00:00The tank water heater burns money in your basement 24 hours a day, keeping 40 gallons hot for the
00:04two showers you actually take. It is one of the biggest energy hogs in the house, and on a sunny
00:08afternoon, the thing that could do most of that job for free is falling out of the sky and landing
00:13on your roof. Your fence, your patio, completely wasted. I built a water heater for about $30
00:19that catches that heat and hands you hot water with no gas, no element, no power bill. The sun
00:24does all the work. You just give it something to heat. Today, I'm going to show you the exact build
00:29the coil of black pipe that turns cold water scalding on a clear day, how to plummet so
00:34it fills and empties in seconds, the one upgrade that keeps the water hot into the evening, and
00:39the honest limits so you use it for the right things. I have run a version of this for an
00:43outdoor shower, and it will genuinely make you jump. Let me build this simple one first.
00:48Then I will show you the physics that makes cold water come out hot. Here is the whole
00:52starter build. Get a roll of black poly pipe. The flexible irrigation tubing sold at any
00:57hardware store, half-inch or three-quarter-inch. 100 feet of it for around $20 to $25. Get
01:03a sheet of plywood or an old board. That is basically it. Lay the board flat and coil the
01:08black pipe onto it in a tight spiral like a garden hose wound up and staple or zip tie
01:13it down so it stays put. Cap one end as your outlet. Put a simple hose fitting on the other
01:17as your inlet. Lean the whole board against a sunny wall or lay it flat facing the sun.
01:22Run your garden hose into the inlet. Let it fill until the pipe is full of water and shut it
01:26off.
01:27Now you wait for the sun. That is the entire machine. A board. A coil of black pipe. $30 and
01:32a sunny
01:32afternoon. One honest thing before you get excited because I would rather tell you now than have you
01:37disappointed. This is a warm season, sun-dependent heater. On a clear day, it is fantastic. On a cold,
01:43cloudy one, it does very little. In a hard freeze, you have to drain it or the water inside will
01:47freeze and
01:47split the pipe. So this is your outdoor shower, your garage sink, your camp setup, your off-grid
01:52cabin, your pool preheat. It is not a code plumbed replacement for the tank that feeds your kitchen
01:57year-round. Use it for what it is brilliant at and it will amaze you. Ask it to run your
02:02house in
02:02January and it will let you down. Fair deal. Now the payoff. On a clear summer day, water sitting in
02:08that black coil will climb past 100 degrees easily and a well-built one will push toward 140, which is
02:14hotter
02:14than most people set their indoor heater. Open the outlet and what comes out first is genuinely hot.
02:19Hot enough for a real shower. Hot enough to wash dishes or hands without touching the gas line at
02:24all. The first time you feel scalding water come out of a pipe that you filled with cold tap water,
02:28powered by nothing but a board in the sun, it reframes what water heater even means.
02:33So why does a coil of cheap black pipe do this? Two things are working together. First, color. Black absorbs
02:39almost all the light that hits it and converts it straight to heat, while white or shiny surfaces bounce it
02:44away. That is why a black car seat cooks you in summer and a white one does not. The black
02:49pipe is
02:49a sponge for sunlight and the water sitting inside it soaks that heat right up. Second, surface and time.
02:55By coiling 100 feet of pipe onto one board, you have laid out a huge amount of black surface in
03:00the sun
03:00while holding only a few gallons of water inside it. A lot of collector? A little water. That water has
03:05nowhere to go and hours to sit there absorbing heat so it climbs and climbs. Thin water, big black surface,
03:11patient sun. That is the whole secret. And it is why the shape matters as much as the color.
03:16People act like this is some new off-grid hack. But it is one of the oldest pieces of home
03:20technology
03:21there is. A man named Clarence Kemp patented the first commercial solar water heater back in 1891
03:26called the Climax. And it was exactly this idea. Black painted tanks sitting in a glass top box
03:32catching the sun. By 1909, another inventor, William Bailey, improved it by separating the collector from an
03:38insulated tank so you would still have hot water after dark. And versions of his design sold by the
03:42thousands in California and Florida before cheap gas pushed them aside. Every solar heater today,
03:48the fancy ones on rooftops included, is running Kemp and Bailey's century-old idea. You are just
03:53building the two dollar a foot version. If you have got a sunny wall in a hardware store nearby,
03:58hit subscribe. Because building the thing that quietly replaces a utility bill is the entire point of this
04:03channel. And members get first look at the bigger off-grid and money-saving builds before they go
04:08public. Free subscribers still get every one of these. Now here is the upgrade that fixes the one
04:13weakness of the simple coil. The plain coil has a problem. The second the sun goes down, the thin water
04:19in the pipe cools off fast. Because there's so little of it. The fix is to add storage and a
04:24cover.
04:25And this is the leap from a toy to a real system. Take a metal or dark plastic barrel, paint
04:30it flat black,
04:31and build a simple box around it out of plywood with an old window or a sheet of clear plastic
04:35over
04:36the front. Now you have two things. The black barrel holds many gallons instead of a few,
04:40so it stays hot far longer after sunset, into the evening when you actually want to shower.
04:45And the glass on the front creates a greenhouse. Sunlight passes through the glass, hits the black
04:50barrel, turns to heat, and that heat gets trapped under the glass instead of blowing away in the wind.
04:55Trapped heat plus a big black tank equals hot water that survives the evening.
04:58This is the batch heater. And it is the design that ran real households for decades.
05:04Here is the trick that makes it flow without a single pump. It feels like cheating. Hot water rises,
05:09cold water sinks, always. So if you mount your storage tank higher than your collector,
05:14something beautiful happens on its own. The sun heats the water in the collector,
05:17that hot water rises up into the tank, and cooler water from the bottom of the tank slides down to
05:21take
05:22its place and get heated in turn. The whole system circulates itself all day using nothing but the fact that
05:27hot
05:27water floats. It is called a thermosiphon, and it means no pump, no electricity, no moving parts to
05:33break. You set the heights right once, and then gravity and heat run the machine forever. A couple
05:37more moves worth knowing. Insulate every pipe that carries your hot water away from the collector.
05:41Cheap foam pipe sleeves, because it is heartbreaking to heat water for free and then lose half the heat
05:47in an uninsulated run to the shower. Second, if you build the batch box, tilt the glass face toward the
05:52sun,
05:52rather than standing it straight up, roughly facing the midday sun, and you will catch far more energy
05:57across the day. And one safety note I will give you, straight and then move on. Water that sits warm
06:02and stagnant for a long time can grow bacteria. So this is a use it and flush it system. Not
06:08a tank
06:08you let sit for weeks. Run fresh water through it, use it, drain it before a freeze. Treat it like
06:13the
06:14seasonal tool it is and it stays clean and safe. So here's the whole thing. For $30, coil 100 feet
06:20of black
06:20poly pipe on a board. Fill it and let the sun cook it hot enough for a shower by afternoon.
06:26When you want it to last into the evening, wrap a black painted barrel in a glass front box for
06:30storage and a greenhouse effect. Mount the tank above the collector so it circulates itself with
06:34zero power. And insulate the hot runs so you keep what you caught, drain it before a frost, use it
06:40fresh
06:40and point it at the sun. That is a water heater that costs nothing to run, built from a hardware
06:45store
06:45pipe. And the same idea a man patented before cars had engines. If the idea of scalding water
06:50coming out of a pipe you filled with cold tap makes you want to build one this weekend,
06:54share it with the person you know who is off-grid, camping, or just tired of paying
06:58to heat water they barely use. See you in the next one.
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