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Forum Index : Other Stuff : Anyone do any real form of " alternative" heating or cooling?
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Haxby Guru  Joined: 07/07/2008 Location: AustraliaPosts: 423 |
Yes, it works both ways. One disadvantage is that you don't get that nice warm window feeling in winter. |
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| Davo99 Guru Joined: 03/06/2019 Location: AustraliaPosts: 1578 |
The other thing I see is the investment in the process. Chainsaws, splitters, trailers to haul the stuff around.... Dad has a LOT of Chainsaws mainly for this and the splitters I bought him some years ago for $700 Odd is now about $2500. One has to consider the all up cost of the heater and equipment as well as the cost of getting the wood and say well how much power does that buy me and how long would that last? Not sure what a heater is, $3K installed? Another $1500 for a decent splitter minimum Saws, fuel getting it..... My mate whom owns a tree lopping business and sells firewood says it's the most expensive form of heating of all. He only sells the wood to get rid of it but as he points out, the machinery he has, the fuel to run it and the unreliable people he has to employ to process it make it a cost to him if anything but if he puts the price up, then he sells nothing at all and is stuck with it. The machine he has is worth a fortune but even that at scale is a relatively slow process to produce the split timber especially for it's size. I do like the wood fires and agree with your Mrs, there is a lot of comfort and contentment factor which is why I bust my innards every year trying to get enough for Dad. I have noticed particularly with oldies, the more wood you give them the faster they go though it. Same thing happened with my neighbour at the last place. One year I organised more wood and cut and split it for her than shed ever had before. It was stacked 6Ft high along the back of the house and about 30Ft down both sides of the fences. Should have lasted her years. I think it was about 8 ton all up. She ran out in the first season. Couldn't believe it but when you would go up there, she would be in a t shirt and shorts and the place was a cosy 40oC! Only made that mistake once. Dad is a bit the same. The bigger the pile at the start of winter the faster it disappears. I'll have to get stuck into it when I go back up. Ideally you want to have it dry over summer but too damn hot to work on. When I was up there a month ago My shirt was literally wringing wet from perspiration like I'd been under a hose. even the top of my pants were wet. Wood cutting and splitting is not a summer sport that's for sure! |
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| Davo99 Guru Joined: 03/06/2019 Location: AustraliaPosts: 1578 |
That would suit me fine! The ensuite windows are shaded in winter making for cold radiators and in summer the heat blasts through making it an uncomfortable place to be 6 Months of the year. A lot of the time the winter sun isn't very effective anyway. I was just in the front loungeroom and picked up something black sitting in the sun and was surprised how warm it was. Very bogan but I wonder if some black painted thin MDF boards on the floor would do anygood at all? I tried some black curtains in the other loungeroom before and couldn't detect any worth while warming from them. |
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| Solar Mike Guru Joined: 08/02/2015 Location: New ZealandPosts: 1138 |
The amount of energy entering your sunny window into a room can be considered a constant, placing a black object inside the room in direct sunlight may heat that object up but will not affect the temperature in the room, as normally all the sunlight entering via the window is absorbed by the room contents and converted to heat. Cheers Mike |
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| Warpspeed Guru Joined: 09/08/2007 Location: AustraliaPosts: 4406 |
There are two very different mechanisms at work here. Radiant heat (from the sun) will be reflected, so its very good for keeping out the heat from direct sunlight out. You know what happens when you park your car in direct sun.... There is also be thermal conduction through the glass which will not change. So in winter you still have very cold glass. That is the purpose of double glazing, to provide a heat insulating barrier of still air. So basically, the trick glass for keeping out the direct sun in summer, and double glazing with ordinary glass for keeping the warmth in in winter. The effects are very different. Edited 2021-04-01 14:28 by Warpspeed Cheers, Tony. |
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| rogerdw Guru Joined: 22/10/2019 Location: AustraliaPosts: 852 |
