Off-Grid Shower Heated by Compost
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- Опубліковано 26 сер 2021
- Compost piles often heat up, and given the right conditions they can get really hot. But can that heat be used for anything?
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Replacing the hose inside the compost with an aluminum coil pipe would drastically increase the thermal conductivity, allowing you to extract the heat from the compost pile faster (back-to-back showers). If you really wanted ensure there is warm water during peek usage you could store the hot water in a thermally insulated container (like an old water heater). Very interesting topic! In Jamaica we use solar water heaters which gets the water so hot it will scald you if you're not careful.
Yeah, an aluminium pipe would definitely help with heat transfer. I was thinking of just inserting a container right inside the core of the compost to provide more warm water, but an insulated tank outside would also work. I can imagine the sun in Jamaica would do the job well!
@@REDGardens it's worth measuring the heat capacity and resistance of the compost.
I think the likely limit is how quickly heat transfers through the compost, rather than how quickly it transfers into the plastic/water.
A better conductor might get you a few seconds longer on the shower though? To cool off the compost that is touching the pipe
@@REDGardens legionella
Also, insulating the exposed pipes on both sides of the pile with pipe wraps/pipe duvets.
Compost is known to be used to heat greenhouses too in winter. I am really wondering if you are willing to try in your polytunnel to keep the overwintering plants warmer during the winter.
It is definitely an option!
The issue there being gases, which you have to closely monitor (and pick milder times, air out, then enter) when you have to actually go in there.
@@aenorist2431 definitely true. But a perfectly ventilated compost pile should produce only a tiny quantity of methane and mostly CO2, given the proper amount of air. Of course a little gas exchange with the outside is desirable, but in most commercial greenhouses actually they use methane burners to add CO2 for plants to use, and if you do not overdo it, it could be a feasible option. :)
@@manuelsza7064 the problem would be ammonia off gassing particularly if fresh animal manures are used. there is a danger that ammonia build up will scorch the leaves of winter crops and potentially kill plants.
@@teatimetraveller you are right once more. The trick is having a lot of nitrifying bacteria (as Nitrosomonas and Nitrobacter) active and manure (dry enough) mixed with a proper amount of starches and low nitrogen plant matter in excess of oxigen. It is easier said that done, though. We are getting a bit too technical, maybe. :)
Put a small storage tank in the pile, like an old electric water heater copper tank with no insulation, then you need almost no pipe, bounce back will be slower due to less surface area, but you might get 75-100 litres of stored hot water. Also a higher efficiency head will make the hot water go a lot further.
Finally a shower waste heat recovery coil would add maybe 15% extra hot water capacity.
So as proof of concept this is amazing, a bit of refinement and it could really go places. Very well done.
This is exactly what I thought when I saw this video, because essentially what we thought is a bit like how a hot tub heats, initially taking a while but then the heat once built up stays hot with this constant warmth..that would be way more effective.
Before me and my, now, husband built our house we had to boil water on a hot plate and use a cup to pour warm water over ourselves. This would have been so useful. In my county of Mississippi in America we do not have permits on housing. Countless people have no heat or running water. I’m sharing this. If even to keep livestock water unfrozen. This is awesome.
I think it can have a lot of household uses!
My son and I did this for a homeschool science fair project. He took a shower outside, in below freezing temps, here in Montana. He loved it
Awesome!!
Keep the good work. I saw all your videos . Some times I see video many times . I like you scientific method 👍. Thx
Interesting. VERY interesting.
Here's an idea...
Use the loops to a hight of say three feet. Then have the flow (or direction) "drop" into a (say) five gallon absolutely sealed vessel located directly in the center and have the flow raise again to the shower head, all under pressure!
The initial heat build up will be constant from the overnight heating, with half the main vessel exchanging warm or hot water for the cooler new water from the mains. It won't go cold, untill the entire five gallon tank is emptied, which will never happen over an hour. The tank will always allow warm water to hit the shower head, with the cold direct water mix being reduced as time progresses....I think 😎
Thank you for you brilliant idea, or at least, if not your idea, then thanks for experimenting for us.
👍
I was thinking larger diameter tubes in the pile. But I like your solution better.
Thanks! Having a sealed container in side the compost would definitely buffer out the usage.
