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Forum Index : Solar : Deciding if I should build this solar heater
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| rogerdw Guru  Joined: 22/10/2019 Location: AustraliaPosts: 795 |
Yes, thanks for that. I first read about it 25 years ago ... and then didn't hear much about it until recently again. And I've searched and read all sorts of info but so much of it is generalised and not too much specific. I kinda understand the principle and that you have to choose an appropriate melting point PCM ... but it's the actual nuts and bolts and quantities and approximate costs that I'd like to understand better ... and some comparitive examples with alternative methods. I think that's why I kept going back to PCM because we don't have any internal brick walls to soak up any excess heat I might be able to pump into the house during the day. Certainly we have a huge area of cold tiled floor, but again how do you get the heat into that when the slab is working flat out against you. Yeah I know, I'm getting a bit ahead of myself. Just trying to plan ahead to work out what I'm going to do with all this heat I'm going to generate ... I hope.  You are quite likely correct. Maybe that's why it disappeared off the map for 25 years and is now being revived again for the next lot of suckers. If you have a few minutes, there's a case study of some of this gear being used for cooling over in WA. It's fairly detailed and looked reasonably credible to me ... but I'm no scientist. I'd love your views on it. If you go to this page and then click on the read more under the "Energy Carrot" story ... https://pcpaustralia.com.au/news/ Cheers, Roger |
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| rogerdw Guru Joined: 22/10/2019 Location: AustraliaPosts: 795 |
Mmm, ok. I can certainly see the fan heater helping. Better than the nothing that we are using at the moment. I'm going to have to stoke up the fire soon, can't put it off much longer. I need to do some research to find them. Yeah, it's looking that way. Marketing people always work out a way to put one over gullible people (like me) who haven't done their homework or understood a process yet. Yes, and then it depends on where the material is going to be placed ... under a floor where you need several degrees higher to overcome the losses the slab is going to soak up before it gets to you in the living room above ... or in a box in the corner like I was talking about. Yes, thanks. I think it was mainly because I was excited about it so long ago when I first heard about it and hoped to one day be able to make use of it. But the lack of understanding has been my hurdle. I just didn't want to carry on with this project and not use it this was going to be an ideal time for it. I think I was avoiding the water heating idea with the evac tubes because I am such a cheapskate ... I just didn't want to have to cough up for all the heatpipes I would need ... or go to the trouble of making them. If they'd have come with heatpipes, it would have been hot water all the way. The easiest for me at this stage is still going to be hot air. So initially I still want to just blow it into the house like you are doing with your fan idea. I've been taking temperatures all over the place so I can have a before and after so I know if it's worth pursuing ... and it's one of the reasons I haven't started the fire yet because hopefully I can see a benefit from the heated air before I stoke it up and then I won't be sure which one is doing what. Yep, that is exactly right. I reckon I can build a full set of 18 tubes over the weekend from what I already know and can start piping in any heat to see what it does. The tools and meters I've ordered off eBay should be here early next week too ... so I should have some actual figures to work with as well. Oh you know it well ... I'm surprised you haven't seen the thread over there already. Cheers, Roger |
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| Davo99 Guru Joined: 03/06/2019 Location: AustraliaPosts: 1577 |
You know I totally get that! When I was a kid, I saw a segment on a show Called Landline ( which is still running but pathetically greenwashed now) on farmers running their Tractors on Veg oil. It fascinated me and I NEVER forgot that and one of them was Running his Mercedes on it. Every time I saw one of those Mercs in the street, I remembered that piece I saw. Fast Forward about 25 years and I read of a group of people doing it. Made contact and Found a guy quite close to me using oil and making Bio whom I am still good mates with and next thing, I had one of those Mercs and was running it on veg oil and have been running engines on it ever since. Some things get in your head and you never forget them. Just use a heat exchanger to put the energy from the air into the water and take it back out again. All you would really need is a pump Pishing the water at the top down through the HE to the bottom of the tank and Blow the air though the air to liquid ( Radiator) HE. Yeah, and going right back, even with the full set of tubes, I'm wondering in winter, how much power you will get out the tubes and how much capacity will be left and if it's worth storing? That said, even the 1 Kw I'm using seems to be having an effect. The caveat there is I can run it