I don't really know enough to argue ... but I'm struggling a bit with this statement Mike. If you had 10 or 12 hours of sunlight entering a room and it falls on some curtains or blinds ... or even just on a lounge and some carpet ... ... or alternatively falls onto the concrete or tiled floor ... surely there's going to be a difference in the temperature of the room eventually. Isn't that the whole point of passive solar heating ... where a building is set up to absorb the sunlight onto the floor or a thermal mass ... to help raise the temperature of the place in winter eg. Cheers, Roger |
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| Davo99 Guru Joined: 03/06/2019 Location: AustraliaPosts: 1578 |
Yes but the energy entering the room is the same no matter if It falls on a white sheet or a black board. The room will heat up ( if the heat gains are more than the losses) but in reference to my question about black boards, it would make no difference what I put in there because the amount of heat passing through the window will be the same. I can't suck more heat in, I can only make certain objects absorb more of that heat. I think in what you are referring to, the energy absorbed into a thermal mass is to dissipate it out when the ambient temp drops slower than the heat would be dissipated to the air. It's the difference between hot and cold that makes the thermal mass give up it's heat where as air as little to no thermal mass.... Far as I'm aware, so as soon as the air is dissipated, the energy is lost. The explanation was a good one and made me understand completely . Thanks Mike. I can see where you are coming from too Tony. I believe the terms might be radiant energy for the sun and convective/ conductive energy for the cold. One travels as waves, one travels through physical matter. The double glazing stops the convection but not the radiation. Hopefully I'll make a start on my oil burning heater tomorrow and get some things done over Easter. 10Kwh is only about 1L of oil an hour. The losses may be significant so may require 2L hr to be burnt to get 10 Into the water but even still, having stable and reliable combustion at that level will take some careful design. An output of 200, 600 or 1000Kwh is easy but it's the lower outputs that get more tricky. The key to oil is retained heat for vaporisation. Too much air takes too much heat away so the correct air fuel ration gets critical. I may have to build a downsized burner so I can run it hot at reduced outputs. Once I can get that sorted, the rest is just basic construction. I wish the place had a Hydronicaly heated slab where I could set up a 200KW Heat exchanger and blast even 50 Kw into it. Then again, might require a slow heat up to avoid thermal stress and cracking. Combustion power seems a lot more sensible than electric for this sort of scale that's for sure. I wonder what the typical energy capacity of a slab would be and the temps they are held to for this type of heating? |
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| Warpspeed Guru Joined: 09/08/2007 Location: AustraliaPosts: 4406 |
Slab should make a very good heat reservoir, as long as its well above any groundwater. In very cold climates, there will be permafrost at some shallow depth below ground level. Even in mid summer with outside temperatures well above freezing, you dig down maybe a foot or two, and its solid impenetrable ice. No buried pipes are possible, no sewers either. The same holds true for a heated slab. The heat does not conduct well through the ground, it acts like a massive reservoir of heat (or cold). But to achieve that heat storage you need to keep it at a constant temperature. Its no good saying it was hot yesterday, but today its cold, so I will just heat up the slab to get warm. Its entirely the wrong approach if daily temperatures are all over the place as they are here in Melbourne. Much more suitable for Canada or Russia where its freezing bloody cold for almost all of the year. For oZ, my own personal preference is for minimum thermal mass, and good insulation with some passive heating and cooling architectural features. Then rely on heating and airconditioning to maintain comfort, but ONLY in occupied rooms. I live by myself, but have six gas space heaters and four airconditioners. But only ever run one of those in the particular room I am in at any one time. All are grossly overpowered for the room size, so getting a room comfortable only takes minutes to heat or cool the air. The wall surfaces, furniture etc, may take maybe an hour to stabilize, but air temperature is the thing. So you need powerful equipment, but it costs no more to run, as a room thermostat quickly throttles it right down. Cheers, Tony. |
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| Davo99 Guru Joined: 03/06/2019 Location: AustraliaPosts: 1578 |
