Here
Is A Crash Course in geothermal heat pumps!
Homeowners in virtually every region of the United States are
enjoying a high level of comfort and significantly reducing
their energy use today with geothermal heat pumps also called
geothermal ground contact heat exchange (geothermal) heating
and cooling.
This marvelous
technology relies primarily on the Earth's natural thermal
energy, a renewable resource, to heat or cool a house or multi-family
dwelling. The only additional energy geothermal ground contact
heat exchange systems require is the small amount of electricity
they employ to concentrate what Mother Nature provides and
then to circulate high-quality heating and cooling throughout
the home.
Homeowners who
use geothermal ground contact heat exchange systems give them
superior ratings because of their ability to deliver comfortably
warm air, even on the coldest winter days, and because of
their extraordinarily low operating costs. As an additional
benefit, geothermal ground contact heat exchange systems can
provide inexpensive hot water, either to supplement or replace
entirely the output of a conventional, domestic water heater.
Geothermal ground
contact heat exchange heating and cooling is cost effective
because it uses energy so efficiently.
This makes it
very environmentally friendly, too. For these reasons, federal
agencies like the Environmental Protection Agency and the
Department of Energy, as well as state agencies like the California
Energy Commission, endorse it.
Owners of geothermal
ground contact heat exchange systems can relax and enjoy high-quality
heating and cooling year after year. Geothermal ground contact
heat exchange systems work on a different principle than an
ordinary furnace/air conditioning system, and they require
little maintenance or attention from homeowners. Furnaces
must create heat by burning a fuel--typically natural gas,
propane, or fuel oil. With geothermal ground contact heat
exchange systems, there's no need to create heat, hence no
need for chemical combustion. Instead, the Earth's natural
heat is collected in winter through a series of pipes, called
a loop, installed below the surface of the ground or submersed
in a pond or lake. Fluid circulating in the loop carries this
heat to the home. An indoor geothermal ground contact heat
exchange system then uses electrically-driven compressors
and heat exchangers in a vapor compression cycle--the same
principle employed in a refrigerator--to concentrate the Earth's
energy and release it inside the home at a higher temperature.
In typical systems, duct fans distribute the heat to various
rooms. Geothermal ground contact heat exchange installed in
a basement or attic, and some are small enough to fit atop
a closet shelf. The indoor location also means the equipment
is protected from mechanical breakdowns that could result
from exposure to harsh Weather.
Geothermal ground
contact heat exchange works differently than conventional
heat pumps that use the outdoor air as both their heat source
or heat sink. Geothermal ground contact heat exchange systems
don't have to work as hard (which means they use less energy)
because they draw heat from a source whose temperature is
moderate. The temperature of the ground or groundwater a few
feet beneath the Earth's surface remains relatively constant
throughout the year, even though the outdoor air temperature
may fluctuate greatly with the change of seasons. At a depth
of approximately six feet, for example, the temperature of
soil in most of the world's regions remains stable between
45 F and 70 F. This is why well water drawn from below ground
tastes so cool even on the hottest summer days.
In winter, it's
much easier to capture heat from the soil at a moderate 50
º F. than from the atmosphere when the air temperature
is below zero. This is also why geothermal ground contact
heat exchange systems encounter no difficulty blowing comfortably
warm air through a home's ventilation system, even when the
outdoor air temperature is extremely cold.
Conversely, in
summer, the relatively cool ground absorbs a home's waste
heat more readily than the warm outdoor air.
In summer, the
process is reversed in order to cool the home. Excess heat
is drawn from the home, expelled to the loop, and absorbed
by the Earth. Geothermal ground contact heat exchange systems
provide cooling in the same way that a refrigerator keeps
its contents cool--by drawing heat from the interior, not
by injecting cold air.


