste. Vacuum
toilets are relatively quiet.
- dual-flush toilets.
Dual-flush toilets have been used in Europe and Australia for
years, and are now gaining in popularity in the U.S. Dual-flush
toilets let you choose between a 1-gallon (or less) flush for
liquid waste, and a 1.6-gallon flush for solid waste. Dual-flush
1.6-GPF toilets reduce water consumption by an additional 30%.
Solar-Thermal
Heating
Solar water heating first
became popular in the 1970s when federal, state and utility
incentives encouraged their installation, as is happening again now.
Inspectors will see many of these older systems still in place but
no longer working. In practice, inspectors will encounter a wide
variety of system configurations and components, and recommending a
specialist inspection is a good idea in order to pass on liability.
These systems can be expensive. The idea is fairly simple. Solar
insulation heats a circulating fluid which transfers its heat to a
storage tank from which home hot water can be drawn, either directly
to plumbing fixtures, or to supply pre-heated water to boilers or
hot water heaters.
Various types of solar-thermal heating can be installed, such as:
- evacuated tube
collectors;
- flat-plate collectors;
and
- parabolic
through-collectors.
In summary, there are a
variety of adjustments to the home that homeowners can make to
increase the energy-efficiency of their homes.
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