Taking the chill off with a solar pool cover for your pool

December 27, 2023

When the air gets cooler but you’re not ready to say goodbye to pool days, a solar pool cover is your best mate. It’s not just a smart way to extend your swimming season. Let’s dive into what makes these covers a brilliant choice for your pool.

What is a Solar Pool Cover?

Imagine a pool cover that not only keeps out unwanted bits like leaves but also works like a mini greenhouse for your pool. That’s your solar pool cover. Unlike regular covers, these are specifically designed to absorb sunlight and trap the heat, keeping your pool warm and inviting.

Solar Cover Types

Solar Blankets

Picture a big bubble wrap laid out over your pool. Easy to roll out and pull back, these blankets are perfect for everyday use. They trap heat efficiently but can be a bit of a wrestle to handle when it’s time to swim. Bear in mind it’s much more durable than bubble wrap and won’t stand up to the conditions as one user pointed out here back in 2007. You can buy them in most places like Clark Rubber or local retailers.

Image courtesy of Clark Rubber


Solar Discs

These are nifty little circles that float on your pool’s surface. Ideal for any pool shape, they’re super easy to pop in and out. While they cover less surface area than blankets, they’re great if you’re after something quick and simple. Here you can see some solar discs/rings on Amazon (hard to find on the AU version) but videos like this one attempt to teach you how to make your own solar pool rings from some tubing, zip ties and a cheap Amazon solar blanket which then begs the question – why not just use the solar blanket?

Liquid Solar Covers

This is the latest in pool cover tech. You pour a liquid into your pool that creates an invisible layer on the water’s surface. It’s fuss-free but doesn’t match up to the traditional covers in terms of heat retention.

In short, this liquid solution works by covering the top of the water with a thin layer fatty alcohol that is one molecule thick. You can’t see, smell or taste it (but please don’t try). That fatty layer of alcohol covers the surface of the water the same way a blanket might and prevents evaporation and therefore cooling.

If you want to pick some of this up, Direct Pool Supplies AU has you covered.

Solar Pool Cover Materials

  • Vinyl: Thick and durable, vinyl covers are like the sturdy boots of pool covers – they last. They keep the heat well but might be a bit heavy on the pocket and to move around.
  • Polyethylene: Lighter and easier on the wallet, polyethylene covers are like the sneakers of pool covers – practical for the regular user. They might not last as long as vinyl but are a good bang for your buck.
  • Polypropylene: If solar covers had a luxury option, this would be it. Strong and effective at blocking UV rays, these covers are a long-term investment. They do cost a bit more, but you’re paying for quality.

Benefits of Solar Pool Covers

Every pool loses heat during the day. Evaporation accounts for 75% of that heat loss. To greatly reduce this loss, a barrier is needed between the water and air. Using a solar pool cover could save as much as 70% on the heating costs you are now paying to keep your pool heated. You could also benefit because you will need to replace less water since you will not be losing as much from evaporation.

Not only will the solar cover keep the water from losing heat so your heater doesn’t have to work as hard but it could help distribute the heat more evenly so there are fewer cold spots. Your morning swim may be more pleasant as well when the cover is kept on overnight. Less heat will be lost during the night so the water will not be as chilly as it normally would be in the morning before the sun and heating system have had a chance to bring it back up

Using a solar pool cover is like putting a lid on your coffee cup – it keeps the heat in.

solar heat retention in a pool

How to Choose the Right Solar Pool Cover

Picking the right cover isn’t just about the size and shape of your pool. Think about how often you’ll use it, your local weather patterns, and how much you’re willing to spend. It’s about finding that sweet spot between functionality and budget.

1. Measure your pool
The size of a cover regardless of type, will depend on the size of your pool. As most covers (liquid and blanket) cover the entire surface area of the pool this is important. Even for those covers that don’t like solar discs you want to know exactly how many you’d need to buy so make sure you measure twice and order once!

2. Choose a solar cover type
If you’re not sure what to choose we’ve covered them off above. Each solar cover has its advantages and disadvantages.

3. Select a colour and thickness
If you’ve decided to go with something like liquid pool covers or even the solar discs this step is not needed but, if you are thinking a solar blanket is the best option you’ll have to decide on a thickness and colour.