I was thinking about a different type of solar heating today. Simply a Large Diameter 3-400MM Black plastic tube with a fan pushing air from the far end and inflating it and pushing air into the home through a window. A restriction should create a positive pressure and allow the tube to inflate without support. Based on what was said earlier about relative efficiency, I though this might actually produce some useful warmth in the sun if the tube was say 10M Long. Kind of like the geo systems without all the cost, mess and every other negative. Don't know if black plastic tube like Builders plastic is available but I have welded it together before with a soldering iron and it was 107% successful. Is there anyway to estimate the heat might get out of such a setup For area of plastic exposed to the sun? Other thing I was thinking of today is if anyone knows of any temperature comparison Chinese thermostat boards? I'd like to have a fan outside and have it set so it came on if the outside temp was warmer than the inside Temp. Haven't started on the oil heater yet, been doing a lot of outside work in the garden. I have started the Controller Box. Timer for the fuel pump and a PWM controller for the the blower speed. Might be an idea to add a temp readout for the tank as well. |
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| Solar Mike Guru Joined: 08/02/2015 Location: New ZealandPosts: 1138 |
Wont be very efficient, will loose too much heat. You need a large surface area exposed to the sun, and covered by a glass, clear plastic etc, creating a sealed lid to make it more efficient. If you have a suitable rise to the window, then the setup will thermo-syphon, no fans required. Say at 50% efficiency then 2 sqm will output approx 1Kw heat depending on strength of the sun. See this article here Thermal Siphon The site has lots of ideas and examples. I made a similar arrangement for drying food, the warmed air exits into an old stainless steel dish washer sitting on a stand with a chimney fitted, racks for fruit/other food items placed inside and easy access with the big opening door. Cheers Mike Edited 2021-04-03 21:16 by Solar Mike |
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| rogerdw Guru Joined: 22/10/2019 Location: AustraliaPosts: 852 |
That's an interesting idea Mike. At least the plans are easy enough to understand. Ryanm put a link to the homepage of that site a while back and I've been going through some of the material, though hadn't seen that one. Thanks Ryan and Mike. There was one video Dave, that made a lot of sense and I think is worth watching ... https://www.youtube.com/watch?v=gBLQ2ZUeP7w They came to the conclusion that their "Screen Absorber Collector" gave the best result of their tests ... see their conclusions here ... https://builditsolar.com/Experimental/AirColTesting/Index.htm#Conclusions Dave, your idea of a 10 meter plastic tube probably comes closest to their "Empty Box Collector" ... which had only 50-60% of the output of their best type ... the Screen Absorber Collector, which is still pretty simple and cheap enough to build. Cheers, Roger |
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| rogerdw Guru Joined: 22/10/2019 Location: AustraliaPosts: 852 |
That explains your situation and your preferences well, and sounds like it works best for you ... especially with low thermal mass. A slight problem for me would be that with six gas space heaters and four airconditioners AND several young adults ... they'd ALL be on flat out ... and the aircons would be on cold coz someone would be finding it too hot! I can try and educate till I'm blue in the face, but some people can not or do not want to comprehend energy efficiency. Maybe until they are paying the bill perhaps.  Having said that, we were in an old stone home for years and now in a brick veneer home on a slab ... so we live with a high thermal mass. Again, it's a matter of management and summer times closing blinds and running ceiling fans during the day, opening up the house in the evenings and overnight to allow the cool breezes to bring the temp back down again before the next onslaught of heat. And in winter time, running the wood heater 24/7 which warms the whole house up to a liveable temp ... but still putting a jumper on if we're a bit cold instead of cranking up another gas or electric heater. It doesn't help that we have a big open plan house, so it's difficult to warm or cool specific areas. I think that is why I have been looking at options to warm some additional air during the day to pump into the house, so it needs less wood or electric energy to carry it overnight until the next day. Of couse any warm air that is pumped in, needs to warm the thermal mass otherwise it is a waste of time altogether ... so it needs to be directed as efficiently as possible. And just how that is done or what method to use, is my big question. I have mentioned before that I can walk barefoot down our passage and the gradient of heat is quite noticeable the closer you get to the heater. You can feel it start at least 20 feet away. The only way the tiles can heat is by radiant heat, over some weeks of time ... so I believe it is only the warm air produced by the heater that eventually warms them. The heater pedestal is barely warm to the touch, so no transfer there. As Mike and others have pointed out, air is a poor carrier of heat ... so I need a better method of transferring heat to the slab and the brick walls. Cheers, Roger |
