A homemade storage tank can have the life-expectancy of a sea tortoise, even if it's made of wood. The tank must only hold the water's weight, and the liner will keep the wood dry. Yes, liners are available that hold hot waters. Just put on your miracle-working power, and give the command, "Liner, drop thyself into that thar box crate," and it shall be done for you, just as soon as you drop it in with your own two hands. It's as near a miracle as one can get. If only it could be as easy to get hot water to drop into that thar crate.
If liners cost too much, the purchase of liner membrane alone, not to any particular shape, should be less money. Just drop the membrane like a tarp into your wood crate, and cut the excess along the top of the crate. Or don't cut it, because, if a tank of a different shape / size is decided upon later, the membrane might still be usable for it. Just google "tank liners" or "pool liners" or "pond liners." Some selling these things may also sell high-temperature liners.
There are thin and cheap plastic sheets sold everywhere to face tub and shower surrounds. It's cheap because it makes for the most-basic look in a shower, and so prices are accordingly. End-time corporations want too much for their products, so we fight back by making our own. Back to make-shift we go, it's so much more human, anyway.
What about using foam insulation in the tank (available at Home Depot)? The foam is water proof, and made to withstand the hot summer sun beating down on a house wall. Paste it to the inner crate, and silicone the corners. We have just saved the cost of a liner because we needed insulation anyway. We win, the liner manufacturer loses.
You may agree that a wood tank in an attic should have a liner, just in case, unless you don't value the ceiling much below the tank. The liner can go behind the foam insulation. I don't see why standard vapor barrier can't be used. It's under a dime per square foot. Siliconed corners do not want the crate's frame to shift. Screw the plywood well. Don't push the tank around from the top, but from the bottom. Apply the silicone at the tank's resting place. Do a double or triple coat of silicone. I will guess that it sticks excellently to foam insulation. I'm not sure how well window-grade silicone will do submerged, but I do know that silicone is used in aquariums.
Insulating with regular pink within the 2 x 4 frame is easy enough, and the rest of the bag won't go to waste since you'll be in the attic anyway. Apply an insulated lid of some sort with some means of a good seal. The lid can be a piece of unwarped plywood covered in foam insulation on the inside and out, but with some vapor-barrier material wrapped around the plywood before the foam goes on. Your lid is now water proof, and it didn't cost you $40. There must be something heavy in the garage or attic that's no longer used, like that old sewing machine that grandma passed down to the kids. Sit it on top of the lid and save more money as compared to buying a clamping mechanism. There needs to be an air hole to allow water levels in the tank to change without obstruction, but if the lid isn't air tight, it will act partially or fully as that hole.
We're not finished here, ladies. Don't get excited yet. I know how easy and carefree it is to just throw on any old lid for the tank, and be done with it. But if you don't want pieces of flies in your hair through the shower head, arrange to keep them out of the tank. A lid with just a little crack may allow more than flies in, and likely their eyeballs will get through. You don't want that kind of silky-smooth hair. The good news is, drowned flies may float and not get to the exit hole of a storage tank; the bad news is, spiders can sink to the bottom and be amongst the first out of the tank. Now you're starting to see the light in that heavy sewing machine.
If only you could learn to use one, the world will start to go back to normal again. My mother once dazzled me with her sewing machine; she was good. But I haven't seen her on it since the feminists came out with their swords.
Don't imagine all is wonderful in that tank when in reality it may be a yeast's wonderland. Feed that thar crate some bleach now and again, another cheap fix.
Aside from the piping, you're done. I know it's too hard to believe. In the world of globalist forces, it should soon be against the law to make your own hot-water tank this cheaply. Don't kid yourself; globalist forces are scheming right now to capitalize on the green-energy market that's being rammed down everyone's throat. They have elaborate plans for us.
If you opted, in the last chapter, for a heater tank on the roof with water pressure, you need the top of the attic tank no higher than the highest water level in the roof tank. The latter tank must have an automatic shut-off valve, or it will cause the attic tank to overfill. One can get an automatic shut-off valve, the ones for toilet tanks, at Home Depot for under $20, but I don't know whether they work properly at the angle of your roof. There should be other types available. I'll show you how to prevent roof-tank waters from entering the storage tank until you want it.
If both tanks have equal volumes, they will always be at the same level when water is permitted to be shared. Gravity provides both tanks with an equal water level. The pipes should enter both tanks at their bottom halves.