a lot more hours than will be available from a solar setup. If you can generate 2 Kw which is more than I can see happening in my ignorance of tubes, Then that effectively doubles the generation hours at 1 Kw. Yep, must test one system at a time. I have been looking for an Old combustion fire place for years to use as a test bed to convert it to an Oil burning system. Seen lots on the net and I can't see it being a problem but need to satisfy myself of any problems and Safety issues. To have an oil fired setup with no wood to worry about would be a dream come true! Still get the wonderful appearance and warmth without the work. Ah yes, Now I get it. I got suspended over there for not towing the line on the green religion which apparently upset too many of the Inner city types and my constant abuse of the " No DIY" Rules. Seems even talking about a general theory to doing something yourself rather than getting in a Tradie to install a retail product is too risky for manicured fingernails and the waxed eyebrows of many of them there. I told them to shove their bedwetting forum full of useless sooks in that Moist dark place which for the majority of the latte sipping so called males there that have their Brassiere in a twist, is in the front as well as the back if you follow my drift. I get it that not everyone is a shed Dwelling nutter like me but I can't stand the insistence that everyone has to be scared little useless whining pussies like them. |
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| Warpspeed Guru Joined: 09/08/2007 Location: AustraliaPosts: 4406 |
Further thoughts on PCM. The energy storage capacity might be relatively high, but it only works at one temperature. In other words the air temperature needs to be significantly higher to get heat to flow into the stuff in the first place. And it needs to fall a lot lower for heat to move back out into the surrounding air. If its buried in a ceiling or a wall there still have to be significant heat swings for it to work, and it only works really well either side of one fixed temperature. Brick, concrete, water, or any of the ordinary primitive bulk stuff will absorb and release heat at any temperature, so outside the "magic" temperature zone of PCM it might actually work better. The most effective non combustion heating systems I am aware of at the moment are still heat pumps. They are continually improving in efficiency, and something like that coupled up to a fork lift battery, with an alternative to solar means of recharging the battery should be able to provide acceptable performance through mid winter. It would also cool in summer, and at night, especially in the months when solar becomes virtually unlimited. Edited 2021-05-07 08:20 by Warpspeed Cheers, Tony. |
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| rogerdw Guru Joined: 22/10/2019 Location: AustraliaPosts: 795 |
Yeah, funny how some things just jump out at us and then hang on. How efficient are heat exchangers percentage wise? Then I have to do it twice ... and I'm scared of water leaks. Apparently this place got flooded because of a burst pipe before we bought it ... that's why it had all new floor coverings when we came in. Yes, that is a good question. Only finishing the testing will answer that. Lucky I'm the eternal optomist or I would have given up ages ago. Yes, that is encouraging, though like you say you can run it a lot more hours than I will likely be able to. I've looked at lots of videos over the years with the same idea .. as well as rocket stoves, pellet fires and wheat burning heaters. My brother's a farmer and we're in a wheat growing area so plenty of fuel available. Oh dear, that's a shame. That's the only reason I go over there to watch you stir them up and show them up for their hypocrisy ... and for being little girls. Cheers, Roger |
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| rogerdw Guru Joined: 22/10/2019 Location: AustraliaPosts: 795 |
Okay, the voice of reason. I have to admit being in the ceiling woried me ... as well as the fact that if it was set up for cooling, it would be detrimental in winter ... and vice versa. Well hopefully I'll soon find out. Mmm .. don't know much about them other than the general idea. I can see the merits in your suggestion. Maybe once I've tackled this air warming system and either got a result or given up on it, then I can get back onto the Warpinverter and can look at all sorts of other ideas. Anyway, I'll put together this full set of tubes and see what it does ... and stop looking at pcm for a while. Cheers, Roger |
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| Davo99 Guru Joined: 03/06/2019 Location: AustraliaPosts: 1577 |
