Why is it difficult to make smartphones with inbuilt solar panels to automatically charge themselves?

Many would have wished their smartphones had inbuilt solar panels that would charge their phones automatically so that they would never run out of battery and save us some costs when it comes to paying electricity bills.
But integrating solar panels into smartphones to enable automatic charging presents several challenges:

1. Efficiency of Solar Panels:
Current solar panel technology is not highly efficient, especially in small sizes like those that would fit on a smartphone. This means the energy harnessed from sunlight would be minimal, providing only a small fraction of the power needed to run a smartphone.

2. Size and Surface Area Limitations:
Smartphones are compact, limiting the surface area available for solar panels. This small surface area can’t capture enough sunlight to significantly charge the phone’s battery, especially when compared to the energy demands of modern smartphones.

3. Indoor Use:
Smartphones are often used indoors, where solar charging would be even less efficient due to lower light levels. This limits the practicality of solar charging for everyday smartphone use.

4. Design and Durability Concerns:
Integrating solar panels into the phone’s design poses challenges. Solar panels could make the phone bulkier or more fragile. Protecting the panels from damage while maintaining aesthetic appeal is a significant design hurdle.

5. Cost and Manufacturing Complexity:
Adding solar panels to smartphones would increase manufacturing complexity and cost. This might make the phones more expensive, affecting their marketability and accessibility.

6. Variable Charging Conditions:
Solar charging depends heavily on the availability of sunlight, which varies based on weather conditions, geographic location, and time of day. This inconsistency could make solar charging unreliable as the sole or primary charging method.

Though the concept of solar-powered smartphones is appealing for its sustainability, the technological, practical, and economic challenges currently make it difficult to implement effectively. Advances in solar panel efficiency and design may gradually overcome some of these obstacles in the future.