There are summer nights where the attic is very warm into half the night, in which case any waters left in the storage tank, in the morning, may be appreciated for face washes and shaves. There is a very big question on when or how to feed the storage tank with roof-tank waters? If the attic tank already has water that's cold, we do a disservice to the roof water to drain it to the attic tank. That's the problem in having the two tanks passively connected: cold can get mixed with warm. We've go to find a way to prevent this.
There is only one solution: to forbid the passage of cold water from tank to tank. One way is to get some sensor that I aim to hunt for when I get around to it. In the meantime, you can hunt for one. The sensor takes the temperature of the water in the tank, and is made to open a valve only when the temperature is high enough. If the valve is closed, no one gets to have a shower using water from that tank. It may not be an ideal situation, because some roof water warmed up is better than sheer cold, yet for not wanting to mix roof water with attic water, the person wanting some roof water can't get any.
The cockpit situation can now be emphasized for its advantage over the device above. The cockpit system includes a pipe from the roof tank's outlet. It brings warm water to a manual valve at the tub wall or ceiling. No water is permitted to enter the shower stall from this valve. Instead, the water on the other side of the valve goes back up, now to the attic tank. We can call this the tank-to-tank pipe.
If you decide to use the cockpit, it's risky without an automatic shut-off valve (in the roof tank). First of all, if you leave the tank-to-tank valve open while not shutting the cold pipe to the roof tank, the attic tank will keep on filling. You can prevent a flood with a drain at the top of the attic tank, and you could feed that drain to the tub so that someone will eventually discover that the water is on continually, but there is another way to create the same bad situation, and you may not want to take the risk, even if your pump (low-pressure) is taking water from a lake or river that never goes dry.
If one shuts the cold pipe to a sealed tank, then allows it to drain, air needs to enter the tank, or it won't drain. One can use a one-way valve to let air in, but how does one get the air back out when refilling with water? If one arranges a valve (operated at the cockpit) that lets air back out, why won't water go out the valve too? One needs to wait until he/she thinks the tank is filled back up, then shut the air valve, or water will continually go out until someone realizes it, which can burn out the pump if it's not taking water from an infinite / large supply. If you're on solar electricity at the time, it could drain the entire battery bank, very bad for the batteries. Plus, if you have the drain going to the tub in hopes that someone spots or hears the water running, it could be many hours afterward, and all that time the septic bed (if you even have one) has been getting drenched with water. There is a solution, which I'll show later in this section.
The alternative way to stop water from going out the air valve is to employ the automatic shut-off valve, with an air hole at the tank's top, above the water level.
The attic tank needs no automatic shut-off valve if there is one in the roof tank. The attic has got to be fed by gravity alone.
If the roof tank is sealed while having the automatic shut-off, there's the benefit of the tank acting like a pressure tank. As it fills, air within it gets compressed. The problem is, compressing air at 14 psi to half its volume gets a pressure at 28 psi, probably too much for your tank. Use a low-pressure pump (won't get the air to 28 psi), then install a valve at the top of the tank, with a pressure gauge attached. Leave the valve open as the tank fills, but close it at a certain time when much of the air has been removed by the incoming water. Decide the maximum pressure that you want in the tank. When the gauge shows that pressure (as the water continues to enter), re-open the valve and let some air out, then close it again. Repeat until the tank is full; we can let more air out if we choose at that time. Or, drain the tank some and repeat the process to get a higher pressure. We then won't need to let air back into the tank over an over again. After we have it the way we want it, the air in the tank will always remain.
If the tank operates fine for a while at the pressure of your choice, the temptation will be to increase the pressure. It's your call. How will you assure that you don't choose a pressure too high? Maybe go up by 1 psi at a time, trying each out for a few days / weeks, and hope you don't go too far. If it only springs a leak, no problem, just don't crack the plexiglass.
The drawback to having pressure is that it will likely use more water per unit time, unless everyone resists the temptation of having the showerhead valve on at full force. Pressure makes showers feel good, and feel good means an extra minute or two in the shower. Something to think about. If the water drains by gravity, you can slow it down by closing the air-inlet valve a littler more. It would be very nice to choose how fast it comes down. You could have two valves at the cockpit to control two air-inlet valves, one left open wide, the other restricting flow for when more people than usual want showers on the same day.
Water gets "wasted" while people soap themselves over, but they have the choice of shutting the showerhead valve off while doing so. I've done it. Fifteen seconds is enough to get wet all over, and I'm done (one hair wash) in a minute or less total shower time (long hair may need a little longer).
