There are a few ways pool and spa owners can save money on energy of which
two are turning the circulation pump off when the pool or spa isn’t
being used (or at least lowering the speed) and lowering the
temperature of the water when the pool or spa isn’t being used.
Lowering the temperature during the keep out hours can easily save as much as
$200 per month or more. To do this you need a temperature controller
that is set up for the days of the week type of control with the
ability to set the time to lower the temperature at night and the
time to set it back in the morning. It will need to be set back at
least an hour before the opening hour to make sure the temperature is
back to normal. A side benefit of lowering the temperature at night
is that will reduce usage of the pool or spa during during those
hours. Imagine sneaking into a spa late at night long after it is
closed only to find the water is 90°F instead of 104°F.
Most commercial pools and spas keep the circulation pump running 24 hours
per day. Most of these pumps are over sized and turn over the water
more than needed but that is the way it is. A variable speed pump can
save a lot of money as you can lower the speed to get the desired
turnover rate which could be every 6 hours. A better approach is to
let the pump run at full speed when the pool or spa is open, and then
lower the speed when it is closed. To do this right would require the
ability to be able to set the open and closed times for each day of
the week.
There are controllers for heaters and even some heaters have it built in
the ability to have two temperature setpoints to realize the savings
in lowering the temperature during the pool or spa closed hours. The
same also goes for the variable speed pumps.
The PoolWarden is a water chemistry controller, meaning that it measures
pH and ORP and controls relays that can feed corrective chemicals to
keep the water chemistry in balance. The PoolWarden also has energy
management built in allowing for control of up to three of any
combination of heaters and variable speed pumps. There are two time
profiles (supporting if you have a pool and spa with different
operating hours) that include a morning time and evening time for
each day of the week. When the time is between these two times the
heater or pump will be running normal, when not between these two
times the heater will be at a lower temperature and the pump will be
at a lower speed.
A PoolWarden that controls two pools including sensors and flow cells
goes for about $2000. If you save $200 per month lowering the
temperature of the heaters at night that would pay for adding water
chemistry control in a short 10 months, not even counting what can be
saved by using the right amount of chlorine and acid/base. The
PoolWarden also tracks relay on time, you can actually see the hours
that the equipment is in the lower energy usage mode and easily
calculate the savings.
By Scott Lenney
ControlOMatic
Great blog. I thought your points were great about how to save money on energy, and the entire site is informative for future customers. Thanks for writing!
Since the pool will not be directly coceentnd to the home it will help control humidity in your house. My neighbors many years ago had an outdoor/indoor swimming pool. Something you might consider. The pool area was surrounded by 3 walls of glass windows. The wall structure was built with strong aluminum (I think it was aluminum, something that will not rust, etc.) supporting frames and insulated glass panels. Cute decals on the glass panels were applied to show the glass was there. Every 6 feet or so on two glass walls were sliding glass doors. These could be opened in the warmer months during the day. This will refresh the air inside and cut down on humidity and the chlorine smell. Interior potted plants love the sunshine and fresh air. The other remaining wall was built with inexpensive concrete blocks painted with marine paint. This wall was for decoration and placing racks or shelves for swimming gear, etc.The ceiling of the pool area was strong fiberglass panels. The kind that are shaped in an S’ pattern when looking at it from the side. I can’t remember what this pattern is called.The deck around the pool area was concrete that was prepared before the walls were put up. By the way this was an underground pool.During the winter it was fun and strange to see the snow outside through the windows and still be enjoying a heated pool.
I would strongly asdvie against it. Natatoriums as they are called in the biz are one of the more challenging design problems I have been involved with. I design HVAC systems. I have concluded that an pool is simply the worst thing you could ever put inside a building. As has already been stated, it only works if you are willing to spend a ridiculous amount of money. The short answer is that indoor pools must be maintained at an exact temperature as well as the air. The relationship between the air and water temps has to do with minimizing the evaporation rate of the pool. You simply can’t allow excessive moisture in the air. Even still, you must provide a rediculous amount of venilation in the space to remove moisture and chlorine gas. Even the ductwork to provide the ventilation is more expensive because cheaper materials will corrode due to the chlorine. Honestly, you won’t get the fine control you need out of a wood stove either unless it’s a wood pellet boiler.Just don’t do it. It will be a headache for you for sure.