Far as I can see they would be near as Dammit 100%. You can easily oversize the HE ( Car radiator) so the exit water temp is ambient. I had my CS Lister Thermosyphoning into a Subaru Radiator. It's only 6 HP but that's still 4 Kw of heat and even running one stock fan through a tail light globe as a resistor took out most of the heat. I didn't wan ambient temp air going back in so I had to block the front side with cardboard so it wasn't over cooled. My idea with what I'm going to do is enclose the radiator so all the plumbing is outside where if it leaks doesn't matter and then just duct the warm air inside. I am scared of leaks with a DIY setup as well so I'll keep all the danger where it isn't any more. Not much can go wrong or cause damage with hot air. For your setup, I would be running the hot air in through the radiator and then out into the house. If you wanted full heat to the house, Turn off the circ pump on the tank so the water heats up and the great majority of the heat goes to the house. Depending how you set it up, there will still be some thermosyphoning into the tank but if you don't want that, just put a valve somewhere so the water can't flow. When you wanted heat at Night, you run the system the exact same way only turn on the pump and blow air through the rad once again and the water in the tank will heat the air to whatever temp the water is and thats it. The pumps all seem to come with a 3 speed switch. You could have different heat setting and also have the water slowed so some was being heated and the rest exhausted into the house. The other benefit I see to this I intend to use is Cooling. Where I am -generally- night time temps drop a LOT. It can be 30+ though the day and Low 20's or less at night. That's pretty common and a redeeming feature of the location. Really hot nights are rare. I can run the system in the early hours of the morning and cool the tank(s)to around 23 Or whatever and then have that in reserve to run when it hits 30 Odd in the afternoon. My thought is with a bit of a water mist to provide some evaporative cooling, I might be able to get the water down to 17 or so. Certainly cooler than ambient. All you would need do for the reverse process is Disconnect the tubes so you weren't pulling in hot air through the day. It will be interesting to see. Are Wheat burning stoves available here? I have seen some Pellet stoves and the Pellet fuel advertised but I'd suggest as a somewhat educated Guess, even resistance heating would be cheaper. I agree with Tony, for non alternative heating, AC is the winner far and away and you have the versatility of Cooling as well. I never set out to purposely stir anyone, maybe have a bit of fun with their flawed ideas now and then but simply pointing out logic and verifiable facts that went against their virtue signalling fantasies put them into a flat spin. It really is alarming how the truth has become unacceptable when it does not fit the ideal these days. There was certainly plenty of hypocrisy, the only correct way to think changed depending on what the narrative was on the day. I don't know how people keep up but it seems to be very much based on going with the sheeple mentality on the day. Whatever it is, no matter how Ridiculous, flawed or Turncoat, just agree and don't whatever you do question anything. For Universal acceptance and approval, always blame " The Government for not doing enough" Even though all you have done is whinge and whine and not even done any basic research beyond the spin doctored media story they are all inevitably working off as infallible fact. I don't know how anyone can be or think like that. Gives me anxiety just thinking about how dangerous such people are to society and the "Future of our Children" they harp about so much. I hope to hell that Kids like yours are the ones that rise to the top and not the ones raised by the perpetually offended Soy latte sippers whom raise their kids to be boys one day and girls the next.... Or am I behind the times again and they are all supposed to be Gender neutral now? Agggghhh! I'm getting a headache thinking about it. Time to go out and burn some more oil! |
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| Warpspeed Guru Joined: 09/08/2007 Location: AustraliaPosts: 4406 |
You could hang a water/air heat exchanger onto a wall or a window like a window airconditioner. Those drip condensate anyway without any problems. In fact you might be able to repurpose a dead airconditioner fairly easily. Edited 2021-05-07 12:33 by Warpspeed Cheers, Tony. |
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InPhase Senior Member  Joined: 15/12/2020 Location: United StatesPosts: 178 |
This all came about because tough men carved out a world that was too safe. It's so safe that people have to invent a problem just to have one. If you had to worry about a bear eating you every time you took a piss, you wouldn't have time to argue about which bathroom to use. The same with racism. In the US, there is so little racism, they have to make it up. A man on a game show held up three fingers to signify his previous wins and the internet warriors lost their minds. Said it was a white supremacist hand gesture. If there was a real problem in this country, there would be better examples of racism. These clowns will push themselves into extinction, we just have to wait. As far as heat goes, I reckon I've pretty much decided my future is wood. Just the dead stuff on the ground is abundant enough to heat my place every winter. I haven't moved there permanently yet, but I have fantasies about using it for hot water as well. I built a prototype wood gasifier to prove the principle to myself, so running an internal combustion engine for power from wood is my next big project once I get an actual drive to my property. |
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| Davo99 Guru Joined: 03/06/2019 Location: AustraliaPosts: 1577 |