@@ecospider5 I kind of like the simplicity of a larger diameter tube. I went with the smaller one because I thought it would increase heat transfer, for on the fly heating, but now I realise it is mainly about slow heating and storage, so a larger diameter pipe would work, but it might be harder to bend into the tighter radius.
@@REDGardens Actually, if you get it full of hot water when you first buy it in a coil, it becomes maluable and you can "tighten" it's curve.
Cheers.
this is amazing! I never thought i'd be this interested in compost but here we are. Also, congrats on getting to the front page of Hacker News!
Thanks for the video, I love this idea.
There is a UA-camr that heated his greenhouse with compost heat through the winter.
Great videos as always! I always look forward to your next one.
This is so innovative. The one compose pile can also be connected to few other compose piles. The heat can be control using cold and hot water as normal usage does. The pipes can be regulated so that the water can be alternated flow to other piles. Also it's easier to maintain those compose pile that need to mantain. I really like this idea. Tq
Thanks. There is so much to play with and explore with all this, and I do like the idea of using the water to help manage a system.
Nice experiment ! Definitely made an impression!
Great idea 👍 I have a solar shower ☀️🚿 in our garden. We have to wait quite a while to take a shower in the morning. So this would be a good possibility to take a shower early in the morning. 🚿🤗👍
Well done! Scientist at work! Much appreciate!
Thank you!
Your channel should be renamed 👑The Compost King👑super cool project!
Haha, thanks!
Great idea with the compost shower. The video done by Geoff Lawton seems to work great. 150m of pipe in a bigger compost pile with a 5 min shower on a 5 min recovery for next shower. Hopefully you will do a version 2 as I wonder how it will perform over here. Great stuff m8
🙂 I tried it again this year, with even more pipe, and hound it had a really good shower length.
The most obvious upgrades to this are an insulated water tank, and more conductive tubing.
Easy of turning/replacing the compost wise, I'd maybe try a doughnut shaped tank? Have the compost in the middle as a stack, then a layer of water around it which makes up the tank, then a layer of insulation around that.
You fill up the tank, then let it heat up. As water is pulled out, you let more into the tank to heat up. The input could still go through the compost to only add prewarmed water, but I don't imagine if make too much of a difference
Insightful as always. I’ve been interested in compost heating for hot water/energy for a while, most of the systems seem to be significantly larger than one cubic meter, but it’s interesting to see how effective even a small pile can be.
I was surprised how much a small pile like this was able to do, and I do wonder how much heat could be extracted.
Great project. Very well presented with plenty of detail. Thank-you
This was a very interesting and fun video. I love how creative it is. I'm interested to see what else you do along these lines.
Thanks!
I love Red gardens
:)
We usually fill it up in a bucket B4 shower so the overall water would mix on its own to have warm water. The water tank we have is exposed to sun. 🤩👍👍👍👍👍👍👍👍
Sounds like a good option.
I did a similar thing once to heat my propagation greenhouse. I built a compost heap about the same volume of the greenhouse below the benching. The compost heap was constructed with chicken wire and fence posts, filled with manure and wood chips and covered with an old carpet to keep the heat in. The flexible tubing was coiled round the heap while filling it, going through the middle of the heap in a zig-zag pattern and the top pipe was fed through into the greenhouse benching, again with a zigzag pattern around the benches covered by sand. As the water heated up in the heap it rose to the level of the benching and as it cooled circulated back into the heap to heat up again in a gravity fed system. It kept the greenhouse benching warm enough for propagation all through the late winter and early spring.
Amazing! I really appreciate your videos! Keep it up!
Thanks!
Diego Footer has a bioreactor concept with a center hole of the wire to give active air into the system. Love the idea of using water flow to adapt temp to extend or influence decomposition! So cool....
I have seen Diego's setup, which is very interesting. I think one of the purposes of the holes is to get rid of some of the heat, reduce the temperature to allow a more biodiverse ecosystem. Which is apparently great for the compost but not so great for using it as a heat source.
@@REDGardens Yep might be right. Im thinking about the bioreactor... the idea was ot have adequate airflow for the worms who want to be within a certain distance of the surface. If there were vertical air flow tubes that you pull out after the initial heat build up, you could in essence use that to route heat through until that stage of the process is done, then pull them out and have airflow for the worms and inoculant process of compost to thrive aerobically. You could then connect several piles and heat water progressively from older piles that have begin to cool through piles that are heating up. Then disconnect them when they are dont and use then in a new pile and add to the manifold.