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| Davo99 Guru Joined: 03/06/2019 Location: AustraliaPosts: 1578 |
I figured as much as at least half of the area will not be in the sun and radiating heat out. That said, I'm not sure outright efficiency is the most important factor here. This could be so simple to build, Tube of plastic maybe with some string over pegs to stop it blowing away in the wind, and also cheap, any worthwhile heat would be good. If say the 10M Length which would be easy to accommodate for me put out 2 or 3 Kw of heat, if that's not dreaming, then that would be OK. I could use a car fan running off a panel for the air source so energy input there not an issue either. Seems Like one could get plenty of surface area for not too much money with this stuff and plenty of larger sizes available. Plastic sheet tube Great on a sunny day but when the clouds come out..... Edited 2021-04-04 00:15 by Davo99 |
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| Davo99 Guru Joined: 03/06/2019 Location: AustraliaPosts: 1578 |
Fails the Very Test the Mrs and I "discussed" ( I was told in no uncertain terms about) this morning.... I am NOT allowed to be turning the place into a Hippy, free energy camp. Yes, I can have a separate generator shed in the form of one of those little Garden Sheds which would not look out of place, NO, I am not having solar trackers, Windmils on the house or shed, we are not getting sheep and I will not be shearing them for her to get a spinning wheel and make yarn for her to knit shirts and underwear. There will be no 14 Ton steam engines up the back, No diesel generators taller than she is or the size of a small Car Like at the Vintage machinery Club. No one will be stoking boilers for heat or power, There will be no drilling rigs looking for water and no ploughing up the back yard to grow produce but I can cover the veggie patch I have behind the shed and make a greenhouse out of that if I wish. Hmmm. I do not have a clue where she gets these Ideas I'd want something like that? Strange woman. Why would I want Knitted woollen underwear?? Doesn't know me as well as she thinks. I'm sure large solar hot air heaters would be out too. :0( I only have a wife and 24 Yo daughter and I can relate to that entirely. They are diametrically opposed as to their comfortable temp levels. Daughter will literally have a sloppy Joe on in 30O weather. Mrs is putting on the AC if it hits 22....Ugggh! I hear you but the trouble is the wife IS paying the bills and still doesn't care! Last few days have been Beautiful here, Bright, very warm, perfect although charastically, the night temps plummet. The house has been holding temp, on the cool side. I brought down my Tube Ventilation fan and put that outside a window to blow the heated air in when it's been 25 or so degrees. Not happy with that, what we need that for? You were the one complaining about it being Chilly last Night ( for once!) I'm trying to warm the place up before it gets cold. Suffice to say the logic was not accepted or approved. This is my fathers theory and I hav found it hard to argue with. He runs his fire 24/7 but on the minimal firing though the day when he's up the back. Still puts out useful heat though. His position is you leat the fire go out, the whole house and walls, furniture etc Cool then you use just as much wood trying to get comfortable again which doesn't really happen and then you go to bed anyway. I can well see the practical effects of this both sides and he's right. Been thinking to run the house pretty warm through the day to try and heat soak it for offsetting the night cold. I think of mine being the other way as worse. Our Home is about 30 M long and no matter where you put heat or how hot it is, a room or 2 away and it's like ice and the main lounge and the main bedroom being at opposite ends have zero bearing on each other. Only way to get the warmth around somewhat is to use the AC on fan if not actually working. As Mike and others have pointed out, air is a poor carrier of heat ... so I need a better method of transferring heat to the slab and the brick walls. Poor or not, the only way I can see to put some heat soak in my house is to have warm air. The kitchen is 70+ SqM of tiles that is a giant cold radiator in winter and no way to warm that other than electric blankets.... which I'm sure would fail the wife test. After looking at the detail in those solar air heaters, I'm more encouraged to put some more money and time into the Oil burning heater. Guaranteed heat output Night day or any weather and compact and practical. |
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| rogerdw Guru Joined: 22/10/2019 Location: AustraliaPosts: 852 |