Studies
show that approximately 70 percent of the energy used in a
geothermal ground contact heat exchange heating and cooling
system is renewable energy from the ground. The remainder
is clean, electrical energy which is employed to concentrate
heat and transport it from one location to another. In winter,
the ground soaks up solar energy and provides a barrier to
cold air. In summer, the ground heats up more slowly than
the outside air.
Ground
contact geothermal systems do the work that ordinarily requires
two appliances, a furnace and an air conditioner. They can
be located indoors because there's no need to exchange heat
with the outdoor air. They're so quiet homeowners don't even
realize they're on. They are also compact. Typically, they
are up to six times less expensive to operate since they are
far more efficient then any fossil fuel based system.
Making
Hot Water
Geothermal
ground contact heat exchange systems can also provide all
or part of a household's hot water. This can be highly economical,
especially if the home already has a geothermal ground contact
heat exchange system, hence a ground loop, in place.
One
economical way to obtain a portion of domestic hot water is
through the addition of a de-super-heater to the geothermal
ground contact heat exchange unit. A de-super-heater is a
small, auxiliary heat exchanger that uses superheated gases
from the heat pump's compressor to heat water. This hot water
then circulates through a pipe to the home's water heater
tank. In summer, when the geothermal ground contact heat exchange
system is in the cooling mode, the de-super-heater merely
uses excess heat that would otherwise be expelled to the loop.
When the geothermal ground contact heat exchange unit is running
frequently, homeowners can obtain all of their hot water in
this manner virtually for free. A conventional water heater
meets household hot water needs in winter if the de-super-heater
isn't producing enough, and in spring and fall when the geothermal
ground contact heat exchange system may not be operating at
all.

Because
geothermal ground contact heat exchange systems heat water
so efficiently, many manufacturers today are also offering
triple function geothermal ground contact heat exchange systems.
Triple function systems provide heating, cooling and hot water.
They use a separate heat exchanger to meet all of a household's
hot water needs.

The Earth Connection
Once
installed, the loop in a geothermal ground contact heat exchange
system remains out of sight beneath the Earth's surface while
it works unobtrusively to tap the heating and cooling nature
provides. The loop is made of a material that is extraordinarily
durable but which allows heat to pass through efficiently.
This is important so it doesn't retard the exchange of heat
between the Earth and the fluid in the loop. Loop manufacturers
typically use high-density polyethylene, a tough plastic.
When installers connect sections of pipe, they heat fuse the
joints. This makes the connections stronger than the pipe
itself. Some loop manufacturers offer up to 50-year warranties.
The fluid in the loop is water or an environmentally safe
antifreeze solution that circulates through the pipes in a
closed system.
Another
type of geothermal heating and cooling is Direct geothermal
ground contact heat exchange (DX) systems, which utilize copper
piping placed underground. As refrigerant is pumped through
the loop, heat is transferred directly through the copper
to the earth.
Never buy such a system!
I
do not recommend direct burial of refrigerant-filled copper
pipe due to the short lifespan of copper buried in contact
with acid rain or acidic soils.
I
believe such systems are installed only by irresponsible contractors
with a disregard for the customer's interests. Such systems
have a somewhat lower initial cost, and a higher heat transfer
capacity. Those advantages are more than offset by an environmental
issues regarding Freon leaks up from under the soil, which
could cause damage to the ionosphere, and the near impossibility
of locating or repairing such leaks should they occur.
The
Freon filled copper pipes required by this irresponsible design
contain vastly more Freon that is normally used in a heat
pump.up to 100 times more! The slightest leak then causes
massive damage to the ionosphere and repeated huge Freon Re-charge
bill to the homeowner to keep refilling a damaged and leaking
system, creating further ozone depletion.
NEVER
INSTALL one of these irresponsible Freon-in the ground type
geothermal systems. They are a stupid and foolish attempt
to cost cut the original installation costs by using a ridiculously
poor failure prone design. They serve only to give an otherwise
wonderful way to heat and cool a bad reputation due to a few
irresponsible contractors who promote them. In a properly
designed sytem only a few pounds of Freon are needed, and
that never leaved the indoor unit. Instead, a solution of
water and propylene-glycol (an environmentally friendly anti-freeze)
is all that circulates in the ground contact loop. And the
water-antifreeze mixture is safely contained in PWX (Cross
linked polyethylene) plastic tubing, not copper as Freon requires,
so there is no risk at all that the tubing will corrode in
contact with acidic soils or acid rain!
The
Freon remains safely sealed inside the heat pump compressor,
evaporator and condenser heat exchangers. There is simply
no opportunity for ant Freon filled copper to be exposed to
harsh and corrosive acidic soil conditions. As a result, the
modern heat pump has a very long life, and at the end of the
life cycle, the old heat pump's Freon is recovered and re-used
again and again to produce new heat pumps. Even with extensive
use of ground contact geothermal heat pumps, there is no need
to risk Freon loss, and No Freon need be lost to damage the
ionosphere at all!
The
length of the loop depends upon a number of factors, including
the type of loop configuration used; a home's heating and
air conditioning load; soil conditions; local climate; and
landscaping. Larger homes with larger space conditioning requirements
generally need larger loops than smaller homes. Homes in climates
where temperatures are extreme also generally require larger
loops. A heat loss/heat gain analysis should be conducted
before the loop is installed.

