Heat absorption by solar panels can reduce efficiency. Likewise, the transfer rate can be less if a solar panel is too cold. Several benefits you may also wish to gain from solar panels absorbing heat, so we will look at how you can use them to good effect and maximize your solar panels.
A few of the points we’ll cover include:
• Do solar panels absorb heat?
• How solar panels cool homes
• What convection currents are
• How much savings can solar panels provide on cooling and roof repair costs
• How solar-power air conditioners work
We’ll also discuss similar details about how solar panels work, such as their cooling benefits for homes in the summertime.
Do Solar Panels Absorb Heat?
Yes. Although solar panels generate electricity from sunlight, not heat, they absorb heat nonetheless, as one might expect from an object that relies on absorbing the sun’s rays to function.
Solar panels suck up the maximum sunlight possible from the environment by their design. Think about some time when you’ve made the mistake of wearing a black shirt in the hot sun when you should’ve worn white – it can get quite warm, right?
That black t-shirt is not, of course, generating electricity like a solar panel. Still, the same principle applies – namely, sunlight generates heat in an object that absorbs a lot of it (like solar panels, which are blue or black, other dark-colored objects absorb more heat than light-colored ones).
How Solar Panels Cool Homes
The good news for homeowners is that solar panels provide an extra protection barrier, absorbing heat before it hits the rooftop and has a chance to make its way into your home.
One of the under-appreciated benefits of solar panels is their cost savings to homeowners who would otherwise rely on air conditioners to cool their homes in the hotter months.
If you haven’t ever worked as a roofer, you might not appreciate just how hot rooftops can get under the glaring sun. Rooftop temperatures in July and August can frequently exceed 160+ degrees Fahrenheit.
Rooftop heat conditions can be so severe that the Occupational Safety and Health Administration (OHSA) sets strict guidelines to protect roofers’ safety. Heat strokes are not uncommon in the profession.
The materials comprising roofs are designed to withstand the heat and repel it upward, but even so, no matter how well insulated your home is, some heat inevitably leaks inside and raises the indoor temperature.
See also: 13 Advantages + 5 Disadvantages Of Solar Energy
Convection Current and How It Cools A Home
A significant amount of the heat that solar panels absorb passes into the wider environment (saving your home from exposure) via a current convection process.
A “convection current” refers to the air movement between the solar panels and the roof. This air carries a significant portion of the heat from the solar panels, so it never has the chance to make headway into your home.
Solar panels have tiled arrays and have even more space separating them from the actual roof for convection currents to do their thing, whisking away even more unwanted heat. More efficient solar panels translate into greater cooling effects because inefficient conversion results in greater heat buildup on the panels.
Higher-quality solar panels that are better at turning sunlight into electricity operate at lower temperatures than lower-quality ones.
Heat Reduction Solar Panels Achieve on Roofs
Let’s look at an impressive study performed by researchers at the University of California San Diego to quantify how effective solar panels can reduce roof temperatures.
They measured the heat reductions provided by solar panels and found that they reduced the surface temperature by as much as 38% — more than one-third.
Several factors affect the actual number on a case-by-case basis, such as how the solar panels are positioned on the roof, the surface area they cover, the type of solar panels, and the roof’s architecture.
Benefits of Solar Panels For Roofs
In addition to keeping roofs cool in the summer, solar panels protect them from wear and tear. For example, depending on the climate, your roof may be susceptible to a phenomenon known as a thermal shock that can do a number on its integrity over time.
Thermal shock occurs when high daytime temperatures cause the materials in the roof to expand. Then, after sundown, the temperature cools considerably, causing the materials to contract.
This can eventually result in gaps in the roof and warping – obviously not good for your home or wallet.
- Large repair jobs on roofs in the US tend to cost, on average, between $1,500 and $7,000 – money that you would likely find better uses for than constantly having to invest in roof fixes.
Solar panels protect roofs, at least to a certain degree, from the thermal shock phenomenon by preventing the rooftop temperature from getting too high during the daytime and holding in some of the heat after sundown to stop the temperature from falling too rapidly and contracting the roof materials.
In the long run, this can add several extra years of life to your roof and, as a result, save you potentially thousands of dollars in costly calls to the roofing company.
Solar-Powered Air Conditioners For Even Greater Energy Savings
We’ve already discussed how solar panels simply eliminate costly air conditioning requirements by their heat absorption. But you can also take your savings to the next level by installing solar-powered air conditioners to eliminate your AC bills next summer potentially.
- According to data from the U.S. Energy Information Administration, air conditioning represents roughly 12% of all home energy use – and it’s even higher (as high as 27%) in hot climates. That amounts to, depending on the size of your home, many thousands of dollars each year.
That adds up to roughly $29 billion in AC costs to American homeowners yearly – a lot of money. When we’re talking about such large figures, it’s easy to understand how, over time, solar panels can pay for themselves and then some by chipping away at these costs.
Solar-powered AC systems are now available as either stand-alone units for single power rooms or system-wide HVAC systems that ventilate your entire house.
In addition to shaving down energy costs, harnessing the sun’s natural power to cool your home is also beneficial for the environment. It reduces your carbon footprint by eliminating reliance on fossil fuels for energy.
Sources
- https://www.researchgate.net/publication/251496714_Effects_of_solar_photovoltaic_panels_on_roof_heat_transfer
- https://www.osha.gov/news/newsreleases/region7/11102016-0
- https://www.eia.gov/todayinenergy/detail.php?id=36692
