Yet another reason to love the sun: it’ll keep your car’s battery charged. Just plug this helpful 15-watt solar charger into your vehicle’s 12V lighter socket and position the panel to pick up the most daylight possible. The powerful 15 watts means you can use it for boats or larger vehicles too. You can also charge batteries to run lights, TVs, VCRs or other small appliances. Blue LED light shows it’s working. Works on cloudy days too.