Okay. You are standing in the tub, and the device on the wall or ceiling tells you that the attic tank is on the cool side, not to your liking for a shower. Yes, there needs to be a thermometer in the attic tank to indicate the temperature, through a small electrical wire (or wireless), on a device at the floor of your choice, and preferably in the shower stall. The cockpit (always located at the shower stall / tub) has another valve on the wall or ceiling, and this one is attached to a drain pipe coming from the bottom of the attic tank, which drains the tank.
Wonderful. And if the water is semi-warm or tolerable, one can wash feet and legs with it, not letting it go to waste, requiring less water (warmer, hopefully) from the roof tank to finish the shower. One does not feel cold in a shower when washing legs so long as the upper body is dry. It seems fairly obvious that this drain pipe should come in low on the shower wall, as it's purpose is to get rid of cold water down the drain. Or, if you are concerned about having too much water in the septic system, route this drain pipe to the outside.
We have a second valve in the drain pipe, which opens water to the showerhead. Wow, that was easy. Instead of opening the drain valve, we open the showerhead valve that comes in the pipe just before it. It's a miracle. Okay, it's not exactly ingenious, but necessary unless you want to go nuts with the ever-changing water temperatures. To let water go down the drain instead of up, open both valves.
When you turn on the showerhead valve, no water flows from roof tank to attic tank. You have that choice, however, to open the tank-to-tank valve while the attic valve is open, allowing the two tank waters to mix while they are coming down the one pipe. That means you need a thermometer in both tanks to help you with the decision on whether to mix waters at any time, and of course our cockpit was two temperature displays, one for each tank. The only other thing needed is a little music, or some birds chirping.
There is more you can add to the cockpit for when the roof water is not very warm, and you do not want more cold water to enter it. For this one, you bring a pipe out the bottom side of the roof tank, on the opposite side from the cold-water end. And you must arrange for the cold pipe to come first to a valve at your cockpit that you can call the Boss valve. You can shut the boss off at anytime, which prevents water from entering the attic tank. When the boss is off, you can have the entire roof waters without cooling them, a very big bonus. When the tank-to-tank valve is open and the boss is shut, you can have a soundtrack with angels strumming their harps. You get the warmest (top) waters last, which, of course, you will give to your wife. All is well.
Find the spot where the attic tank will sit after the necessary considerations. One important consideration is locating it as close as possible to a sun-bathed roof surface. You can build it into a closet that has the roof as one of its walls. It will get hot in that closet, very hot. Do we even need the roof tank if this closet situation works great? If the roof tank is right outside this closet, all the better for piping purposes, but don't put the closet directly under the roof tank for obvious reason (blocks sun to the closet).
You can now insulate the closet walls (but not the roof wall), with the choice of removing the insulation from around the tank, or at least from the tank wall facing the roof. You really do want heat from the closet to get into the tank.
Should you locate the attic tank over the shower / tub walls? Not if you think your house may be the one for your trib retreat, because a water mixer tank would go better directly over the shower. What? Another tank? Come on. Well, there actually was an evil above. Draining the attic tank can be an awful waste of water. If it has been sitting all day without sun, it's going to be a whole tank of unwanted waters until the sun heats up the attic again. Let's say that the sun is out in full force with the attic tank cold. The roof tank gets hot by afternoon, but the attic tank is only 70-80 degrees by that time. It's a great time to mix the waters to get the perfect temperature.
With the mixer tank, you have two choices on how to mix water. One, from the handsome tank-to-tank valve we met above. But for that option (without the mixer tank) to give us the optimum temperature, we need to drain some or even most of the attic tank. To get it from 80F degrees to 100, with the roof water at 120, we would need to drain half the tank (could be as many as 40 gallons), then refill it with the roof water. It's handsome, but, alas, this is not the knock-out such as the mixer tank. If you need a ten-gallon shower only, while others don't need a shower for a few hours yet, you can now mix five gallons from the attic tank with five from the roof. I told you, a stunning knock-out. And others can then get real good at the math to engineer their own perfect temperatures without draining massive amounts of attic / roof waters (on many days).
It may be redundant at times to have two attic tanks, but it comes in very handy. The knock-out tank should be insulated too, and perhaps should be small to retain more heat. It can be used routinely for one shower at a time. One problem is that it complicates the cockpit controls to have three more valves: 1) one to feed roof water to the knock-out; 2) one to feed attic water to the knock-out; 3) one get knock-out waters to the showerhead, or to drain the knock-out. But these three valves can be kept to one side so that everyone knows they are the mixer-tank controls, their favorites. And, yes, another thermometer for this tank too.