I wrote a typical long winded post but I re thought and will spare everyone and Just say that was an excellent and accurate summation of the situation! I agree entirely. Before and during the war, my grandfather had a transport business. He had a number of trucks equipped with " Charcoal Burners". He went to enlist and was denied as he was deemed to be providing an " essential Service" and instead his little company was given a rather large Gubbermint contract to bring goods to and from the country town where he lived which had a large military presence to the city and vice versa. The claim to fame was his Converted 7 ton trucks could do the 200 Mile trip each way on just a Pint of Petrol. Ironically, several of his newly gubbermit subsidised trucks were tankers that carried Alcohol mainly for aircraft fuel from the distillery in the town to the city. He and his expanded Employees drove the 6 Trucks there and back 6 days a week for almost 4 years. I have read a lot about charcoal and wood burners for running engines and it's not an easy thing to do. Well it's easy to do, not so easy to get good power out the engines and have them serve a good long life. It's hard on them, real hard. There are many longevity problems but at least a stationary setup provides for more opportunity for refinements in the process such as filtering . To me though, it's still a fair way down the list of ways of achieving the goal. Liquid Fuels are infinitely easier and there are a number of waste oils that can be utilised and are much less difficult to use. If I had to use solid fuels, I'd be looking to a steam engine but they are neither easy to come buy nor cheap when you can find them. A couple of experiments I have wanted to try for a while was making those paper bricks and instead of using water to break down the paper which has to dry out, I'd like to try using Veg oil which would not have to dry and significantly increase the heat energy of the brick. Other thing would be boiling wood in oil. I think that would remove any moisture in the timber and if left in the oil to cool, should absorb an ( unknown) amount of oil and again increase it's heat value. I don't have the inclination to build an engine gasifier but I'd sure like to see one in action first hand. |
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| InPhase Senior Member Joined: 15/12/2020 Location: United StatesPosts: 178 |
There's a farmer in Alabama that has converted several trucks and a tractor to run on wood gas. His name is Wayne Keith. You can find him on YouTube. He isn't a prolific video maker and he keeps his gasifier design somewhat secretive as he has a book to sell. But he won the 3000 mile cross-country wood gas race a couple of times. My own gasifier works OK, but it definitely needs improvement. The key to to good wood gas is to heat the incoming air with the outgoing gas in a heat exchanger. You have to get the core hot enough to crack the tars to get the most energy. Then it's just a matter of dust filtering. I can get about 3 kW from a 5 kW generator with wood gas. It's actually simpler than steam and way safer. A steam explosion is no joke. You'd be lucky if you died. There's a guy in Australia, CNCmachiningisfun, that has done some interesting stuff with wood gasifier fuel processing automation. I have dreams of have a stationary setup that I can supplement a solar panels were system with. Maybe someday. |
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| Davo99 Guru Joined: 03/06/2019 Location: AustraliaPosts: 1577 |
Looks like winter has arrived. Tomorrow will be nice but after that, temps are going to take a nose dive for at least the rest of the week and more rain predicted. We got over 60 MM here during the week and we are nicely watered again here for the meantime. The local Rive went up necessitating a release from Warragamba that's full still and then some with more releases due later in the week. I aim to try and get the little Diesel heater set up tomorrow so I have that ready for the cold. I'll try to filter 100L of the Diesel I picked up from the brother in law the other week so that's ready to go as well. I had some reservations about far the 5Kw the heater provides would go but having run 1-2 Kw most of the week and seen that seems to be having an effect, 5 Kw in the proper cold may be more effective than I thought. Plus still nothing stopping me adding some electric heating. The solar will always make some power, not usualy enough on it's own but supplemented, should be fine. Really would have liked to have the Veg burner ready now and planned that last week but 4 days of rain Kyboshed that. Be ok if I could work in the shed but cleaning that out can't happen without a few days of fine weather either. I think all the DIY heating ideas are about to be put to the test. Hope yours is getting near ready to go Roger! |
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| rogerdw Guru Joined: 22/10/2019 Location: AustraliaPosts: 795 |
