How shade impacts on home solar performance

Solar panels work by capturing direct sunlight and converting this into electricity

Solar panels work by capturing direct sunlight and converting this into electricity.

Published Jun 2, 2023


Solar power systems are in high demand as homeowners look to protect themselves from ongoing loadshedding and benefit from government’s home solar tax incentive.

However, one factor that is often overlooked when considering a solar investment is the impact of shade on their performance.

Understand your roof’s solar potential with LookSee’s free Solar Score

LookSee's executive head, Marc du Plessis explains: “Many homeowners start their solar journey by looking at the various systems available on the market. However, it’s best to consider your property first. In fact, your home’s structure determines how successful your solar installation will be in generating electricity for your family to use.”

It’s for this reason that Standard Bank’s home management platform, developed South Africa’s first, free, online Solar Score for residential properties to help homeowners easily understand the generation potential of their roofs.

Got shade?

Shady conditions are one of the factors that can significantly reduce the efficiency of solar panels and ultimately lower the amount of electricity produced.

“Solar panels work by capturing direct sunlight and converting this into electricity. When solar panels are shaded – even partially – the amount of direct sunlight they receive is reduced, which has a significant impact on the overall performance of a solar panel system,” says du Plessis.

Shade can come from various areas such as trees, buildings, and surrounding mountains. It’s important to see how much shade your roof will experience and whether there is anything you can do to remove or minimise the causes. Bear in mind that as the sun moves across the sky, the areas of shade will change too. You’ll also need to take into account that the sun’s position changes with the seasons, and this could also have an impact on the extent of shaded area.

Free roof assessment

If you’re not keen on spending the day watching your roof for shade, then the LookSee Solar Score is for you.

This easy-to-use system only requires your physical address to assess the structure against a variety of factors that will impact the performance of a solar solution. These include the direction the various roof panes face; the slope and available roof area on optimal panes; radiant power from sunlight; and shady conditions from surrounding buildings or vegetation.

“The LookSee Solar Score is the first of its kind to provide this level of insight into South Africa’s residential properties, helping homeowners to take the guesswork out of their solar decisions. Not only do we provide a score on the home, but we also reveal valuable information such as usable roof area, average days of sunlight, energy generation potential and how much a homeowner could save on their electricity bill,” says du Plessis.

Homeowners can experience the Solar Score by going to

Please note that the Solar Score is currently available for most of South Africa’s large metro’s with sectional title properties currently excluded. Sectional titles and more cities and towns will be added during 2023.