Haha, yep ... there's always that pre-step we've got to get through ... and doesn't matter how sensible, clever or money saving it could be, some things are just never gunna fly. Having said that, I have been pleasantly surprised at the support I've been getting to build the Warpinverter, so if I can make that work my next project may have more chance. I always used to hear of government buildings and hospitals etc in regional areas that had their airconditioning controlled from down in the city ... and think it was crazy ... but I can now understand why because there'd be a constant battle by individuals to set it for themselves and it could never work for everyone. Oh well, that would take the edge off it a bit for me, as long as the rest is manageable. Haha, damned if you do and damned if you don't. So tell us, how did it work? I think mine is more laziness ... it's easier to stoke it up again in the morming so it doesn't go out ... then throttle it back until late arvo and stoke it up again. Yes exactly, that makes the most sense to me ... especially seeing we still get a lot of reasonable days during winter. Might as well take it when we can get it. I just need to work out how best to transfer any heat. Maybe I can put one of those thermal blankets under a large floor mat ... then blow hot air under it for a few hours, moving it around from time to time. That'd have to warn up the tiles a little more ... course the execution of the plan might have to happen while she's at work. I might be in trouble if she goes for a trip on one of my hover-mats. Yes, seeing you have skills in that area already ... and the biggest advantage is that you get to choose when to run it ... and not only when the conditions allow. Cheers, Roger |
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| Davo99 Guru Joined: 03/06/2019 Location: AustraliaPosts: 1578 |
It was certainly less chilly inside Last night. Today would have been good. We went out and it was nearly 30 here so bit hot when we came home. She came in and said oh, it's nice and cool in here without fans blowing the heat in. Yeah, and it will seem real bloody cool tonight let me tell you! When I split the wood I always make sure to leave an amount of Real Big Chunks about as bit as can get in there. I call them " All Nighters" so he can put on of them in with whatever to fill the thing and it will still be going in the morning. Only complaint he has is it's difficult for him to lift them in there but he seems to manage. Another beautiful day here today but the rest of the week is supposed to be crap so any solar input will fall off the cliff as will the temperatures. Had a great run for a week now so can't complain. Not sure if this is in jest or serious but the KWH it would take to warm a slab given it's weight alone would be significant and that's if you CAN get the heat in there. I can see air would be a poor conductor in this way, much better would be to have something direct like on of those Silicone mats with the heating element in it but I really think this would be like shoving the proverbial up hill with a feather. Electric I can see would take a Biblical amount of electricity and I can imagine unless the slab was on foam or something inusltive the losses would be equally as fearful. I think that's really a job for combustion heating where many 10's of Kw could be thrown at the task. Cement has a much lower energy density than water but when you are trying to heat up around 50 Tons of concrete. Yes, the burners are relatively easy, the Heat exchange will take more thought. Still in 3 Minds if the water heater will be enough but spose if I run it enough it should be. Even adapting a 100Kw Spa heater HE is a bit of a challenge for me anyway. It should be pretty efficient though. It's really just trying to package it all. I think I'll get some sheet steel Cut and weld Directly to the HE and make the whole thing the cabinet and support. Think I'm worrying about efficiency too much when I should just be happy with Brute force to get it going and then worry about the fine Tuning. The main thing I have to worry about is diffusing the flame so it does not touch the HE itself. A baffle plate would probably help but may need to go to a secondary air as well. A large open top swirl burner may be the easiest thing though. One thing that would never be a problem for me with this would be fuel supply and it's a damn site easier to collect oil than it is to process timber. I have been looking for an old wood burner to test some oil conversions on. If I could find some sort of a Boiler that I could put outside, that would be awesome. |
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| rogerdw Guru Joined: 22/10/2019 Location: AustraliaPosts: 852 |