Well I've learned a few things over the last few days which have been a bit disheartening ... but I've come this far so I need to follow through for a bit longer. Tony had suggested I need to do an equivalent power test and I had been dragging my feet because I wasn't sure if I'd be able to work out how to do it successfully. My other test gear hasn't arrived yet, but on fri I pulled apart a heatgun and pinched the element. I then mounted that on a piece of insulating material. I lengthened the heater outlet tube by ~600mm and shoved the heater a fair way down ... noted the output temperature ... ... then I powered up the element via a variac until the temperature doubled. The heatgun is a 1,200 watt 240v unit ... 5 amps ... so the element should be 48 ohms, which it is! My first test was on Fri at 12:10pm, ambient was 25 though we had probably 90% cloud cover. The heater outlet was 33.3 ... so I needed to get to 66.6 ... which I did fairly easily at 100.2v. Of course power = V squared/R = 208 watts! Pretty miserable ... though of course only 6 tubes ... so all 18 should give 600 watts ... which is still miserable. I wondered about increasing the temperature by decreasing the airflow through the machine, which I did ... This time the power level was 89 watts. Wow, getting more miserable. Tony had suggested he thought I was going to need a high fan speed ... so I switched the fan to top speed ... pretty much all my tests so far have been on the lower of the two speeds. This test gave an output of 259 watts ... so a little better. Later in the day I had to go out, so switched off the fan. When I came back at 4:40pm I ran it again ... checked temp and then powered element to double the heat. This time it was 330 watts ... but this was not sustainable because while the fan is off, the tubes build up heat and can take 5 minutes to drop to an equalibrium where it will then remain depending on conditions. I tried it again Sat morning before I pulled it apart to build a full size model. Another dull grey day ... and at 10am we had 95% cloud cover, ambient of 15.5 ... and output was 197 watts. Again at 12 noon it was 199 watts. The results are pretty consistant so I'm fairly confident my measuring technique is ok. I'm not sure what I was expecting, but the 6 tubes cover an area less than one 250 watt solar panel ... and I'm pretty sure under the conditions one of those would have had virtually no output ... so I have to be happy with what I've got. I always envisioned a heater needing perhaps two lots of 18 tubes ... but that is still only perhaps 1,200 watts. Anyway, I had committed to build an 18 tube heater, so that's what I'm working on now. I have all the bits organised and ready to put together ... I just need to work out how to lift my 25 kg assembly couple meters in the air and slide the 18 tubes down into the glass tubes at a 45 degree angle!!! This is the heatgun element taped to some insulating material, which I powered up with a variac  Lots of use for my holesaw kit, at this rate I'm gunna wear it out. It sure is a pain prising the cutouts out of the saw though! This tubing is 150mm and cost me $10 from the junkyard ... but two endcaps cost me $10 each from Bunnings.  I stuck some wide weatherproofing foam across the holes between the two tubes and then used a smaller diameter holepunch to cut the holes. I bolted the tubes together, slid the tubes in and fed a wire through holes in the top of each tube so they can't slide out and drop to the bottom of the evacuated tubes like did happen with my first experiment. That was a pain trying to line up the holes, but it worked in the end. Oh, I forgot to mention ... the tubes only cost me $2 each ... but they were only 1,400mm ... so I welded 400mm onto each one. I've never welded aluminium before and I did a really crap job. I started with the oxy, some proper flux and rods ... eventually gave up in disgust. Then I tried the TIG and that was far worse, so I went back to the oxy. They'll have to do.  Cheers, Roger |
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| Davo99 Guru Joined: 03/06/2019 Location: AustraliaPosts: 1577 |
So were the Conditions! I wouldn't really expect anything else mate. The problem with solar heating is it's cold in the first place because there is no energy from the sun heating up the atmosphere / land. When there is no sun to start with, anything that relys on it to make power ( heat) is going to be limited too. Not every day will be like that though. I'm sure if you were testing over the last fortnights here you'd have been pulling a KW 1500w or more easy if you can get that from a 90% cloud day. Makes sense to me. The way you have it set up this would give more pressure through the tubes and force more air through although the temp dropping after a time would be something to watch for. I'm impressed you got that! Was raining here most of friday and my PV was bugger all. Bingo! I have a panel setup outside the office window I have been playing with a few days. It's connected to 2x 9Ah 12V sla batteries. Sure, at 24V the panel is being pulled off its curve a bit ( but not that much) but when it was raining here the other day it was barely generating enough power to push the 2 Little batteries float voltage high. Was literally doing closer to 9.7 watt than 197. Sure it is but keep things in perspective mate, thats under totally crap conditions. IF 6 tubes are 1 250w panel that would make 36 Tubes 6 250W panels and there is no way in hell you'd be pulling 1200W out of them in the conditions you describe. Ask me how I know and how easy it would be for me to demonstrate it... much as I'd prefer it were the other way. Mate...... You are trying to take on the welding equivalent of Brain surgery. Welding tubes ( thinwall) with oxy??? Literally no welder in the world would even try that. Aluminium has about a 3o threshold between coming up to welding temp and collapsing in a molten Puddle. Even TIG on ally like that would be Aerospace level welding. Oh yeah, I have seen vids of guys using those Hanrob guns welding aluminium cans.... I also know the guy that did it, a very long time friend of my father that has now passed away a few years back but that guy was given a welding torch instead of a rattle as a baby and spent his whole life welding every day. It's only air thats going to leak and that won't matter and no one will see it anyway so if they stay connected, job well and truly done! You have made a great setup of this, very impressive but I think in your excitement you may have done what I am sure many of us have done and got a bit hopeful with expectations. The reason I'm not doing solar heating is because I know from years past, even when I put up a laughable amount of panels, I can't make enough power to turn to heating I need. Yes my house is crappy far as heat loss goes but how many people you know have 25Kw of solar on their roofs? All that and we still come up short not only through the house but because as you found, nothing solar works well when there is no freaking sun! :0) The problem is, 90% of sunny days here are warm enough so you don't need heating or need minimal. When it's really cold you need lots of heating and the solar power isn't there. Same as at night. In this part of paradise, we don't get a lot of sunny nights and thats when the winter temperature plummets. Even the AC is prone to turning into a 1x 1.5M ice cube so this is why I'm going for combustion heating that creates heat not just effectively changes the form of the heat that is not present when I need it most. I think you need to think of your setup not so much as a heating devise but a cost saving one. On sunny cool days it will save you firewood or running the AC but it's not going to ever be able to provide your main heating needs. If you can keep the house warm 3-4 days and not need the fire going till 5PM, Bonus! If it's cloudy and wet and you do need to fire it up, situation normal. Seems to me the tube setup can potentially be quite effective, the flaw perhaps is your expectation are a little High. :0) This is like anything solar, a case of a bonus cost cutting arrangement rather than an absolute complete answer. |
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| InPhase Senior Member Joined: 15/12/2020 Location: United StatesPosts: 178 |
There is a product that goes by various different brand names. One of them is Alumaweld. It is like a brazing rod but is used with a standard propane torch. It isn't true welding but man is it strong. It's a great solution for the home shop when it comes to joining aluminum (<American for "aluminium"). |
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| Warpspeed Guru Joined: 09/08/2007 Location: AustraliaPosts: 4406 |
I bought a few of those aluminium brazing rods from e-bay to try after watching a demo on you-tube. Very impressive, but it needs nice clean bright shiny aluminium to work well. If the aluminium is old and oxidized and pitted, those brazing rods are pretty hopeless even after trying to get a clean surface. If you are buying fresh brand new aluminium parts, its an ideal way to make nice strong leak free joints with thin material. It works on thick material too, but its very slow and uses heaps of propane because the heat really spreads. TIG + argon is far better and much faster for heavy aluminium parts. Cheers, Tony. |
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| rogerdw Guru Joined: 22/10/2019 Location: AustraliaPosts: 795 |
Thanks for the kind words and the encouragement Dave. I realise now that I was expecting more than what was reasonable, at least with the numbers ... but I keep thinking back to the warm air pumping out of this thing in the middle of my back yard on cool days and under full cloud conditions ... and I'm still hopeful the whole experiment will be worthwhile. Yeah, we've had plenty of bursts of sun, but for only short periods ... so much cloud it has been hard work for it. Yes, that does make sense. Though I am amazed at just how well it can maintain a temperature provided the conditions remain the same. In perspective, it wasn't too bad. We had a lot of rain on Saturday. I was going to set up a pv panel alongside to compare outputs under the same conditions. I will attempt to do that once the bigger unit is assembled. I don't have enough experience with pv to be know what to expect, so again I have to be happy with my results. Yeah, but I watched a couple of youtube videos and it's 'easy' ... dunno why I couldn't make it work. Haha, I need a reality check on my abilities as well as solar power levels.Thank you, and yes for sure my expectations were a bit high. I think a large part of that was set by believing the sales hype for evacuated tubes ... though to be fair, they seem to maintain hot water systems quite happily if they have enough tubes ... and even in winter time. No substitute for experience. Can save a lot of pain. To be fair on myself, that was exactly my aim in the first place. As much as firewood is hard work, I wasn't expecting to be able to drop that ... just have some supplemental heat on those mild winter days and back off the burn rate of the wood. Exactly ... that's the issue with being eternal optomist. Cheers, Roger |
