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What about solar mass ?
Traditionally, a solar home is designed with a mass characteristic
to accompany passive solar construction. If you are looking at this
section of the website, you already know that mass is put in place
to moderate heat gain during winter days, and to extend the warmth
of the sun for a little while into the evening. Using "old solar"
technology and design technique, oversized windows or even sliding
glass doors would be lined up facing south and the flooring in front
of these units would be made of brick or concrete. In many cases it
would be proposed that an operable insulation curtain be put in
place that could be opened during the day, and closed during the
night. From years of designing and building solar homes, we have
found that the requirement to live in a masonry and glass box that
has to be operated twice daily has not worked out well for some
homeowners. Many older passive solar homes are now fully carpeted,
fully draped, or even enclosed with solid walls in order to make
living spaces more inviting. Passive solar modifications to
lifestyle are aimed at the heating season. In the mid-Atlantic, we
are finding that it may make more sense to focus more on efficient
cooling rather than near optimal passive solar heating. Our
designs use a "passive tempered" approach. We maximize our window
units on the South side, and calculate the height of those windows
so that the roof overhang will shade them as fully as possible
during the warmer months. We have no South facing windows that are
not shaded. Since our South facing glass does not go the floor, the
interior wall space on those walls is available for lifestyle
choices, such as furniture placement. As is requisite of passive
design, we adhere to maximizing living spaces on the South, and
concentrating storage areas, garages, and sleeping quarters on the
North. In the winter, the home warms up quickly as the Sun's heat
radiates through the South facing windows, and the central heating
system operates for a shorter period of time. Integral to "new
solar" design are the advances in efficiency envelope construction
we are currently using. By using very high quality window and door
units, sealed crawl spaces, cool attics, and super sealed blown foam
insulation, lowered solar heat gain will have its maximum effect,
and the homes' cooling systems will perform much better. One of the
greatest benefits of the passive tempered home is day lighting.
During sunlight hours, the interior spaces of the home are flooded
with natural sunlight, and the need to operate electric lighting is
greatly reduced. It makes for a very nice place to spend the day !
A final work on mass - If a home owner wants to have a mass
characteristic in their residence, our designs lend themselves to
such construction and it can be easily added. It won't hurt
anything, and it will enhance the passive solar heat cycle to some
extent.
Is geothermal heating an option, and how does it work?
Geothermal heating systems are electric
heat pumps that use a water loop for heat (and cool) btu transfer.
Water is circulated through a system of pipes which are put in
contact with the ground. Instead of pumping heat out of (or into)
the air, as in a standard heat pump system, heat is pumped out of
(or into ) the ground using the water as a transfer medium. We have
found that the best way to achieve ground contact for the geothermal
loop is in a vertical drilled well, with multiple ground loops going
"up" and "down". The water in the loop contacts the ground, but is
sealed away from the sides of the well in geothermal piping. This is
called a "closed loop" system. Geothermal HVAC systems are more
efficient that air based systems. It is easier to transfer a btu in
and out of water than it is to transfer a btu in and out of air. The
ground is a more consistent heat source/ sink than is the air. We
offer geothermal heat and cool as an option. The cost of the systems
is measurably greater than air based heat pumps, and when placed in
envelopes that are as efficient as ours, the payback period for the
difference in cost might be long. It is, however, a better heating
and cooling system. Geothermal becomes a matter of choice and
budget.
Do you have gray water systems available?
Gray water systems
transfer non toxic waste water to areas that will have less impact
on the environment, and hopefully create a secondary use for the
water as it soaks back into the earth. A common use for gray water
is lawn watering. Bingham Ridge homes use private septic systems. An
impact on municipal water filtration and stream water quality will
not be made by introducing a gray water system to a home. To the
extent gray water will aid in agricultural activities, we will
design a system to meet a homeowner's specific needs, given
limitations placed on us by the County Health Department. In the
area of water conservation, we promote rain water catchment systems
wherever possible. By collecting rain water for garden and lawn
watering, we can conserve ground water supplies, and save the
electricity needed to pump water out of the ground.
Is solar energy used for radiant floor heating?
We heat water for
domestic usage using solar panels on the roof, and a storage tank
for a pre-heat cycle in the potable system. The water produced by
this system is quite hot. Radiant floor heat systems require a
moderate hot water supply (around 106 degrees) and a slow flow
directed through zoned loops. In many systems, these loops are cased
in a concrete floor. Radiant loops can be attached to the underside
of a joist floor system as well. This installation will generally
require a modification to the sealed crawl space design and
insulation envelope, as we do not want to heat the crawl space as a
primary zone. Using potable hot water as a source for radiant heat
presents some problems. If the radiant circulation system is not run
continuously, water in the loops can be stagnate. These issues can
be overcome, but it may be best to supply a discrete heat source for
a radiant heating system. An issue to remember is that radiant
heating will supply heat only. You will still need a forced air
system for cooling. Radiant heat in the winter is very pleasant. The
floor is warm, and there are no fans blowing. As is the case with
geothermal, it will raise the cost of the residence. As an addition
to our base criteria, it can be nice. For some, it may mandate
living on a concrete floor instead of wood. It all becomes a matter
of choice and cost.
Should I use an 18 SEER or higher AC system?
The higher the SEER rating for a heat pump
system, the more efficient and quiet it will be. The jump in cost
from 13 SEER to 18 SEER is significant. By focusing our design on
sealed envelopes, sealed crawl spaces, cool attics, and good window
and door units, the pay back period for the difference in cost
between a 13 SEER unit and an 18 SEER unit at today's energy costs
is fairly long. The higher SEER unit is arguably superior. Again, it
is a matter of budget and desire. |
