How well do the solar lights in porta potties actually work at night?

The solar lights in standard portable toilets provide a noticeable glow inside the unit at night, but they are not bright enough for clear visibility. They are designed as safety lights to help users orient themselves, not as reading lights.

A single small solar panel on the roof charges a battery during daylight. On a sunny day, the battery charges fully for several hours of operation after dark. On a partly cloudy day, the charge is weaker and the light may dim sooner or last a shorter time. The light typically uses an automatic light sensor to turn on at dusk and stays illuminated until the battery drains, which is often a few hours but can be less with insufficient sun.

The light emits a soft, ambient glow from the ceiling. It is enough to see the general interior shape and locate the toilet seat, but details like a dropped item or the toilet paper dispenser may be hard to see clearly. For your event of 60 people in a dark park corner, the solar lights will prevent total darkness but you should not expect bright, shadow-free lighting. Adding a battery-powered LED lantern inside or a nearby exterior light post would significantly improve visibility for guests.