Do Solar Panels Make Your House or Building Hotter?

Many wonder: “Do solar panels make my house hotter?” It’s an understandable concern—solar panels are dark, sit directly under the sun, and cover large parts of the roof. At first glance, they look like they'd trap more heat.

The truth is the opposite: solar panels can actually help keep your home or building cooler. By shading your roof from direct sunlight and allowing airflow between the panels and roof surface, they reduce the amount of heat that enters your home/building. Let’s take a closer look at why.

Do Solar Panels Generate Heat?

Yes, solar panels do warm up under the sun—much like your car’s roof or windows. On hot days, surface temperatures can reach 40-60°C.

But here’s the key difference: solar panels absorb sunlight as photons, not heat. A portion of that energy is converted into electricity, while the rest dissipates as heat naturally.

This means that while the panels themselves get hot, they still absorb and retain less heat than a bare roof exposed directly to sunlight. In tropical climates like Singapore, bare roof surfaces can reach extreme temperatures within hours on a clear day, radiating heat into the building. By covering the roof, solar panels both generate electricity and provide shade, helping reduce indoor heat transfer.

Can Solar Panels Keep Your Roof Cooler?

Yes. A study from the University of California found that solar panels can lower a roof’s surface temperature by roughly 38%.

Here's why:

• Shade effect: Panels absorb the sun's rays and prevent them from heating the roof directly.
• Airflow cooling: The small gap between panels and roof creates a convection current that carries hot air away.

Together, these effects mean that solar panels serve as both an energy source and a form of passive cooling for your home or building.

Flat vs. Pitched Roofs: Does Roof Type Matter?

Pitched Roofs (common for landed homes) already allow hot air to rise and escape. Installing solar panels add another protective layer of shade.

Flat Roofs (common in HDB, schools, and commercial buildings) often deliver an even bigger cooling benefit. Raised mounting structure create more airflow beneath the panels, boosting ventilation and reducing heat transfer.

The Bigger the Roof, the Bigger the Benefit:

For larger commercial facilities, the cooling effect of solar panels can translate into significant operational savings—even when insulation is already in place:

• ‍Cold rooms & warehouses: Panels reduce direct heat gain, helping maintain stable temperatures inside.‍
• Offices & schools: Less roof heat transfer means lighter demand on air-conditioning.‍
• Shopping malls & function halls: Wide, flat roofs gain maximum shading + airflow benefits, lowering cooling loads across large spaces.

In Singapore, where air-conditioning often accounts for the largest share of electricity costs, this hidden advantage of solar panels can be just as valuable as the power it generates.

Additional Cooling Combinations

Solar panels can also be paired with other smart solutions to maximise thermal comfort and efficiency:

• ‍Green roofs: Vegetation absorbs heat while solar panels provide shading.‍
• Solar-reflective coatings: Bright-coloured paints (eg. white) reduce roof surface temperatures, complementing the solar panels.‍
• Solar thermal systems: Solar heating systems capture excess heat to provide hot water, easing energy strain on HVAC and boilers.

These combinations make homes and businesses more energy efficient and more climate resilient, vital in Singapore's hot, tropical climate.

The belief that solar panels make your home or building hotter is a myth. In fact, they do the opposite: by shading your roof and allowing ventilation, solar panels help keep buildings cooler and more comfortable.

For homeowners, this means a cooler living space and potentially lower air-conditioning bills. For commercial properties, it can reduce cooling loads and deliver meaningful operational savings over time.

When you install solar, you’re not only producing clean energy — you’re also adding a protective shield to your roof that supports your comfort and energy efficiency.