2005 Parade
of Homes
2006 APEX Award
for Energy Efficiency!
Based on $0.065
per kilowatt, this 2412 square foot home has a projected
power usage of $3 per day ($92 per month) with $1.50 of it
being for home comfort (heat/air) and hot water. During the
2005 Parade Of Homes, set at 70 degrees, the total
electrical usage for this home was $94. WaterFurnace
Geothermal heating/cooling, Icynene Spray Foam, and Tempra
tankless water heating system makes this possible.
Air Conditioning &
Heating:
The
vision for this project was to design a home with comfort as
the primary goal.
We selected a
three ton, two-stage WaterFurnace E Series geothermal system
carrying the EPA Energy Star Rating. According to the EPA,
geothermal systems are the most energy efficient,
environmentally clean, and cost-effective space conditioning
systems available (source: "Space Conditioning: The Next
Frontier," EPA 430-R-93-004, April 1993). As an extra bonus,
no outside air conditioner is required which makes for a
very aesthetically pleasing landscape with no noisy outside
unit.
Adding Zone Control....
For
added comfort and efficiency, four zones were designed into
the home comfort system. The gym, master suite, living area,
and bedrooms all have their own fully programmable
touchscreen thermostat. All thermostats are located in the
rear hallway with low profile sensors in the zoning area. In
addition, every zoned area/room has its own return air
system to assure no hot spots in the home. The end result is
less than 1 degree difference in temperature anywhere in the
home.
Insulation:
Applied
as a liquid, Icynene expands to 100 times its volume in
seconds to fill every crack and crevice while remaining
flexible so that the integrity of the building envelope seal
remains intact over time. Icynene's spray formula has an
R-value of 3.6 per inch. It acts as a complete insulation
and air barrier to minimize air leakage and seal the
building envelope for optimal air tightness. The end result
is a super tight home with air exchange rates roughly one
third of the standard home built today. According to the
Minneapolis Blower Door, Inc. testing, the estimated cost of
air leakage for heating/cooling in this home is $20.....a
year! As an added bonus, since the Icynene Spray Foam is
applied directly to the roof line and doesn't allow outside
air to enter the structure, the entire attic space above the
living area is only 4 degrees warmer than the home and can
be used as storage space.
Hot Water:
Tempra Tankless Water Heater provides unlimited supply of
hot water. The system comes with a convenient electric
temperature control on the front of it.
Electric and
gas tank type water heaters are subject to stand-by losses
which amount to 15 - 20% of the power/gas used. To maximize
efficiency, the waste heat off of the geothermal system is
stored in a 50 gallon tank which supplies the tankless
system. In many instances, the tankless system doesn't even
come on due to the free preheated water from the
geothermal.
PDF File
End Result:
A very efficient home that gained roughly 900 square foot of
usable semi conditioned attic space, virtually unlimited hot
water, extremely comfortable and even temperature rooms, and
a power bill any homeowner could afford. Total cost of these
upgrades was roughly 4% of total cost of home. So not only
is the house super quiet and extremely energy efficient,
based on the savings in power bill versus increased
mortgage, the higher standard of efficiency actually saves
money every month!
We'd like to
thank the following trade allies:
Monthly
statements from CHELCO:
07/28/05 - 912 KWH
08/25/05 - 1331 KWH
09/29/05 - 1825 KWH
10/27/05 - 1527 KWH
12/01/05 - 1370 KWH
12/29/05 - 1435 KWH
01/26/06 - 1684 KWH
02/24/06 - 1324 KWH
03/30/06 - 1516 KWH
04/27/06 - 1529 KWH
05/17/06 - 1607 KWH
06/19/06 - 2108 KWH
07/19/06 - 2047 KWH
08/17/06 - 1941 KWH
09/18/06 - 2131 KWH
10/18/06 - 1588 KWH
11/16/06 - 1278 KWH
12/18/06 - 1748 KWH
01/19/07 - 1941 KWH
02/15/07 - 1597 KWH
03/20/07 - 1726 KWH
04/17/07 - 1453 KWH
05/17/07 - 1722 KWH
06/20/07 - 1910 KWH
07/18/07 - 1785 KWH
08/17/07 - 2114 KWH
Average - 1660 KWH
Okay, so how
much does 1660 KWH cost?