Yes, we do the same here ... though ours has an oven below, so the firebox is not overly large and it's hard to get enough wood in there. Sorta wishing we'd not got that style as while the idea sounded good, we don't really use it as much as I'd hoped we would ... and a bigger firebox would be handy. Nah I am being serious and I'll tell you why. We've got what seems like half an acre of tiles stuck directly on the slab, which are wonderfully cool all summer ... but they do actually warm up in a gradually expanding radius the longer the wood fire is burning. Takes a few weeks. My point is that if the wood heater can warm up a substantial area of tiles and associated slab, simply through the air in the house being warm ... surely there's a way I can help that along. If I can use a collector to feed in warm air to soak the house during the day when it's available (like you suggested earlier) ... then I can speed up (or suplement) the warming of the tiles and the slab. It's not like I expect to warm it in an afternoon ... this would be a whole of winter operation ... just like the 24/7 burning of wood. So while it sounds like and may well be a silly idea ... I'm trying to work out how I can get more warmth into the floor. Yep, agreed. So your thoughts are to heat a shipload of water ... then pipe that into some hydronic heaters inside the house? That has a lot going for it. Cheers, Roger |
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| Davo99 Guru Joined: 03/06/2019 Location: AustraliaPosts: 1578 |
The Mrs was saying she would like a wood fire and I said well why don't we get a wood stove? My aunt and uncle have one and I have been fascinated with it. heats the house, cooks the food and for them heats the water as well. Mrs of course doesn't want that, why would we need 2 Stoves? More dual purpose the better I reckon. Well let me know if you find a better way because I'd sure be interested. Well, yes, and No. If I have the burner constantly Firing I don't need a lot of water. If I have a lot of water I can turn the burner off and have a reserve for the Night/ Morning. The question is how much heat will I need? I don't really know, I'm just trying to guess at this stage. A couple of 400L water heaters would be fairly easy packaging with about 60Kwh of heat storage. The idea I have atm is to pump the water though a car heater core, put that in front of a tube fan which sucks the air through and exhaust it into the house though a bit of Duct through a window in the middle of the house. The return air for the AC is there so hopefully that will distribute it although I may also dump it in the kitchen and see how it goes through from there with the AC Fan. I hadn't thought of Multiple outlets. For the initial idea I'm planning to use a converted gas water heater. That has limitations I'm concerned about WRT the amount of heat I can get into the water and the diameter of the outlets being 3/4 although there are 2 top and Bottom. I am thinking of doing my own HE which would allow a lot more heat transfer and I can make the in and outlets any size I want. The other thing is to make the 100Kw spa heater cores I have into a workable package which would probably be the cheapest and most efficient way but poses some challenges. I'm really spinning a lot of things in my head atm and not sure which way to go. I'll do some measuring of the heater core tomorrow as I may have found a solution for that. Yes. Oil has been a BIG asset to me over the years. It's a fantastic energy source that has everything going for it like all liquid Fuels. I would Ultimately like to go to Co-gen but that's another step away yet. I could set it up tomorrow, positioning and packaging the setup is another thing though and whether or not I can get it quiet enough. We have a lot of Grandiose ideas of what we want to do around the place and only so much space around the house to locate things so it's all bit of a puzzle atm. I think a lister would be best for that but not happy with the knockoff I have and genuine examples are hard to find. I may be able to go the big single Cyl water cooled Kubotas but they seem very mechanically noisy. I have an inline Kubota engine on a Mower I'm eyeing off as that seems relatively quiet, smooth so as not to transmit ground Noise and has plenty of power. The mower it's in is rough but it does work. Shame to wreck it especially as it's a fairly unique model so I'm holding off on that idea. Trouble is I paid less for the whole thing than what I can get the motor alone for. Think I'm really just going to have to Build a big box, line it with soundproofing ( insulation may be good and cheap) and see how I go from there. |
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| Haxby Guru Joined: 07/07/2008 Location: AustraliaPosts: 423 |
It's usually the exhaust that is the loudest, so in a permanent setup you can change the exhaust to use a much much bigger, better, quieter one. One thing I had put a lot of thought into was a stationary Prius engine based generator that would use either LPG off a big tank or piped natural gas (if available). That could run a co-gen quite easily, and very quietly. It wouldn't be louder than a split system air con. After considering all the options, and doing some calculations, I'm now a big believer in reverse cycle air conditioning split systems coupled with the biggest solar system you can install. From a maintenance point of view, you don't have to do anything, and the system should last a decade or two with little input. No chopping wood, no gas bills, no petrol, no diesel, no noise, no moving parts... And you can add to it if necessary. The cost of solar has halved (or more) in the last 8 years, while prices of gas and oil are increasing. Storage of solar is still a big issue but if heating/cooling is the biggest consumer, you can store hot/cold water in a big tank, and cook during the day while the sun is producing. That leaves just lighting and TV circuits for the night time, where only a small battery is required. |
