The use of solar energy to power homes, businesses, and moreover the past few years has grown in popularity.
There are several advantages to using solar power, but one of the unforeseen advantages is that solar panels can reduce the amount of heat that reaches your roof.
In fact, a solar panel array on the roof of your house could reduce the amount of heat that reaches your roof by up to 38%.
Some of the key points I will cover in this article include:
- Heat enters from your roof
- Solar panels can reduce heat to your roof
- Keep heat away from your roof
- Solar panels make your attic cooler
The sun produces energy that we can invert into usable electricity, now we just have to figure out to efficiently and cost-effectively make that happen.
Does heat enter your home through the roof?
Absolutely. Heat enters your home through your roof, and on a hot day your attic can get up to 150-degrees Fahrenheit or more.
Through a process called conduction, heat from the sun warms your roof which then warms your attic and the rest of your home.
While heat can enter your home in other ways as well, conduction is one of the primary ways that the sun heats your home.
If you have an attic at your house, it will trap some of the heat, but even with good insulation much of that heat will find its way into your house. The only way to stop that is to have a heat-reflecting roof or increase your attic insulation.
At my home in Haiti, we do not have an attic and our roof is made of concrete. Throughout the day the sun shines on the roof, and where there are no solar panels, the roof just constantly heats up and transfers that heat down to the rest of the house.
There is a marked difference where our solar panels are and in the amount of heat that they absorb and reflect.
The bottom line is that even in a home with a thick concrete roof, heat is easily conducted from the roof to the rest of the home.
How much more heat could be conducted from a 150-degree attic to the rest of your home even with insulation?
The addition of solar panels to your roof could greatly reduce the amount of heat that gets trapped in your attic and in turn the amount of heat that enters your home.
Can solar panels help to reduce the heat that reaches your roof?
Solar panels, when installed onto your roof, absolutely reduce the amount of heat that reaches it. Solar panels absorb enough of the heat from the sun to cool your roof by up to 5-degrees Fahrenheit, and they also help your home retain heat in the winter.
Since your roof is one of the major ways that heat both enters and escapes your home, this could help increase the efficiency of solar panels.
The question is whether or not simple insulation in your attic could do the same thing.
There are some studies that show that having solar panels on your roof decreases the cost of cooling and heating your home enough to be a consideration in purchasing solar panels.
Others have come to the conclusion that today’s higher-end insulation does as much if not more to keep your home cool.
It makes logical sense that a device that absorbs and uses sunlight for energy would at least provide some cooling to the roof of your house.
Even if you have the best insulation in the world in your attic, there are entry and exit points that leave your home vulnerable to the heat that gets trapped there.
While there are some conflicting studies, it makes sense that solar panels would take away some of the burdens of cooling your home.
Why is it important to keep heat away from your roof?
Heat enters your home in different ways. One of the primary ways is through the process of conduction which means that heat passes through solid material and ends up on the other side.
This is why, in the summer, your attic can get as hot as 150-degrees or more and some of that heat has to leak into your home no matter how good your insulation is.
A good example of conduction is that our home in Haiti is made entirely out of concrete.
On a hot day, when the sun is shining on the home, when you touch the inside wall, you can actually feel that the inside wall in the home is as hot or hotter than the one on the outside.
If this is happening to the outside walls that only take direct sunlight for part of the day, the same thing is happening to an even greater degree on the roof.
To make things worse, the heat continues to pass through the wall after the sun goes down so that the most heat is being felt inside in the early evening and night.
This is the time when your solar panels are no longer producing energy and you have to rely on batteries or a generator to cool your home and these modes of electricity are considerably less efficient than your solar panels.
If heat enters your home in this way, and it does, then anything you can do to keep heat out will help keep your energy consumption down and make your solar panels even more efficient.
For the majority of people, your roof is the place in your home that receives and transfers the most heat because it will see the most direct and indirect sunlight.
If you can keep the heat on your roof down to a minimum, you should also be able to keep your energy consumption down as well.
Do solar panels make your attic cooler?
Solar panels, when installed on your roof, can make your attic cooler. The sun shines on your roof both directly and indirectly almost continuously throughout the day.
This sun that shines on your roof produces heat and that heat transfers from your roof into your attic.
The way that solar panels can make your attic cooler is by absorbing the sunlight that would normally be absorbed by your roof and turning that sunlight into energy.
The face of the solar panels will heat up, but there is extra protection between that panel and your roof, and if your roof is not receiving as much heat, it will not transfer as much heat to your attic.
Many attics can get up to 150-degrees in the summer, or even hotter.
When solar panels are added to a roof, the surface of the roof is cooled because the heat from the sun can be reduced by up to 38%.
That means that there is up to 38% less heat to conduct from the roof to your attic.
This does not mean that your attic will be cooled by 38%, or that you will receive a 38% reduction in your energy bill, but it does mean that your attic will be cooler.
And if your attic is cooler then the heat inside your home will be reduced as well.