Types of Loops
Most
loops for residential geothermal ground contact heat exchange
systems are installed either horizontally or vertically in
the ground, or submersed in water in a pond or lake. In most
cases, the fluid runs through the loop in a closed system,
but open-loop systems may be used where local codes permit.
Each type of loop configuration has its own, unique advantages
and disadvantages, as explained below:

Horizontal
Ground Closed Loops.
This
configuration is usually the most cost effective when adequate
yard space is available and trenches are easy to dig. Workers
use trenchers or backhoes to dig the trenches three to six
feet below the ground, then lay a series of parallel plastic
pipes. They backfill the trench, taking care not to allow
sharp rocks or debris to damage the pipes. Fluid runs through
the pipe in a closed system. A typical horizontal loop will
be 400 to 600 feet long per ton of heating and cooling capacity.
The pipe may be curled into a slinky shape in order to fit
more of it into shorter trenches, but while this reduces the
amount of land space needed it may require more pipe. Horizontal
ground loops are easiest to install while a home is under
construction. However, new types of digging equipment that
allow horizontal boring are making it possible to retrofit
geothermal ground contact heat exchange systems into existing
homes with minimal disturbance to lawns. Horizontal boring
machines can even allow loops to be installed under existing
buildings or driveways.
Vertical
Ground Closed Loops.
This
type of loop configuration is ideal for homes where yard space
is insufficient to permit horizontal buildings with large
heating and cooling loads, when the Earth is rocky close to
the surface, or for retrofit applications where minimum disruption
of the landscaping is desired. Contractors bore vertical holes
in the ground 150 to 450 feet deep.

