Pool covers are highly recommended in all indoor pools rooms where
it is feasible to use one. This includes residential projects, rehab/therapy
projects where water temperatures are higher than normal, and some commercial
projects. Vary rarely will we find a school/college, hotel, YMCA, etc.
using a pool cover and this is normal.
Pool covers reduce the evaporation rate of the water; hence dehumidification
does not have to run 24 hours/day reducing the overall operating
costs of operation. They also reduce costs of heating the pool,
and reduce chemical loss due to evaporation.
Overall, pool covers can save 50-75% of operating costs within a poolroom.
The following information is from RSPEC on Indoor Pools.
There are many types of covers from hand rolled to automatic with the
push of a button. The automatic covers are more expensive, but
you will find they are being used for a number of reasons:
Elderly people generally can’t roll up covers.
-Some covers prevent small children and people from falling through them
into the pool, so they are also a safety barrier.
-The convenience of pushing a button to open and close the pool.
-Reduces evaporation rate of pool water, and reduces costs of operation
OVERVIEW from
R-SPEC
Indoor swimming pools are big energy consumers. Pool owner/operators spend billions
of dollars annually to heat the nation's pools. Much of this energy is often
wasted and can be saved with proper management. Wasting energy also contributes
to our growing air quality problem. RSPEC! is a national program that asks you
to consider measures to Reduce Swimming Pool Energy Costs.
HOW
POOLS LOSE HEAT
Pools lose energy in a variety of ways, but evaporation is by far the largest
source of energy loss for swimming pools. When compared to evaporation, all other
losses are small.
The reason evaporation has such an impact is that evaporating water requires
tremendous amounts of energy. It only takes 1 Btu to raise 1 pound of water 1
degree, but each pound of 80 water that evaporates takes a whopping 1048 Btu's
of heat out of the pool. WHY POOL COVERS
Since evaporation is the major source of heat loss for all swimming pools, to
minimize evaporation one must cover the pool. Covering the pool with a pool cover
when it is not in use is the single most effective means of reducing pool heating
costs. Savings of 50-70% are possible. INDOOR POOLS
The next diagram illustrates the impact of evaporation on the total energy consumption
of the indoor pool.
When we compare outdoor and indoor energy loss characteristics, energy loss vehicles
may change, but the percentage for evaporation remains high.
Indoor pools are not subject to the fluctuations in day and night temperatures
of outdoor pools. Neither do they radiate heat to the night sky, nor have winds
that carry the heat away from the pool; but they do require room ventilation
to control indoor humidity caused by the large amount of evaporation. Without
a proper ventilation system, high indoor humidity levels will cause numerous
problems, including condensation on cold surfaces and rusting of structural components.
The energy required to run a ventilation system adds to the costs of operating
an indoor pool. Also, the ventilated air must be conditioned, which adds further
to the costs.
TYPES
OF POOL COVERS
Technically, all you really need is a large sheet of plastic. Plastic
meets the requirement of being a vapor barrier. But a large sheet of
plastic that you get from the lumber store is probably not your best
choice. It will be very difficult to handle and store, it tears easily,
and sunlight will deteriorate it rapidly. You can use it, but it will
be very inconvenient and will only last 1 to 2 seasons max.
There are a number of manufacturers that produce covers designed specifically
for swimming pools. They can be made of different materials, such as
UV stabilized polyethylene, polypropylene, or vinyl. They can be transparent
or opaque. They can be light colored or dark colored
One of the
lowest cost covers made specifically
for swimming pools is the bubble
cover (some call them solar covers).
They
are similar to bubble packing material
except that they use a thicker grade
of plastic and have UV inhibitors,
etc.
Vinyl covers are a heavier material and have a longer life expectancy. You can
also get insulated vinyl covers with a thin layer of flexible insulation sandwiched
between two layers of vinyl.
Outdoor pools gain heat from the sun, absorbing 75-85% of the solar energy striking
the pool surface. This is an important contribution to the pool heating needs.
So when considering a pool cover, note that a pool cover will also decrease the
solar gain contribution to the pool to some extent, depending on the type of
pool cover used. A transparent bubble cover may reduce pool solar energy absorption
by 5-15%, and a completely opaque cover by 20-40%.
METHODS OF
USE
There are several ways of covering your pool. The simplest and lowest first cost
method is to manually pull the cover on and off, fold it, and place it somewhere
out of the way. If you are paying someone to do this, you need to consider that
cost in your economic evaluation. You can also purchase a pool cover reel that
can be used to manually roll the pool cover up. The reel, usually on wheels,
can then be rolled out of the way.
Semi-automatic covers use a motor driven reel system. They use electrical power
to roll and unroll the cover, but usually require someone to pull on the cover
when unrolling, or guide the cover onto the reel when rolling the cover up. They
can be built into the pool deck surrounding the pool, or can use reels on carts.
Automatic covers have permanently mounted reels that automatically cover and
uncover the pool at the push of a button. They are also the most expensive first
cost option. But you have to weigh the cost of labor for the manual and semi-automatic
covers to determine which route is best for your particular situation.
Some pool covers are fitted into tracks along the sides of the pool. This prevents
anything or anybody from getting into the pool. They even support the weight
of several people. If liability is a concern, these are a good option to explore.
They can be run manually, semi-automatically, or automatically.
OTHER BENEFITS
Pool covers also provide many other benefits beside the tremendous energy savings.
They conserve water by reducing the amount of make-up water needed by 30-50%.
They can reduce chemical consumption by 35-60%. They also cut cleaning time
by keeping dirt and other debris out of the pool.
It is highly recommended that the first step to cutting pool energy loss be the
evaluation of the economics of using a swimming pool cover.
(To clarify, we are not talking about pool covers that you use to cover the pool
in the off-season or mesh safety covers. Those do not save energy. We are talking
about plastic or vinyl pool covers that you use during the swimming season when
the pool is not in use.)
EPS is the home of DRY-AIR & VERI-DRY. We provide Design, Engineering, Consulting and Manufacturing for Residential and Commercial Indoor Swimming Pool Applications.