As the knock-out is lower than the other tanks, it's got to be fed through one automatic shut-off. Water from the two other tanks are brought through this one valve. I assume that gravity-fed water (i.e. at low pressure) will penetrate the typical shut-off valve.
What if both the main tanks are too hot for a shower? No problem, the little knock-out at your service. Drain one shower's worth of hot water from either tank, and let it cool in the little knock-out. Or, if you're in a hurry to go feed the chickens, branch a cold pipe to another valve (little boss) at the cockpit, to add cold water into the knock-out at your pleasure. Can it get much better?
Yes, it can, if you don't mind a second spout at your kitchen sink, and you can pipe it from the little knock-out tank so that you have the choice of using the water in either main tank before it gets colder. This is a little like fantasia. Why waste those waters too cool for your shower? Run them to the kitchen to wash the dishes, and save the warmer water for showers. And, run a pipe to the laundry room, and pour the semi-warm water into the laundry machine (while it's filling with cold from the regular / household inlet) for a better wash than hard-cold can give.
My top-loader laundry machine shuts the water supply when it senses the target weight of water. I can therefore pour water into the machine with a five-gallon bucket while it fills with cold water through its own hose system, and the machine always shuts its cold water when it fills to the same level (whether I pour the bucket in or not). This can work well with cockpit waters.
After deciding on which tank(s) you want to use for kitchen and laundry, the valve controls for those rooms should be as near as possible to the tanks, and pipes (or hoses) should not be large (1") unless needed. That is, the longer and larger the pipes, the more that warmed waters are wasted in the water left in the pipes after usage at the taps.
Just one more pipe to the dog's drinking bowl, and we're done. We're going to be the envy of the rich.
One thing I didn't mention. The tank-to-tank valve allows water to go either way, to either tank. No water flows if both are at the same level. Water flows only into the tank at the lower level. So, when the attic tank is colder and not very useful, one has the option of running warmed roof waters to mixer tank, and then opening the tank-to-tank valve to get some attic water back into the sun. This tells me that it's maybe not a bad idea to make the mixer tank a large one too, and well insulated, in case we'd like to drain all or most of the roof tank, at say 2pm, in order to run more of the attic water back into the sun for a few hours. In the north, the sun at 2pm is almost still straight overhead hot-hot-hot.
The water in the mixer tank may be shower-good for a few hours after 2 pm, I wouldn't know how long. The problem is that a filled mixer tank won't be at its greatest capability for mixing to the desired temperatures, but the advantage, aside from the very option itself, is a greater volume of shower-good water. The hope is that the attic water run into the sun will absorb more heat than the water run into the mixer tank will lose.
Or, suppose that the roof water is fairly warm, but heavy clouds roll in at 2 pm. The initial purpose of the attic tank is to receive these warmed waters before a non-sunny period cools them on the roof. The cockpit allows, at maximum, only about half the roof water to drain into the attic tank, and if the latter has water in it already, less than half. If you draw all this on paper, you will get it easier. Everything I've said so far have the clues for you to put this into a simple drawing.
When the two tanks are equal in volume and level at their tops and bottoms, the attic tank can take only half the roof-tank waters in one draining. If the attic water is cool, one wouldn't be making a good decision to run the roof waters into it at this time. A large mixing tank can now serve as a back-up attic tank that can, because it's lower, take all of the roof tank's water. Nice and cozy, stay warm until shower time, please. In the meantime, the attic was heated for half the day, and it's heat will continue to heat any water in the attic while the skies pass clouds over the house. That attic water might still be warm enough by dinner.
Whenever there is enough attic-tank water in the morning to drain into the roof tank, by all means do it, because the water in the attic will be warmer than the cold-tap water from the ground. You're giving the roof tank a head start that way. And you're not wasting all that attic water after all. I've got the attic tank set up to make things easier to explain, and to understand on your part. Both tanks have the 80 gallons, and both tanks have the same water level when they are half full. It doesn't need to be this way. If you want to be able to pour more than half a full roof tank into the attic, it can be done with the roof-tank pipe at the very bottom of the tank, and a broad (large square area) attic tank. In this way, when the roof tank is, say, eight inches from empty (water level at eight inches high), the attic tank is only eight inches deep due to being so broad. If the tank is roughly four feet square at eight inches deep, you're in the ballpark of 80 gallons. However, you now cannot get much attic water to an empty roof tank. And, a broad tank loses heat faster.
