Elias Yoder has reported:

A black garden hose left in the sun can heat water enough to cause a burn, and a video uses that everyday experience to explain how to make a low-cost solar water heater. The basic design uses 100 feet of black polyethylene pipe, a board and a hose fitting to capture the sun’s heat and retain the hot water instead of letting it run onto the ground.

The video says the collector should be positioned where it will receive sunlight, angled rather than laid flat, and kept clear of shade, including from trees as they grow. It explains why the pipe should be black and coiled, and warns against closing both ends. Opening the tap at noon can send fresh, cooler water into the system and effectively restart the heating process for the afternoon.

A bare coil is described as suitable for washing, not showering. One hundred feet of half-inch pipe holds about one gallon, enough for a bucket, basin or wash, while a shower can use a couple of gallons per minute. For a shower, the video says, the design needs a barrel inside a glazed box, with a flat-black surface rather than a glossy one. It also covers using a thermosiphon to circulate water without a pump or electricity, insulating the connecting pipe and tilting the glass.

The water may become dangerously hot. At 140 degrees, it can burn an adult’s skin in seconds and injure a child faster, the video warns. A glazed collector can reach that temperature on a clear day, so the hot water must always be mixed with cold water before use, with no exceptions for children. The video calls the system wash water, not drinking water, and says warm standing water makes a shower the riskiest use; it outlines two ways to address that risk.

The build also needs a drain plan for freezing weather, which the video says should be decided during construction rather than after the first frost. Its creator says the first use he would prioritize on a farm is unrelated to washing, though the description does not identify that use.

The video places the idea in a longer history. Clarence Kemp patented a commercial solar water heater in 1891, using black tanks in a glass-topped box. In 1909, William Bailey separated the collector from an insulated tank so water remained hot after dark; the systems sold in the thousands until inexpensive gas displaced them. The video says modern rooftop systems use the same principle.

The creator invites viewers to comment on what they would use their first heater for and, for newcomers, how many clear sunny days they get in a year, saying that figure determines whether the system is a toy or a tool where they live. The description ends by teasing “the other way” in the next video.