Imagine you have a natural stream running through a low-lying area on your farm. It’s a great source of fresh water, only you really need it to irrigate some crops sitting at a higher elevation. The ...

Physics spoiler alert: There are actually two methods to move water that don't require an external power source—but that’s not the same thing as running on free energy. The first method is the siphon ...

We independently review everything we recommend. We may get paid to link out to retailer sites, and when you buy through our links, we may earn a commission. Learn more› By Thom Dunn Thom Dunn is a ...