It works the other way. With a tall attic tank of 80 gallons, you can get a greater depth into the roof tank, about 3/4 full. But you can't get the level in the attic tank higher than in the roof tank. Advantage: if you have two tanks on the roof each at 80 gallons, you can put one higher than the first and drain the upper to fill a tall attic tank. Now you need two boss valves at the cockpit.
I've just realized that the attic tank can be filled to higher than half with the one roof tank alone. This is just another option for your inventive genius to ponder. At noon, drain the roof tank to the attic tank so that both are at their middle levels. Close the tank-to-tank valve and refill the roof tank with cold. You have the option now to drain the roof tank again, at 6-7 pm, in case people need/want showers a few hours later. This time, the attic tank will fill to 3/4 full because it's half full to begin with. Likely, both tanks will have different temperatures that allow some mixing to get the best-possible temperatures.
If there's lots of roof water left after shower time, drain as much as possible to the attic tank to stay warmer overnight, then put it back to the roof in the morning. Here's a great idea with two roof tanks: use the lower one for showers, then pour the upper roof tank to a tall attic tank to stay warmer overnight, then drain the attic tank to the lower roof tank when it's warm / sunny enough outside in the morning. That head-start with chill-killed water can be a significant help on less than full-sun days.
The upper roof tank acts as a chill-kill as compared to using ground water, but it's also a second source for times when you may need more water. There will be cloudy days when the roof water won't climb over 80F, but that's good for pouring to the attic in case it's sunny the next day.
It won't be easy to know the volume in the tanks from day to day. One could get a good idea by the temperature changes when mixing one tank water with another. But, ideally, one needs a pressure gauge at the bottom of each tank, with a wire to a display in the shower stall that gives the depth of water in psi (.43 psi per foot of depth). If the display reads 1 psi, the depth will be known to be about 2.5 feet. Without knowing the depth per tank, the pilot's going to crash and make the crew upset. There's no auto-pilot in this system. The pilot never gets to relax. Every day has different weather. Turbulence ahead. The wife is sleeping with cold back to you tonight because you routed her shower water into the dog bowl, and it flooded the floor, which she had to mop up. Things can get bad with one wrong decision...so we've got to find shallow-depth gauges, like our marriage depends on it.
A Pressurized Tank Can be Drained and Refilled.
There is the option of not using batch heaters on the roof. Instead, use the metal pipe / coil type that require a slow pump to circulate waters. The first question is whether you will have enough solar power to run this pump all day. I'm sure that they can be turned off automatically when the sun don't shine. So long as there is sun, you can have solar power to the slow pump. With the pipe heater, there's no worry about plexiglass breakage. Without being able to drain by gravity force, you always add cold water to the tanks. That's the kicker, the reason I went to the trouble of describing the plexiglass tanks.
However, I have just realized a way to drain a pressurized tank, and to fill it up again safely. Recall the risk as described above with a pressurized roof tank: someone might forget to shut the air-outlet valve while the tank is being refilled, which lets water out continually. Here's the solution, though it's not without some work.
Run a pipe from the air-outlet hole of a pressurized tank to a valve at the cockpit, and finally to an automatic shut-off valve inside a small container for the purpose. It can be very small, not used to hold water, and it has an air hole at the top. Let the container be higher than the pressurized tank. Run a pipe from the bottom of the container to the pressurized tank. Shut the cold pipe to the pressurized tank at the cockpit, and open its air-outlet valve from the cockpit too. Now, drain the hot tank water as much as you like, allowing air in through a one-way valve. As water drains, the container's water falls into the tank too, and this opens the container's automatic shut-off so that air can pass through it. When showers are done, turn on the cold pipe to the pressurized tank, which forces the tank's air into the container and out its air hole. When the pressurized tank is refilled with water, water will begin to enter the container, filling the latter up until its automatic shut-off closes. Perfect. I can't see any problem.
If you want the roof tank to act as a pressure tank, allow some air to remain inside.
Free Energy Has Been With Us a Long Time
Heater tanks on/off the ground have some advantages. Suppose some hot rocks could jump into the tank. Then, imagine them jumping out and bathing in the sun some more, to repeat the process a half hour later. Metal heats up much faster than rock, and looses more heat in water. Imagine some hot pieces of metal sitting in the sun baking, too hot to the touch. Suppose someone arranged old bolts spread out on a flat surface (this is where the cookie expertise of women comes in), then slid them into a basket of some sort made of metal wire (akin to piling dinner rolls in a basket). Then, dip the basket into the water (deep frying French fries comes to mind). The basket itself has been baking in the sun (where oven mitts). Your water just got significantly hotter in a few seconds. There's no law saying you can't have more than one basket full of metal pieces (although Obama's wife wants to limit how many French fries we can have at one sitting). You can even dip the baskets seven times daily and not be arrested. It sounds crazy, but it works: tax-free hot water easier than baking cookies. Can't you just hear the sizzle?
