Why solar carport projects are so cool (literally!)
Over a thousand Sun Exchange members have purchased solar cells that will provide affordable and clean energy to a thriving community of families living in two apartment blocks at Tafelsee Apartments, in Cape Town, South Africa.
This project is unique in that it’s the first Sun Exchange solar project that utilises a carport solar structure. There are quite a few stand out features and benefits of this type of carport solar project which you may find surprising and the aim of this blog is to inform and educate on these kinds of solar projects..
So, firstly, what is a carport? A carport solar plant is where the solar panels are mounted in a ground mounted structure, where the panels then act as a canopy for cars to park underneath. Here is an image of how the solar array will look at Tafelsee Apartments.
This type of solution has multiple benefits, particularly suitable to dense urban environments such as these. The benefits of a carport system are:
- Apartment blocks have very little roof space. In the case of Taflesee Apartments their roof space is used as a communal laundry/clothes drying area. The roof is therefore a no go for solar panels. The apartment blocks have a large car park area, which provides ample space for deploying solar panels onto. Raising the solar panels up above the car park means land is being used that is already developed, so that valuable urban green spaces can be preserved.
- The solar panels themselves create shade for cars parked underneath them. This is really beneficial in a city as sunny and hot as Cape Town. Air Conditioning systems in cars use a lot of energy, so keeping cars cool when parked not only improves comfort when the passengers enter the vehicle, but it will also reduce local exhaust fume emissions and help avoid build-up of those unsightly ‘air-conditioning puddles’ that you often see in car parks.
- The presence of a solid structure and the solar panels situated in the car park, sets the project up nicely to later retro-fit electric car charging points.EV car sales continue to grow globally, with some suggesting that they will surpass internal combustion engines by 2025. South Africa is starting to set up the infrastructure required to support this new technology. Being ahead of the curve means carports will enjoy the first to market luxury of cost effective clean energy generation.
- As the solar panels are up off the ground, with a lot of air circulating around them, the solar panels performance is boosted. Solar panels fixed to roofs or close to the ground suffer power output losses due to the heat that is absorbed and then radiated into the solar cells which increases the solar cell temperatures, increasing resistance in the cells and thereby reducing efficiency. Getting the solar panel a few metres up off the ground is an ideal way to keep the solar panels cool.
- Solar panels installed on carports are easier and cheaper to clean. Just as solar cells don’t like heat, they also don’t like dirt. In dry environments, dust and dirt can gradually build up on solar panels, causing a gradual and noticeable drop off in power output. Solar panels on roofs are difficult and dangerous to get on for maintenance. Especially when it comes to cleaning, usually there is a cost/benefit ratio calculation undertaken with solar projects to determine the point where cleaning solar panels will increase the power output sufficiently to justify the cost of cleaning the solar panels to boost output. Fortunately, dust build up is something that is checked for at the site survey during the solar project development phase. Sun Exchange’s solar engineers factor in this cleaning schedule against cost of doing so vs power output, finding the optimal balance between operating costs and power output. As carport structures are so much more easily accessible, the cost of cleaning them is greatly reduced, so it makes more sense practically to keep them free of dust and bird poop which can hurt the project's bottom line. Similarly, although solar panels are designed for 25 years and very little can go wrong with them, having them closer to the ground makes access for fault finding and replacing parts just that much easier, reducing downtime in the event of something going wrong with the system.
So there you have it! That is carports! Carports are more expensive to install as they require more robust fixings and take longer to erect. However, hopefully you can see from the above that this extra effort is absolutely worth it and don’t be surprised if you see more Sun Exchange carport solar systems on the platform in the future.