Love what you do and how you are doing it. Ive played with biochar, and using the heat to drive ovens/stoves and even thought about how to roast coffee. Things work at some scales and then fail at others, but experimenting is fun and valuable
Somewhere down stack you mention thinking about putting a container into the over-all pile and I think that's a very interesting idea...but it would be a double edged sword. The benefit of the pipe is that it transfers heat very quickly. If you had, say, a 20-30 gallon water storage tank in the middle, it would get hot, and stay hot, and provide hot water for a considerable period of time.
But it would completely tank that 10-15 minute re-fresh, as it's flooded with cold water at the end of the last shower. Instead of one short shower every ten minutes you'd get one longer shower every couple of hours.
So better for, say, personal domestic use but possibly not optimal for the situation at hand in this case.
Hats off, effective research & execution, always interesting to watch!
Fascinating as always Bruce, thanks.
Excellent experiment
I love this experiment and breakdown of the results! That sounds like a very successful first trial run for sure.
Good experiment, you've gotten a lot of great feedback to improve this water heater. Another use for compost heat I've ran across is using compost heat and a Stirling engine to generate electricity.
this is a great idea. Appropriate use of technology! Love it!
Glad you like it!
Very interesting video, as always when the video ends i've learnt something new
I need to try something similar this late winter for heating up a small greenhouse
Loved this!
Really cool experiment and we'll documented as well. Cheers!
Very cool idea, thank you for sharing.
Wow, i totally missed this one and now mu poly-tunnel wont have a compost heat-generator this spring.
But i might be able to squeeze out some tomatoes in Quebec just before christmas thanks to this idea.
Interesting stuff, glad you found the video!
Interesting and amazing! Thanks for sharing.
Very qualitative video
we use manure based hot beds in our propagation tunnel to provide bottom heat to our early module trays. we produced around 20,000+ this spring including mediterranean crops. We then cover the hotbeds in a thin layer of compost and grow chillies on them. Then use the material the following year in our tunnels. It works well but lots of moving of heavy stuff not so efficient.
Run the pipe into another compost tube so you could make one and let the hot water go into the colder pile to keep it worm. Or would it be better to run it into the new pile 🤔 so it preheats it then heats up more in the second.
Cool ad hoc idea and 1st implementation !
Thanks!
What if you build two such heaps to use either alternately allowing the water in the first heap to reheat the water or just keep them inline thus doubling the hot water produced. It would take more plumbing, but how about starting one heap when it starts to cool start a second heap feed the water from the first heap (prewarmed) into the second to boost it's heat, when the fist heap has more or less cooled off break down heap and rebuild with fresh material and reverse the water flow. Hope that makes sense, and gives you something to think about ,always find your videos interesting.
Nice experiment
I really enjoyed it.
Take a container of water and put it in the middle of a pile of compost and add grass every few days and then there was an amount of water and try to take a shower. It's best for the pile to be in the ground
FASCINATING
Thank you.
Wow that's brilliant
Thanks!
I have always wanted to do this.
So did I, and am really glad I did.
@@REDGardensI would like to use it to warm my henhouse in the winter.
Maybe the coils could be used to regulate the optimum composting temperature with some sort of thermostat and water pump.
That would be really cool to explore.
I wondered the same myself.
Дякую за інформативне відео!
радий, що тобі подобається
i think this idea was pioneered by Jean Pain in the 70's
he used it for household heating, but he used a huge compost cyclinder
Ah, yes. I remember reading about his explorations.
We have a car radiator for use in a pinch to make a cool spot for the cat in the summer. If you have a lot of extra water hose, just set it up in the sun and all the water in the hose will be very toasty. A split water feed from the tap can then be rejoined for a very consistent heat output for the duration of the entire supply in the solar hot water hose. Or just use a hot black plastic base to stand on in the shower, and you can comfortably take a cold shower if your feet are standing in hot water~
Wonderful. I wonder if a five gallon mixing tank between the pile and shower would even the temp out. Shame to let the initial blast go to waste. Maybe a perforated stand pipe in the center of the pile for oxy. Double coil for outside and inside. But more fittings, complexity, and cost. Gotta wonder how to rig a more permanent "boiler" type rig. A garden shower. Or greenhouse heater of course. Have to keep it simple for a temporary setup.
