Posted: May 30, 2023
Categories: Heating, Pool Maintenance, Swimming Pool Products
Author: Phillipa White
How Effective are Solar Pool Covers?
Swimming pool covers can be invaluable when it comes to maintaining the health of your pool – and solar covers are lauded as doing more than just keep debris out of your water! But how effective are they really?
We consider whether solar and GeoBubble pool covers are worth using during the spring and summer months.
What Do Solar Covers Do?
Like other coverings that shield your pool’s water, solar covers help stop debris from entering the pool and reduce chemical loss. Crucially, they will also help prevent evaporation, which has a cooling effect. GeoBubble, a leading brand for solar pool covers, states that when you cover a pool, you can prevent 98% of evaporation, ensuring far less heat is lost this way.
Due to being made from translucent or transparent materials, solar covers also let the sun’s heat through, transmitting it into the water. With these properties that allow for solar gains and heat retention, using a solar cover during the swimming season should help you save money on heating as your heaters don’t have to work as hard, and you can rely on them less.
Do Solar Pool Covers Work?
The biggest question is, how effective are these properties in practice? Solar covers are made of a bubble wrap-like material, which traps air and acts as an insulation layer. This then helps keep your water at the desired temperature.
But the efficacy of this bubble technology will depend on a couple of things.
Weather & Temperature
This is fairly obvious, but you’ll see more solar gains if you live somewhere that is consistently sunny. However, this is not to say that you won’t see any benefits if you’re using the cover somewhere a little cloudier (i.e. across the UK)!
Similarly, if the air temperature is colder, your solar cover will take longer to have a sufficient warming effect on the water – they are more useful in spring and summer.
Pool Size
If you have a big, deep pool, you will also have to wait longer for solar covers to have a warming effect. Deeper water is also less likely to retain heat for as long, so solar gains and heat retention may seem less significant than for smaller pools. Again, this does not mean solar pool covers won’t work for bigger pools, as they will still prevent mass heat loss from evaporation and support heat retention overnight.
Solar Cover Thickness
Generally, the thicker the cover, the better it will be at retaining heat. Good-quality covers will usually vary from 400-600 microns.
Solar Cover Colour
The colour of your solar cover can also play a big role in how effective it is at allowing the sun’s energy to heat up the water. If your cover is more transparent, it will be able to transmit more heat to your pool water. Alternatively, dark opaque covers will absorb more heat but are less effective at passing that heat onto the rest of the water, warming only the surface area.
How Many Degrees Will a Solar Cover Heat a Pool?
If the conditions are right, a solar cover could help increase the temperature of your pool water by up to 8°C (also depending on the type of cover you get). This can greatly reduce the demand on your heating system, saving energy and money. You can expect these kinds of results with something like the Sol+Guard 500M GeoBubble Solar Cover.
If you don’t live in the sunniest of places and want to keep your pool at a consistent temperature, you’ll likely want to use your solar cover in tandem with some form of heating system, such as a solar pool heater. As another wonderfully energy-efficient option, swimming pool heat pumps are ideal here, helping to heat your pool with minimal electrical input and a very low operational cost.
How Quickly Will a Solar Cover Heat a Pool?
Again, this will largely depend on how much direct sunlight your cover receives and the other factors previously discussed. Most sources seem to agree that it can take two or three days of consecutive sunny weather to see the expected rise in temperature.
It’s important that you cover your pool as soon as it’s no longer in use as evaporation and heat loss can occur rapidly, so it’s best to keep all that heat trapped in with the cover, especially overnight.
Do Solar Pool Covers Work on Cloudy Days?
When the weather is overcast and your cover is subject to less direct sunlight, you can obviously expect fewer solar gains. However, this is not to say that your solar cover will be redundant on cloudy days, as you may still see some small increases in temperature when using it.
This is why it’s important to use your cover along with another heat source, as you’ll be able to more effectively maintain a consistent temperature. Additionally, the other benefits inherent to solar covers (debris prevention, heat retention, evaporation reduction) will remain true, no matter the weather.
Do Solar Pool Covers Cause Algae?
One thing that people are cautious about when it comes to solar pool covers is whether they’ll promote algae growth. Algae loves warm water and exposure to sunlight, so if you’re not using the right chemicals, you may get a bit of algae growth when using a more transparent solar cover.
If you’re worried about continued algae growth, you can get specialist covers that inhibit its growth by absorbing the light responsible for photosynthesis. The Energy Guard 500M GeoBubble Solar Cover is a great example of this kind of covering.
Are Solar Pool Covers Worth It?
In our opinion, yes, solar pool covers are worth it. There aren’t really any downsides to using one, and you’ll get a whole host of benefits that’ll keep your pool ticking over for the duration of the season!
GeoBubble technology is designed to be more durable than previous designs, lasting up to 25% longer due to the improved bubble structure. This makes these solar covers a fantastic investment, serving you well for years to come.
We wouldn’t recommend using a solar cover all year round, as a hardier winter debris pool cover will be able to hold up more successfully during winter.
If you want to experience the benefits of solar covers first-hand, remember to check out our range of GeoBubble covers! Getting ready to open your pool again this year? Head over to our step-by-step guide on opening your pool for spring, so you've got everything you need to get started.
