Some security lights need extensive cabling, so they can be complicated and disruptive to install. If you're installing lights on your property retrospectively, you might run the risk of damaging masonry, rendering, or woodwork. Mains powered lights can also have financial and environmental implications, considering their power consumption.
Solar-powered security lighting is a wonderful alternative. It's easy to install, because you can fix the fittings to any surface without wires. The solar panel uses the sun to charge the internal batteries during the day. At night, a charged battery will be enough to illuminate the lamp. As most solar security lights have PIR, they only switch on when they sensor movement, so they're efficient with no running costs.