What better thing will you have to do, in the trib, after the headless chicken is hung upside-down to dry? Dinner is nigh, and the workers in the garden will soon need a shower. How about small lengths of copper pipe, like hot dogs neatly lying side-by-side on a flat hot grill in the sun. Get some gloves on, grab as many as you can, dip for a few seconds, and lay them back out again. The only difference between the miracle of hot rocks jumping into your hot water and you placing copper pipes into it is the miracle of your movement. Pick up the next pile, and do it again, looking over your shoulder to check for revenue people. They know how to tax you for using the sun, so careful not to tip them off, or short pieces of copper pipe will have tax built in.
It sounds so corny to be dipping metal into water, but if that's all you have when the sun is going down, when the shower water is still a little cool, you've got to do what you've got to do. Throw your gold jewelry into the sun, use it to conduct heat. It never before saw a better day. The Lord will smile on you. He does not despise the small offering, because most people don't offer anything at all. Dipping pipes for the better comfort of your work horses is a big deal in God's perspective.
Where's a good place to heat water on the ground? Right up against a south wall, not necessarily of the house, where heat accumulates in all the surrounding materials. A tank lying on the ground won't benefit from a relatively cool ground temperature. At cool times of the year, it would be better to elevate the tank off the ground while allowing sun to shine underneath it on yet another metal surface acting as a "heating element." Enclose the space over that metal with a transparent material, and much of the accumulated heat within will get into the tank.
The cool seasons are when people have extra energy for dunking hot metal into a tank. Cool times are when the hot dunked metal is needed to boost what the sun may be unable to accomplish directly. There can be a wall facing south specially built not far outside the house, reserved for showers, and everyone can have their own tank against that wall. One tank snuggled against the other makes sense. At the end of the day, the owners use whatever they manufacture in heat for their own shower; if the owner beside you wants to be lazy that day with their tank, too bad, they can't have your water, at least not for free. You could probably have a one-hour slave for a gallon; imagine what you can get for three.
When building my house, I had a small 4' x 4' shed acting purposely as my shower stall; in the cooler months, "showers" could be arranged at peak afternoon temperatures, appreciated when the air temperature outside is well under 70 degrees. It could be as much as 20 degrees warmer in the shed (but only when sunny). But my showers were with a margarine container over the head, not from a showerhead.
This I know, the containers or buckets that everyone can have, each to his own, they have got to be put "indoors," in the sun, as the cool season comes on. Not in the house, but in a casement outdoors. You've got to make the buckets a greenhouse. There's just no question about it. It's too early for the wood stove, and so you need the greenhouse. Anything that keeps wind off and lets sun shine in.
The benefit to having small tanks off the roof is that one can shift them. We might use a tank on wheels upon a wood patio floor that wraps around the south-west corner of the house. Just wheel it from south side to west side. That setting sun on a west wall is hot hot hot.
Suppose we arranged several flat aluminum sheets about 16 inches square, each piece connected to the other by typical small cupboard-door hinges that you can pick up for a nickel each from Mr. Junk Yard. The aluminum sheets on hinges (like an accordion) can be unfolded into a long string for soaking up the sun. When they're hot, fold them back up, and dunk them. Thanks to the slight thickness of the hinges, a small space between each sheet allows water in to suck the heat out much faster. It's a miracle. There's no use asking God for free energy because you have it already. You can be the perpetual-motion machine, for a couple of hours, anyway, on every sunny day.
We could hang the hinged aluminum sheets as our "curtain" on a sunny, inside window of the house. It'll get hotter there than out in the breeze. We could maybe convince the ladies to sew us up some deluxe pail warmers in return for making them the aluminum curtains. There's some good bartering to be had here. Opportunity knocks.
With the cheap glass / windows we can purchase from Mr. Junk, we could turn the outdoor communal shower into a sunroom. Build a fireplace in there to warm water in winter that also warms up the shower room, who could ask for more? Can you imagine how hot it would be if you were a little piece of water in a copper pipe passed through the flames of a fire? I thought about that idea all by myself. Water in a pipe in a fire. Magnificent. God even made the hot water rise all its lonesome in a pipe, pulling cold water behind it through the fire, it's praiseworthy, bow down and worship.