Each
hole contains a single loop of pipe with a U-bend at the bottom.
After the pipe is inserted, the hole is backfilled or grouted.
Each vertical pipe is then connected to a horizontal pipe,
which is also concealed underground. The horizontal pipe then
carries fluid in a closed system to and from the geothermal
ground contact heat exchange system. Vertical loops are generally
more expensive to install, but require less piping than horizontal
loops because the Earth's temperature deeper down less affected
by surface temperature and is thus cooler in summer and warmer
in winter.
Remember
the U tube experiment in your elementary science class. In
a clear glass U-tube (closed at the bottom) when you pour
water into one leg, the water "would seek its own level" in
the other leg of the tube,. Since the weight or the water
in one leg pushes downward, the water in the other leg raises
until the weight of both columns of water is equal. Thus water
seeks its own level.
What
does this mean to you as a homeowner?
What
it means is that even with a deep well U-tube, in a closed
loop system, water will seek its own level without you having
to pay for ant expensive pump energy to make it do so!
So
even if your ground contact heat pump well is hundreds of
feet deep, simply allowing water to enter one leg will cause
water to exit the other leg without ant need whatsoever to
expend any energy to pump the water up from even the deepest
well.
That
is a major advantage of a closed loop system. It is such an
advantage that an open loop system should not even warrant
further consideration. Even if you have a pond or other warm
water source, you are better off just adding a closed loop
under it to avoid pumping costs.
Pond
Closed Loops. If a home is near a body of
surface water, such as a pond or lake, this type of loop design
may be the most economical. The fluid circulates through polyethylene
piping in a closed system, just as it does in the ground loops.
Typically, workers run the pipe to the water, then submerge
long sections under water. The pipe may be coiled in a slinky
shape to fit more of it into a given amount of space. Geothermal
ground contact heat exchange experts recommend using a pond
loop only if the water level never drops below six to eight
feet at its lowest level to assure sufficient heat-transfer
capability. Pond loops used in a closed system result in no
adverse impacts on the aquatic system.
Open
Loop System. This type of loop configuration
is used less frequently, due to the irresponsibility of permanently
draining an aquifer just to obtain heating or cooling! It
may be employed cost-effectively if ground water is plentiful.
Open loop systems, in fact, are the simplest to install and
have been used successfully for decades in areas where local
codes permit. In this type of system, ground water from an
aquifer is piped directly from the well to the building, where
it transfers its heat to a heat pump. In a somewhat more environmentally
acceptable open-loop scheme, the water is returned to the
Aquifer via an injection well.
After
it leaves the building, the water is pumped back into the
same aquifer via a second well--called a discharge well--located
at a suitable distance from the first. Local environmental
officials should be consulted whenever an open loop system
is being considered.
Often,
such new installations are prohibited by law. Even where permitted,
the operating costs can be higher due to costly energy consumed
by deep well source and re-injection pumps.
Standing
Column Well System. Standing column wells,
also called turbulent wells or Energy Wells, have become an
established technology in some regions, especially the northeastern
United States. Standing wells are typically six inches in
diameter and may be as deep as 1500 feet. Temperate water
from the bottom of the well is withdrawn, circulated through
the heat pump's heat exchanger, and returned to the top of
the water column in the same well. Usually, the well also
serves to provide potable water. However, ground water must
be plentiful for a standing well system to operate effectively.
If the standing well is installed where the water table is
too deep, pumping would be prohibitively costly. Under normal
circumstances, the water diverted for building (potable) use
is replaced by constant-temperature ground water, which makes
the system act like a true open-loop system. If the well-water
temperature climbs too high or drops too low, water can be
"bled" from the system to allow ground water to
restore the well-water temperature to the normal operating
range. Permitting conditions for discharging the bleed water
vary from locality to locality, but are eased by the fact
that the quantities are small and the water is never treated
with chemicals.
Other
loop designs are also being used. In a few places, for example,
home builders have installed large community loops, which
are shared by all of the homes in a housing development.
An
even more enlightened approach
Although
a closed U-Tube well needs no deep well pump, you will still
need a very small circulation pump to circulate the water
through the heat pumps sink/source heat exchanger. The energy
needed to do this is trivial however, since water has a heat
capacity 3500 times that of an equivalent volume of air. So
only a few gallons per minute of water circulation is needed
even in a very large installation, because water can carry
so much heat.
If
you choose zone Hydronics (radiators or chillers with fans)
instead of air handlers, the need for air ducts is eliminated,
and the energy needed to distribute the heating or cooling
is slashed dramatically.
Then
just a small 12 volt DC pump can circulate the tempered water
and small quiet 12 volt muffin fans can provide the zone heat
transfer. The tiny pumps and blowers can then be powered by
a 12 volt deep-cycle auto battery recharged from a small solar
panel. Such a system can maintain a 60 ° F baseline home
temperature right through hurricanes and ice storms, since
the electric power grid is not even required to maintain that
temperature since the heat pump is not even needed to get
60 ° F. That comes free from the ground contact loop.
In
fact it is even possible to eliminate the heat pump all together,
and just use some simple alternative heat sources in winter,
such as vacuum tube/ heat-pipe solar collectors connected
to a hot water storage tank.
 
Innovative,
evacuated (vacuum) tube collectors, combined with heat pipes
to act as thermal check- valves, to remove the collected heat,
and swiftly transport the heat to a safe storage area, (before
the heat re-radiation occurs) allow high temperature solar
thermal collectors to produce high temperature water even
on the coldest sunny winter days!
Such
a system needs no fossil fuel or grid
power whatsoever and adds an extra 10-15 ° F
from previously captured solar heat to Virginia's free 60
° F free-for the taking ground contact thermal resource.
The
result is year-round heating and cooling comfort, with no
need for fossil fuel consumption, and with no electric bill
to run a heat pump either!


