Solar energy technology is becoming more and more accessible thanks to developments such as portable solar panels that you can use to power your devices. That’s why solar-powered phone cases seem compelling. Not only would they provide a clean power source for the gadget you use most, but they would also mean you’ll almost always have a way to charge your phone – no more carrying around cables or portable chargers.
Several projects are underway, including one from iPowerUp which claims to be the “world’s first smart solar box”. However, a study published in The International Journal of Life Cycle Assessment indicates that solar power will not make traditional phone chargers obsolete in the near future. Researchers from the University of Klagenfurt in Austria compared the two charging methods and found that “the external battery works significantly better than the solar charger.” This is based on cumulative energy demand (CED), which calculates the amount of energy consumed by a product throughout its life, from the time resources are extracted until the user throws it away.
In terms of efficiency, the power bank is also a clear winner with a charging efficiency of 64.77%. This may seem low, but it is normal for energy to be lost during the conversion and transmission process, and it is much better than solar chargers. The researchers found that the efficiency of the panel was around 10%, with that of a single cell being around 12%. Additionally, solar panels are (of course) affected by weather conditions, so solar chargers are significantly less useful on cloudy or dark days.
Why solar power won’t overtake chargers anytime soon
Of course, one of the main appeals of a solar phone case is clean energy, which is a noble goal. However, according to the Austrian researchers’ calculations, it would take almost 10 years for a solar charger to reach energy payback time (EPBT), the point at which the device’s energy output exceeds the amount of energy needed to produce it. Both types of chargers require a lot of resources to produce, but solar chargers have a similar, if not higher, environmental impact than power banks, which seems counterintuitive.
This doesn’t mean that iPowerUp’s case won’t work when it’s released. However, one of the major problems, and the reason why solar panels have taken over the calculators and not much else, is that the size of the panel is related to the amount of energy it can produce. Creating one small enough to fit on a smartphone and powerful enough to keep the device running long term would be incredibly impressive.
Solar technology is advancing as researchers discover new ways to make panels more efficient and cheaper to produce. A newly published study shows that solar power is not weak, but rather being ruined by fossil fuels, indicating that solar performance could actually improve by switching to greener energy sources overall – and moving away from coal and oil. Yet even if the type of micro-solar panels that iPowerUp claims to have developed are possible to produce now or in the near future, the numbers clearly show that solar power is not yet good enough to completely replace phone chargers.