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| rogerdw Guru Joined: 22/10/2019 Location: AustraliaPosts: 795 |
Yeah, I've seen the ads on FB etc, but in my usual procrastinastic way I just did nothing about ordering any.  I'm sure it would have been perfect ... don't need any real strength, just stick together and not fall off. The aluminium is in great condition and using the scotchbrite belt on the multitool makes it nice and shiny. I think TIG is going to be out of the scope of my abilities ... at least without getting some lessons. Okay, well my wife came home from her ambo nightshift, so I convinced her to help put this device together before she had a shower to go off to her main job. We carried it up the ladders and got our daughter to line up the pipes. It had rained overnight and when we picked it up, the first thing that happened was a bucketful of water ran out the pipe, down my wife's sleeve to her armpit and soaked her ... whoops. Lucky she's a good sport.Anyway, got it together and with the sun already out could see the temp climbing nicely. Hooked up the fan and taped it on ... probably the first time ever in my life using duct tape to actually tape a duct!!! I added an extra 3 ft of duct to the outlet and used my element to check power level. This time the power was 752 watts ... which is pretty consistant with what I'd been getting earlier ... ... though I am still not sure if the IR device is a good idea for air temperature because I'm not sure if the localised heat from the elemment is not being picked up, despite my shielding. A proper temperature gauge might be a bit more accurate. I just came in to regroup and have a coffee ... and the postie had just dropped off several eBay items ... an anemometer, a power meter and a couple datalogging temperature gauges. Now I should be able to monitor things a little better.   Cheers, Roger |
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| Warpspeed Guru Joined: 09/08/2007 Location: AustraliaPosts: 4406 |
Its always handy to have equipment to be able to measure things, and the Chinese stuff is very cheap for what it can do. Cheers, Tony. |
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| Davo99 Guru Joined: 03/06/2019 Location: AustraliaPosts: 1577 |
I think that would be very helpful. It would put things in perspective. I know solar expectations well now so what you are reporting with your results sounds Impressive to me. Yes, 200W or so is effectively useless for home heating BUT, you'd be looking at 20w if it was PV under the same conditions. I would be but to be the pessimist of reason, a good result and a useful one can be a bit different. I tried it a few times with " Normal " Rods and wire and was wondering where I was going wrong till I asked someone that did it for a living and was told was something they would avoid if possible. There are these new rods now of some different material and they might be a lot different but I think it's still one of those things that takes much experience and a good bit of guidance to master. Yes but look at the comparison.... 5-8 KW would probably heat all your hot water and I'd expect a lot of people would need a lot less. 5-8 Kw of space heating in my house is keeping the chill off one large room for a day. The amount of power each application needs is vastly Different. I'll bet your wood heater is cranking out 4-8Kw the whole time you have the thing lit. That fan heater I have in the Kitchen area is going through 8-12 Kwh a day and that is just basically offsetting the heat losses and keeping the furniture warm. I have one in the lounge and another in the office. I have only been running them on low so far but pretty bloody sure thats about to change even in the next 24-48 hours. Time to get the diesel heater running.... Which is going to seem really odd on this perfectly clear 24o day as it is here now. Tomorrow when it's 12 and raining again, things will be different. I might reset the meter I have on the fan heater in the kitchen and see how much I pull in the next week which is suppose to get back to winter temps. I just came in from hooking up some more panels and setting up the inverters as far as which one gets what array. Keeping the phases somewhat balanced is something I have to watch. One is 70 KW behind atm and the other is 200 so that phase is as I speak getting 3.5 Kw of power and the other is getting 900W. bit of luck in 5 weeks when the next meter read is due they will be more balanced up. And give you a lot of insight into reality as well. That's worthwhile in it's own. Never cease to be amazed how much wood one can go through in a winter but when you look at it, the energy density is so much less than liquid fuels which is why I'd love to have a converted heater. Oil is for lazy people like me because it is just so much less work and you don't need the investment in gear to process it either, especially not just for burning rather than going in an engine. Ah, see, being the eternal pessimist, I rarely over estimate or am disappointed. At worst things turn out exactly as I expected or alternatively I am happily surprised and impressed. |
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