To cut the energy bill on a pool, start with the three places the energy actually goes: heat lost from the water surface, the circulation pumps, and (indoors) heating and ventilating the hall. A cover, a sensible temperature set-point and pumps that are not running flat out all day will do more than any change to the water treatment. NanoSWIM sells water treatment, so we say this plainly: treatment is not primarily an energy product.
Where Does a Pool's Energy Actually Go?
Water holds heat well and gives it up fast to the air above it. Every warm surface that evaporates takes energy with it, and an indoor hall then has to heat and dry the extra moist air. Add the pumps that move the whole water volume through the filters, and you have the three big lines. Lighting, controls and pool-side equipment come after.
That order matters, because it tells you where effort pays. The table below ranks the usual measures by how likely they are to move the bill.
| Measure | Which line it hits | Fits which pools | Catch |
|---|---|---|---|
| Pool cover when closed | Water heating, evaporation | Indoor and outdoor | Only works if staff actually use it every night |
| Lower water temperature set-point | Water heating, hall heating | All | Swimmers and instructors notice; agree the level with users first |
| Heat recovery on ventilation air | Hall heating | Indoor | Needs space and capital; best done at a refurbishment |
| Heat pump for water heating | Water heating | All | Efficiency depends on the heat source and the temperature it must reach |
| Variable-speed pumps and sensible run hours | Circulation | All | Flow still has to meet the hygiene design; do not simply turn it down |
| Clean filters and correct backwash control | Circulation, make-up water | All | Dull, but a clogged filter makes the pump work harder |
| Change of water treatment method | Chemicals, indirectly ventilation | Depends on the site | Not a heating measure |
How Much Can a Pool Cover Save?
More than most operators expect, and it costs the least. At night, with nobody swimming, the open surface is simply evaporating warm water into the room. A cover stops that. In an indoor hall it also lowers the humidity the ventilation has to deal with, so you save on water heat and air heat together.
The limit is discipline. A cover that takes a whole crew and half the closing routine to roll out gets left in the store. If you buy one, check who closes the pool at the end of the day and whether that person can do it alone.
Should You Turn the Water Temperature Down?
Often yes, by a little, and it is free. The set-point in many pools is where it is because nobody has questioned it for years. But the pool is also used by children, the elderly and people in rehabilitation, and they need warmer water than lane swimmers. Do not set a number from a spreadsheet. Ask the instructors, then change it in small steps and watch the complaints.
Are Your Circulation Pumps Running Harder Than They Need To?
This is the line that gets overlooked. Pumps were often sized for a bather load that no longer matches the building, or throttled with a valve so the motor still draws full power while the flow is cut. Variable-speed drives, correct impeller sizing and run hours matched to actual use all reduce the load.
The honest limit: circulation exists for hygiene. In a public pool the turnover has to meet the design the facility was approved for under forskrift om badeanlegg, bassengbad og badstu, and the municipal health authority can ask about it. Turning the pumps down is a change to be made on paper first, with the operator and the supplier, not at the plant-room panel on a quiet afternoon.
Where Does Water Treatment Fit in an Energy Plan?
Modestly. NanoSWIM's technology is installed inline in the existing circulation loop, after filtration, so it does not heat or cool anything, and it does not replace the measures above. NanoSWIM publishes an energy saving of up to 40% in a general technology context. It is not a promise for any single installation, and it is not a reason to buy treatment instead of a cover or a pump upgrade. See how the technology works for the mechanism.
Where it can help indirectly is the air. Free chlorine reacts with what bathers bring into the water and forms chloramines, which end up in the hall air. The ventilation then runs harder to keep the air acceptable. A treatment that reduces chlorine use may reduce that load; whether it does, and by how much, depends on your pool and your ventilation. NanoSWIM's published chemical figure is up to 90% less chemical use against a conventional chlorine dosing regime on comparable pools. For a documented case, see the resort pool study, where the 60% lower cost applies to the water-treatment line only, not to total operating cost. The client is not named, for commercial confidentiality.
It is also a treatment-loop technology with no persistent residual in the basin on its own, and a Norwegian public pool must generally keep a measurable disinfectant residual, so the realistic result there is strongly reduced chlorine, not zero. Capital cost is higher than dosing pumps and drums. It does not replace correct filtration, sensible pH control or competent operation. If you also want to see where the money goes outside the energy lines, our articles on pool running costs go through the rest.
What Should You Check Before Spending Anything?
- Is the pool covered whenever it is closed, and can one person do it?
- When was the water temperature set-point last discussed with the instructors?
- Do the pumps run at a speed that matches the current bather load, or at full speed by habit?
- Is any pump throttled with a valve instead of slowed with a drive?
- When were the filters last checked, and is backwash controlled by pressure or by a clock?
- For indoor pools, is the ventilation tuned to the real humidity and air quality in the hall?
- Only then: is there a chemical or chloramine problem that justifies looking at the treatment method?
In my own experience, the hardest part of any upgrade is not the technology, it is flow rate and the space in the plant room. So the first thing I do in a plant room is put my hand on a pump motor and listen to it. You learn a surprising amount from a motor that sounds like it is working against a half-closed valve, and from the faces of the people who thought it was normal. Nobody likes hearing that the cheapest saving was the pump all along, but I would rather tell them that than sell them a bigger box.
If you want to know whether water treatment makes sense at your site, contact NanoSWIM in Bergen with your pool volume and circulation flow rate. We will tell you honestly if it fits, and if the better answer is a cover and a pump, we will say that too.