Fantastic experiment, I wonder if the result would be better if the hot water was extracted from the bottom of the pile rather than the top, as heat rises the incoming water would hit the hottest part of the pile first.
I have seen a similar system where the compost pile is wider and taller and insulated all around with bails of hay. The hose was longer since there was more room for it .
Bakes of straw or hay would definitely help.
Make a second wire cage to put inside the main cage and cable tie the hose to the inside cage, as the middle decomposes add more material to the middle. 👍
That is an interesting idea, thanks.
@@REDGardens I love problem solving too! You could coil so much more hose into the middle cage before filling attaching to the cage prior. It might not be perfect but may work better? 👍
Nice way of using waste to full potential, am looking to use the methane to run a gas cooker. Saw it on a video and couldn't help but think of the amount of money us gardeners can save just through our compost heaps
Love what your trying to do here.
I've been working with bathrooms showers plumbing and underfloor heating for years. Recently I've put a system in my campervan that uses hot water from my engine to heat my hot water for washing and a shower. It on average takes 10l iters of water to shower with my got water tank is 22ltrs yet the temperature of the water is 70 degrees and a good shower is 38 degrees so we use less hot water and more cold water that's theoretically mixed. So in essence having a lot of heated water gives more showers. Yet the speed of heat transfer from your compost to your water goes through a plastic pipe . Which is an insulator
You might want to use a stainless steel or copper coil more to the center of the compost and most definitely insulate the outside.. obviously with an air inlet. The insulation on the outside can 10 inches from the compost allowing cold air to enter warm up within the insulation and then enter the compost without letting the compost cool down .
It's not a bad idea to insulate the floor either under the compost. As most of the cold comes from the ground.
.just some thought be interested to hear your thoughts
Thanks for this suggestions. I think one of the key issues with this kind of setup is to balance the benefits of insulation, with the need to supply enough air to the mix. In this case I wasn't;t trying got be very efficient with the heat, as there seemed to be more than enough of the use it was getting.
I remember seeing a video years ago where someone had a large compost pile, with insulated pipes running into the house and attached to the central heating - if I remember correctly, it kept their home warm for a couple of months over winter.
I think I saw the same video, or at least similar concept. It is an amazing option to explore, especially as there is a significant store of heat within the heap whenever you need it.
What about using something like an old radiator to increase storage capacity? The higher thermal conductivity of steel would extract more heat after the stored volume is used up.
Rack them up in the pile?
That would be an interesting option. Those radiators hold a fair amount of water and are designed to be conductive of heat, only in this case the direction of heat transfer is reversed.
I am considering heat for a small greenhouse using a compost pile, I need a bit more research but think this will be the year it happens.
I think it would definitely be beneficial to incorporate a water storage container so that it can keep the water when not in use, AND when the compost is turned, assuming you do, they will still have hot water in the meantime. Also you could measure the temperature of the water that's stored so you could fine tune a mix of water so you don't have that phase where the water is scalding hot.
I've seen similar stuff for heating greenhouses, though those either put the pile in the green house, or used large diameter pipes for air exchanges. I think my first pass at improving the shower system would be to increase the diameter of the compost pile by about 1 foot and the height by maybe 2 feet, and then double the length of pipe. Maybe triple. You can probably put two loops at each layer of the pile, one more on the inside, one more on the outside. More pipe means larger volume of stored hot water, and more distance/time for cold water entering the system to pick up heat before getting to the shower. If the line were long enough, and the pile hot enough, it might provide enough heat for non-stop showers. Interesting video as always.
Thanks. I think you are right about the increases in size and length of pipe, for all the reasons you mention. It would be interesting if this could provide non-stop showers. I think it would need some form of aeration though, as the oxygen would run out fairly quick at that volume.
@@REDGardens Maybe like a Johnson-Su Bioreactor. They use pipes to make holes in the center for better air flow.
youre probably better of buying a metal container like a oil drum and cover it in compost. it would hold enough water to keep steady warm water of the core temp. You also dont need to worry of removing the water pipe just insulate the bottom layer and youre done.
