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You Can Go a Long Way Toward a Zero Energy Home
We need to face it... changing a few light bulbs ain't gonna
do it. Reducing your energy use a few percent still means you are
generating a lot of damage to the environment.
We need to start thinking in terms of moving toward ZERO
impact. We don't have the luxury of risking "what if we make a few
little changes in our lifestyle", and hope that's enough. Six billion
people got us into the situation were in. Six billion people cutting
their energy use a few percent isn't enough. What we do or fail to do
will create the quality of life for children in future generations. The
stakes are too high to take the situation lightly. We need BIG
lifestyle changes.
It's possible to make a home that uses no energy other than
what it cleanly makes from the sun or wind, or energy exchanged with
the ground. True, it's not cheap. But what makes sense is to take a
look at the technologies available and incorporate those that are
reasonably achievable now. Then, each year, do a reassessment. The
field of energy efficiency is growing fast. There will surely be lots
of new technologies and products coming along in the next few years.
And the price of many energy savers that you can't afford now should
come down in the future. Over the course of the next five years, you
should be able to get much closer to a zero energy home (ZEH).
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This shows how important a single
item can be, such as your refrigerator or water heater. By
concentrating on key areas, it's possible to greatly reduce the energy
use in a home.
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Here's what a house that has greatly reduced energy use might
look like:
Clothes washer
Asko W6022 clothes washer using cold water for most
loads. The Asko is a phenomenal unit, using only 100 kWh per year. Some
washers use over 400 kWh per year, according to the ENERGY STAR
program. about $1200
Dishwasher
Asko, Bosch and Fisher & Paykel all have units
that are ENERGY STAR rated at around 190 kWh per year. This compares to
531 kWh/year for the least efficient model currently made.
Refrigerator
Sun Frost refrigerator. These use between 171-254
kWh/year, depending on the size, compared to over 700 kWh/year for the
less efficient units currently on the market. Older refrigerators use
as much as almost 2,000 kWh per year! And a unit that's using lots of
energy is also heating up your kitchen, increasing the load on the
cooling system (and making your home less comfortable).
sunfrost.com
Home Cooling
A central air condition with a seasonal efficiency rating
(SEER) of 20 or higher is used. Models include Carrier Infinity and
Lennox Signature Collection XC21. Additionally, south facing windows
would have window tinting designed to reduce heat gain in the
home. Either window awnings are used or shade trees are
planted to minimize direct sunlight coming through the windows during
the summer months. Ceiling fans are used in most rooms. A programmable
thermostat is used. Warm Window Insulated Shades (or
similar insulated shades with a good air seal) are used. These reduce
heat loss through windows making any room comfortable all year long, as
well as reduce outside noise.
ceiling fans ~$100-400 per fan
programmable thermostat: $30-100
window tinting: ~$100-200
gilafilms.com
Warm Window Insulated
Shade System how
they work
Roof
The roof is light in color, to reduce heat build up
in the house during the summer. A radiant barrier is used in
the attic to reduce heat build up in the attic.
Radiant Guard
$100-200 (for materials)
Computer(s)
The Everex StepNote
NC1501 is claimed to be most energy
efficient notebook PC in the world. It uses only 12 watts of peak
power. A desktop computer and monitor can typically use between 140-230
watts. Additionally, a TV tuner card can be plugged into the USB port.
This makes an extremely efficient TV set. Hauppauge even makes a TV
tuner for computers with remote control.
TVs
TV size is limited to 20-26 inches. A typical 20 flat screen,
such as from Sharp, uses about 60 watts. A 26 inch uses 120 watts. The
large screen sets use as much as 610 watts, over 10 times more than a
20 inch model.
Hot water
An evacuated tube water heating system is used.
These work better on cloudy days than older types. This is augmented by
a tankless, on demand water heater. Additionally, 1.5 gallon
per minute (GPM) shower heads, such as the Jet-Stream Showerhead, are
used. Faucet aerators are used on sink faucets. Hot water pipes are
insulated.
shower head: ~$30 each
pipe insulation ~$50-100 (materials)
Lighting
A blend of lighting is used. Solar tubes are used to
"pipe" sunlight into the house. These make a cheerier, more pleasant
room. LED lighting is used in the most frequently used
locations. LED lights are more efficient than fluorescents and generate
almost no heat, reducing cooling costs. Compact fluorescent bulbs
are used in areas where lights aren't on a lot.
C.
Crane's LED lights
solatube.com
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A
solar tube, shown in these before and after images, give free natural
light with no energy use. Different diameter tubes are available. This
one is from Solatube.

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Heating
Geothermal heat can pay for itself in a few years. If it's
used, it is usually used to heat the homes water, too. Unfortunately,
these systems haven't caught on well, despite their great merits. An
alternative is the use of Solarsheat. These are panels on the
roof or outside of walls. They capture heat from the sun and bring it
into the house with small fans powered by solar cells. Solarsheats can
either be used individually, to heat one room, or they may be used to
distribute heated air to the entire home. Panels can be mounted on the
roof, with the heated air ducted to the cool air intake of the
conventional furnace. In a 2,000 square foot house, typically either
four or five SolarSheat panels would be used. (pdf graphic
of the SolarSheat Furnace Retrofit Pak) Additionally, specific
rooms can be heated with radiant heat either under carpet or
under the wood floors. This lets the home owner keep one room, such as
a bedroom, comfortable, while the rest of the house is cooler.
more about Solarsheat
Geothermal Resources Council
Electric power
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image
credit: SCHOTT AG
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Solar photovoltaic (PV) panels are used to generate
electricity. Interestingly, all the above technologies probably give a
greater return on the investment than solar panels. So it makes sense
to reduce the demand for electricity as much as possible, first. Then
use a PV system sized to meet the demand of the home.
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For an existing home, there's a lot you can do to reduce it's
environmental impact. You can use these technologies to get closer to
having a zero energy home. Just think how much you can increase your
home's resale value!
You can learn more about near zero energy homes at sites like:
builditsolar.com Half Plan (cut your energy use in half)
Independence
Energy Homes
zeroenergyhomedallas.com
Clarum Homes
Aug. 2007
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