Almost
everything you have ever heard about geothermal energy refers
to HIGH TEMPERATURE Geothermal Systems. These can not be used
everywhere, and are highly dependent on location.
Do
not confuse high temperature geothermal sites which are scarce,
with the low temperature geothermal that can heat and cool
your home .
High
temperature sites are undesirable for home cooling because
they are too hot!
The
low temperature geothermal resource is almost everywhere!
It
is ubiquitous free-for-the-taking free energy!

There
are only a few really good high temperature geothermal sites
located on the continents of Earth . most are under the oceans!

The
much deeper ground temperature (about two miles down) is much,
much hotter than at the surface, as shown in the map below,
So geothermal Heat Pumps tap into the deep core heat of Planet
Earth heat much more than the Solar ground heat!

The
geothermal heat pump does not require a special hard to find
high temperature geothermal location, and uses only the just
under the surface, low temperature ground heat resource, and
therefore this free energy resource is available throughout
the USA.

The Central Virginia Area has an ideal
57-60º F (15.5ºC) deep ground temperature!

Abundant Energy at a perfect temperature!
It is Free-For-The-Taking . Forevermore.

Notice that Hopewell Virginia has a
1 ° F higher temperature free energy thermal extraction
resource than does Goochland Virginia!
Central Virginia is very lucky to have
such an ideal 60 ° F (16 ° C) Free Energy Ground Temperature
Resource!

Even
on a very local scale the tiny variation in the deep ground
temperature free energy resource are predictable. Here the
State capitol is shown in yellow,
as are TJ High School, the DMV Headquarters, and the VA Museum
of Fine Arts. Note that the free energy geothermal resource
at the state capitol is 0.15 ° F warmer that that at TJ
High School, and 0.08 ° F warmer than at the DMV and 0.1
° F warmer than at the Arts Museum! These very predictable
resource temperatures allow fore very careful system designs
optimized to your exact location!
An even more enlightened approach
Although
a closed U-Tube well needs no deep well pump, you will still
need a very small circulation pump to circulate the water
through the heat pumps sink/source heat exchanger. The energy
needed to do this is trivial however, since water has a heat
capacity 3500 times that of an equivalent volume of air. So
only a few gallons per minute of water circulation is needed
even in a very large installation, because water can carry
so much heat.

In
Virginia, extremely careful design combined with Virginia's
abundant sunshine and free 60 ° F geothermal ground temperature
resource, can result in a real energy independent home. Such
a home works right through ice storms and hurricanes ,
maintaining comfort because it is free of fossil fuels, and
requires no electrical grid connection for continued operation
of its free-energy heating and cooling system!
If
you choose zone controlled Hydronics (radiators or chillers
with fans in each room) instead of ducted air handlers, the
need for air ducts is eliminated, and the energy needed to
distribute the heating or cooling is slashed dramatically.
Then
just a small 12 volt DC pump can circulate the tempered water
and small quiet 12 volt muffin fans can provide the zone heat
transfer. The tiny pumps and blowers can then be powered by
a 12 volt deep-cycle auto battery recharged from a small solar
panel. Such a system can maintain a 60 ° F baseline home
temperature right through hurricanes and ice storms, since
the electric power grid is not even required to maintain that
temperature since the heat pump is not even needed to get
60 ° F. That comes free from the ground contact loop.
In
fact it is even possible to eliminate the heat pump all together,
and just use some simple alternative heat sources in winter,
such as vacuum tube/ heat-pipe solar collectors connected
to a hot water storage tank.
Innovative,
evacuated (vacuum) tube collectors, combined with heat pipes
to act as thermal check- valves, to remove the collected heat,
and swiftly transport the heat to a safe storage area, (before
the heat re-radiation occurs) allow high temperature solar
thermal collectors to produce high temperature water even
on the coldest sunny winter days!
Such
a system needs no fossil fuel or grid
power whatsoever and adds an extra 10-15 ° F
from previously captured solar heat to Virginia's free 60
° F free-for the taking ground contact thermal resource.
The
result is year-round, inexpensive, hassle-free heating and
cooling comfort, immune to power outages, with no need for
fossil fuel consumption, and with no electric bill to run
a heat pump either
This technology works great and saves
$$$ in fossil fuel costs.
Feel
free to E-mail me if you have any questions.
With
Best Regards,
Patrick
Ward
FREE
ENERGY
fossilfreedom@yahoo.com
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