I would actually use an aluminum drum or steal drum..... bury that into the pile and make the pile larger. The key to remember here is you hit max temp in the pipe at points and after that it's wasted heat... a drum could store more and while mixing with cold water would give warm/hot water longer.
maybe something to try in my opinion.
try a thermostatic mixer shower, it will let you make better use of the initial hotter water
That would definitely help.
Hello from Chile. I loved your experiment. I think that even though the compost pile doesn't produce too much heat, the awesome thing is that it produces the that heat 24
/7... Quite like a ramp pump pumps little amounts of water but all the time.
I would certainly put one or two 200 gallon tanks to hold the hot water that should be circulating through the compost pile 24/7.
This would help you lower the temperature of the compost to the desired 40 degrees.
If the water and the compost reach 70 degrees then add another tank.
I really wonder how much water you could actually heat up with that size pile.
A recirculating system could probably keep a hot water tank fairly well. Once your build is in place, the difficulty becomes managing the pile.
Replying to myself but I bet the total heat energy produced could be estimated: we know the volume and there’s already two temperatures being captured over several days
What I meant is that with a water tank you can take a much longer shower and it can also help you make a better compost pile
I’m curious to know the rate of progression of the compost. If this method is regularly removing heat from the compost, could that slow the process? I wonder if there’s a chance it could slow the process and improve the quality? That variation definitely allows for some less resilient microbes/life forms to thrive deeper in the compost periodically. Who knows what effect that would have?! Another fascinating video with a lot for the mind to chew on. Thank you, wish you and your family the best 🙏
Thank you! I think those are really interesting questions. I suspect that removing some of the heat could actually increase the rate of decomposition, or at least the diversity of microbes as you suggest. I was thinking that insulating the pile and not removing the heat for the first few days would take care of weed seeds and disease organisms, and then removing heat to drop the temperature to a more biologically diverse range, and possibly adding microbes with a watering of compost tea might help with the quality.
Very interesting! I wonder if you could do a system where you use (spoiled) stray or hay bales to create a relatively insulating and larger surround, then fill that with compostable materials. Would a perforated pipe or multiple pipes sunk into such a pile create enough aeration? I'm intrigued by your notion that a larger pile might allow for a much longer length of tubing to be heated at once.
It worked 👍 would you consider adding a better ratio of brown in the mix it looked a bit green to me maybe adding layers of wood chip/shavings and see what results you get? Edit: I wrote this before watching your summary.
Yes, that would help make it last a lot longer, though I wanted to see what would happen if I used just the material that was gathered clearing the space for the camping area, and was pleased how it worked.
I'd love to see this idea combined with thermal mass to provide a long-lasting heat source.
That would be interesting.
Cool...
:)
I wonder if you could actually combine air source heat pumps with compost piles.... Have your compost area covered with a roof that slopes up towards where your air source heat pump is located so it can extract at a much more efficient rate without needing to disturb/pipe the compost pile. There must be a lot of heat leaking off a pile over the course of a season and I'm sure you could stockpile enough material to keep it reasonably warm over a winter period?
I have never heard of this water heating method before, and that is clever. How does one find that extra long thermometer that you use?
Nevermind, I searched "compost thermometer" and figured it out.
Those thermometers are great, I recently bought another one, not that I am much more interested in the heat produced by all the compost piles I make.
i wonder if its have a better way and countinous with less work just adding material
Hello I border Tipperary. I am so happy to find your channel. I've been making my eco house off grid, just stuck and confused about solar and wind power. I paid 6k for a solar system but they just fitted 2 indoor electrical plugs outside & 11 solar panels, needless to say I am trying to get that resolved while looking for a system, any recommendations would be greatly appreciated ⭐
If you feed your pipe to a tank, you could take advantage of passive thermo-siphoning (en.wikipedia.org/wiki/Thermosiphon). This would have two advantages: i) provide a hot water reservoir for multiple showers and ii) potentially keeping your pile closer to the optimum temperature by sequestering heat more steadily.
^ this comment deserves a cold beer! Nice idea.
Just be careful of the risk of legionella developing if the shower facility isn't run frequently. The water in the pipes is effectively stored, stagnant hot water at pretty much exactly the optimum temperature for legionella bacteria to multiply and become dangerous. If the pipes are flushed frequently (by using the shower) then this wouldn't give the legionella long enough to become dangerous but if left unused for even just a few days, the next person to use the shower could be potentially put at risk!