Solar Cover Thickness – Measured in mils the thickness of pool covers comes in three levels 8 mil (thin), 12 mil (medium) and 16 mil (thick). The thickness of the solar cover increases the amount of heat that it can retain but it also increases the weight, cost and lifespan of the cover. So, while a lighter cover might be cheaper it will also be less effective and not last as many years as a thicker cover.

ThicknessWeightTemp SavedPriceDurability
8 milLightestLow$Low
12 milModerateMid$$Mid
16 milHeaviestHigh$$$High
Pool Cover Thickness to Benefit Table

Solar Cover Colour

The colour is generally a personal choice, darker colours block more sunlight which can be better at reducing algae however the colour of your cover mostly adds ambience to your backyard, especially at night with the pool lights on. There are many colours to choice from depending on the manufacturer or retailer including clear, blue, red and purple.

Installation and Maintenance

Getting your solar cover on your pool is a bit like making your bed. It needs to fit right and lay flat. Regular cleaning and proper storage will keep it in good nick for longer. Remember, a well-maintained cover is a long-lasting cover.

When Using Your Pool

Remove the cover first before you use the pool and enter the water. Never try to swim with or underneath the cover when it is in the pool.

Keep the cover rolled up neat and evenly and out of direct sunlight. If you have a roller they will generally come with a top cover to go over your pool cover and protect it from direct heat. If you do not have a roller or your cover be sure to store you pool solar pool cover out of direct sunlight when its not in contact with the water as it can damage the material.

When Using Your Cover

  1. Do not swim in the pool or let anyone attempt to walk, run or jump onto the cover. Solar covers are not safety covers and it can be extremely dangerous for people and pets if they were to fall into the water with the cover. Remove the cover before any pool activity (including cleaning your pool).
  2. When setting up your cover do not drag and pull the cover over paving or timber decking or other hard surfaces. If you do not have a cover roller to help you unfold your cover you should ask another person to help you so that you don’t accidentally let it catch on something and damage it. Any damage can reduce the effectiveness of the cover considerably.
  3. When the cover is unfolded remember to protect it by keeping it out of direct sunlight on days where temperatures exceed 38 degrees celsius. Hot days can damage the cover and lead to excesses of chlorine gasses underneath your cover.
  4. Pool covers are made for standing up to pool chemicals when kept at a normal level but excessive chlorine and chemicals can damage it. So, be sure to keep the pool cover off after shocking your pool (super chlorination) anything higher than 2.5 ppm chlorine level will damage the cover be sure to keep your pool cover off the pool until the chlorine levels have returned to the 1ppm to 2.5ppm range.

When Using Your Cover For Long Periods (like if you’re travelling or not in the pool)

Be sure to;

  • Keep the filtration system running during the hottest time of the day, usually between 11.00 am and 3.00 pm.
  • Occasionally remove the pool cover when the pool is not being used for a long time to release the build-up of chlorine gas.
  • Remove the pool cover completely when going away. The build-up of concentrated chlorine gas between the pool water surface and the cover will damage it over a long time.
  • Ensure the cover is clean and try if you are going to store away the cover for a long period

How to Care For Your Pool Cover

  1. Hose off dirt and debris such as leaves towards the skimmer box while the pool pump and filtering system is running.
  2. Never walk, jump or run on the cover
  3. Roll or fold it up neatly when not in use and stored in the shade or, with a white reflective cover over the top of the roller.
  4. Unfold and store the cover with the help of a roller or another person to make sure it doesn’t get damaged on hard surfaces or caught on pavers, a deck or other poolside obstacles.
  5. Keep the pool cover out of temperatures above 38 degrees Celsius.
  6. Only use the cover when chlorine levels are within a normal range.

FAQs

  • How does a solar cover work?
    It traps the sun’s heat and uses it to warm your pool.
  • How should a solar pool cover fit?
    It should cover the entire surface of your pool without hanging over the edges in the case of a solar blanket. Solar discs however should be expected to “fit” by covering approx 80% of the pool surface.
  • Can you run a pool pump with a solar cover on?
    Sure can. It doesn’t affect the pump’s operation.
  • What is a good thickness for a solar pool cover?
    Around 12-16 mils is ideal for a balance of insulation and manageability.
  • Do solar covers increase algae?
    Not if you maintain your pool and cover it properly.
    Because algae likes warmer waters and exposure to sunlight some darker covers can reduce algae although many people have said that it appears they have a larger growth of algae after getting a pool cover.