Storing rechargeable solar lights in your horse trailer will help to make nighttime trailering a breeze. When you’re at an event or on a daylong trail ride, leave the rechargeable solar lights out in the sun all day and they’ll be fully charged for nighttime use. Be extra smart and buy the motion-activated solar lights so you don’t have to worry about turning them on and off. Purchase a pack of three on Amazon.com for under $30.