2:40 make it? solar panels? do they do the work? maybe with some way of battery?
i dont remember how the system is calls. that system reuse heat from houese i wonder if its possible to have a little roomy-house by side of house to use that heat to heat up the house
Wonder if you could do a kind of inverted water heater this way? A barrel in the core with the compost material in a ring around it.
That would be interesting to try. One key issue I think would be to be able to set up the material to last long enough, and to change easily enough to maintain a consistent supply.
Thermal transfer, gathers that heat, but also takes it away - ie: cools the compost. Is this not detrimental to the thermophillic bacteria ? I am asking out of curiosity, because I truly always wondered about that. I know you mentioned it as well, Bruce, but I like to think it doesn't affect things too much. A lot of heat also impacts the process negatively.
I think it is a good thing for the bacteria, and the decomposition process in general, to remove some of the heat, or at least to prevent it from building up to a temperature that causes them to slow down their activity. This is one of the key learnings that I made while working on this little side project.
Adding thermal mass, maybe by setting the compost pile underground some amount, would probably be better for intermittent water usage like showers.
That would be interesting.
I'd go with copper pipes pre coiled around a steel tube myself to get a better heat transfer. Maybe have some kind of hinge and lever set up to pull them out of the semi finished compost. I'd also feed them into a tank so you get passive heat. You'd have a lot more temperature control that way and you also wouldn't need to have drinking quality water in your system. You could add to the water in the system so that you wouldn't need to worry about the pipes freezing in the winter. Also with a tank you could add a pump to get better pressure. If you can't be bothered with all that then I'd just use your current set up to heat your poly tunnel in the winter
More heat transfer isn't always better if the pile is hotter than you want. You don't want to draw too much heat away after all.
steel pipe and copper tube is an interesting idea, especially if it could just be pulled out.
Do you think the compost pile could tenderize food like okra and green beans
is exist machine that blends material to compost?
👍👍👍👍
Salu2
:)
Leylandii hedge chipped gets really hot (wood chip) in compost
I'd assume building one or two of these in your poly tunnel towards the end of the season could be a good way to keep the temperature up for a slightly longer season.
It would probably help, I wonder how I would redesign I to maximise heat transfer to the air, but only when needed (such as at night.)
@@REDGardens How about moving air with a vent through perforated drain pipes buried under the compost pile. It would pull fresh air down through the pile, allowing it to heat up, and then moving it into the polytunnel. This would help aerate the pile as well
How is the compost shower going now?
It was only in place for the 2 week event. Then the whole thing was dismantled.
4 celinders and maybe somehow to store that?
Can you get the Campers to Pee on the heap, to increase Nitrogen and thus heat for the shower? !!
That would work if the material was higher in carbon, but I think there was already enough nitrogen in this batch.
Write a book!
Thinking about it.
Tu byłem. Tony Halik 2021
I tested a more compact compost reactor which is made from Polystyrene.
Its size is only 0.28 cubic meter(a little smaller than a washing machine) but it got above 60 degrees Celsius with no problems.
Due to its size, it requires less turning and is possible to be transported.
I think adding some heat insulation to your build will make it more compact and effective.
Here's the footage and records: ua-cam.com/video/hWEspeI20ZU/v-deo.html
What if you put a tank in there instead of just a hose
Another option.
Doesn't taking this heat from the compost slow it down?
Probably, when the material had cooled quite a bit, but initially I suspect that removing some of the excess heat helped to speed things up.
@@REDGardens yeah there will be an element of maintaining an optimum temperature or enzymes will denature. Did you use a thermostat to turn the flow of water on and off?
If that wire gets expensive, then the wire within a piece of Harris fencing will do the job - should be able to get it for free as there's usually a pile of broken fencing around most building sites. You not using any woodchip? I think if you keep it below 50% moisture you won't be producing any methane. I'm guessing you've heard about Jean Pain. You might like this ua-cam.com/video/8X6Jzqv-ymQ/v-deo.html. And you might find some technical detail here too ua-cam.com/video/BPaCMR4vZlM/v-deo.html
Hi, great idea. I think next time you could think about a thermostatic shower valve, making the hot water flow rate self-adjusting when mixing water - it's fully mechanical without the need for electricity.
copper pipe