At $0.065 per KHW - $107.90
At $0.070 per KHW - $116.20
At $0.075 per KHW - $124.50
At $0.080 per KHW - $132.80
At $0.085 per KHW - $141.10
At $0.090 per KHW - $149.40
At $0.095 per KHW - $157.70
At $0.100 per KHW - $166.00
At $0.105 per KHW - $174.30
At $0.110 per KHW - $182.60
At $0.115 per KHW - $190.90
At $0.120 per KHW - $199.20
At $0.125 per KHW - $207.50
At $0.130 per KHW - $215.80
At $0.135 per KHW - $224.10
According to a
2005 study by AEC, a 1500 square foot all electric home
averaged 1910 KWH. Up to April 2006, this home has averaged
1445 KWH. Or 60% more home with 75% the power bill
of a typical 1500 square foot all electric home. In 2007,
the home was using more electricity due to the extreme
summer heat (in the 100's for days at a time). Even then,
87% the power bill with 60% more home.
May 2006 Update:
Reviewing the
April statement, the actual power rate has been $0.07046
with a wholesale adjustment making the actual rate closer to
$0.090394 per KWH. What this means is the power bill using
1529 KWH is $138.21 instead of the projected $99.39 at
$0.065 or roughly a 39% increase! We anticipated a home
using conventional construction methods to easily be $190.
With the rate increases, it would be more like $264. Making
a positive cash flow plus getting the much, much higher
comfort, even temperatures in the home, no outside unit, 900
square foot of "free" storage space in the attic, longer
life expectancy of the geothermal, lower repair bills on the
air conditioner, unlimited hot water, extremely quiet home,
and higher resale value.
According to
some averages of homes in this neighborhood, the average
monthly usage was 2340 KWH and the homes averaged out to 300
square feet less. At $0.09 a KWH, that's $80.55 more
every month with less house!
What about
compared to natural gas in the winter time? Comparing
the heat performance of this system based on Okaloosa Gas
winter rates, this home would have cost almost 3 times
(293%) more to heat using gas without even
considering the benefit of free hot water assist. With the
new WaterFurnace Envision, it would have been well over 3
times (342%) to use natural gas to heat the home. In
addition, there aren't any penetrations for venting being
both unsightly and causing a higher infiltration rate.
Higher infiltration rate causes longer run times to
heat/cool the home (penetration equates to "required holes"
in our home) and more dust in the home. There are required
ventilation in homes such as the plumbing. However, the
plumbing stacks are minimum and into the septic system not
having an affect on infiltration. Bathroom exhaust fans and
clothes driers are vented to the outside but have a flapper
that closes when not in use.
(Pricing
information based on the gas rates published on Okaloosa
Gas'
website, the data
provided by WaterFurnace, and ARI ratings.)
Geothermal...pay a little more now, save a lot
more every month.
September 2006 Update:
We've got a
little over a year worth of utility bills and want to see
the savings using the programmable thermostats. These
intentionally weren't set so we could see a real house
study. So we programmed the thermostats to our lifestyle
and tweaked the geothermal zoning to give maximum savings
without sacrificing comfort.
Bedrooms are
set at 78F in Summer and 71F in Winter. The children were
complaining that 75, 76, & 77 was too cold. Because of
using water as the heat transfer, geothermal heating feels
warmer and geothermal cooling feels cooler than everyday
systems.
The main living
is set for 76F in Summer and 71F in Winter. In the previous
home using air source heat pumps, the temperature was
normally set at 74F in the Summer. 76F is quiet
comfortable.
The master
suite is set for 74F in Summer and 69F in Winter and the
Study/Gym is set for 80F in Summer and 65F in Winter. The
Study/Gym isn't being used other than for storage.
All the
settings above are based on current schedule of family
activities. When the zone isn't being occupied, the
temperature goes up or down approximately 3 degrees. The
exception is the Study/Gym which is set for a constant
80S/65W since it's never occupied.