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| Davo99 Guru Joined: 03/06/2019 Location: AustraliaPosts: 1578 |
On These stationary Diesels, often the intake is as loud or louder than the exhaust. They pay attention to quieting the Exhaust, not so much to the intake. I have tested a good variety of little Diesels by putting a rag over the Muffler and then one over the intake and the effect is noticeable on both, but often more pronounced on the intake. They are pretty easy to quieten as you say with bigger Mufflers that can go on the intake and the exhaust as often air-boxes are not enough on the intake particularly with the China Diesels in various flavours. The little 4 Hp I just bought is surprisingly mechanically noisy but then so are the Yanmar Vertical Cylinder knockoffs. I don't know how they set them up at the factory or if they set them up at all but often the timing is so advanced and the " Knocking" so bad they would surely self destruct in little time if they were not pulled back. I have run these on veg oil which has far slower lightoff than diesel and they still sound like they are hammering the piston into submission. Pulling them back quietens them a lot and I suspect increases life expectancy quite a bit as well. I have seen a couple of these on the net. Large ( for the job) petrol engines are easy to make quiet and can be very fuel efficient as well. Always wondered if it were Possible to set up a petrol engine to run on Diesel/ oil with spark Ignition assistance? Might be able to be done on Diesel with something like a vaporiser to turn the liquid into gas. Waste oils would leave a lot of deposits so would need cleaning regularly or the oil would have to be pyrolised and refined before use. I had around 25 Kw of panels last winter, admittedly all but about 9 Kw facing west but I couldn't keep up with out AC demands. I was running it as sparinging as possible and we were going through up to 80 KWH a day. Yes the house is Big, Yes night temps are regularly zero ( but the days are often 20) but the days are just too short to really make a lot of power.I had the inverters well overclocked and they ran at at least 75% capacity even on hazy days but the hours just aren't there to make the KWH even if the KW output is good. IF you had a well insulated home, could have your arrays in 3 orientations and at least double inverter capacity of a Minim,um of 10 KW and the conditions were not too severe, one might be able to get by on solar without pulling too much from the grid. It's all horses for courses but I couldn't make it work for me. OTOH, 80 Kwh is 8L of oil, call it 10 for inefficiency and not every day will be that cold. Might sound a lot but at 10 L a day, I could probably get through winter with 600L which isn't hard to get at all. Collect over summer and wouldn't be hard for me to get 1000L if I wanted. As I have said, I think electricity is weak for heating, even multiplied by AC but the energy density of liquid fuels is a lot different. Again though, for a smaller, well insulted place with maybe a more efficient AC than I have and a BIG array, it's definitely as you say the easiest and most convenient by far. I have a lot of roof although not all of it ideal but if the house was 90o turned and the roof was clear, Might be OK with the shed. Ideally I Think I'd want about 40 Kw of panels. Was reading the other day, for sydney the Multiplication factor for generation is about 2.4. That means for every KW of panels, You'll make a minimum of 2.4 Kwh on a sunny day. In summer, it's about 6. Having a huge array isn't about making mega power, it's about making the minimum you need when you need it most, in winter. This was my thought but it doesn't really help me. I have been doing a lot of number crunching and testing and it's still just hard to generate the amount of power I would need in the daylight hours available. Of course if you store solar heat in a tank, you are likley going to resistance heating unless one uses some sort of DIY Hybrid heat pump into a large tank and resistance looses the multiplication effect of Reverse Cycle. I wonder how much hat could be made from a DIY setup where there was a small engine Driving a car AC compressor? The Condenser could use the waste engine heat quite easily and if it was fed even a 20o supply of air, that would certainly make it efficient I would think. Have to talk to my AC mate when I see him. One thing I was thinking of was putting a draft burner near the AC unit so it could suck heat off the burner which should also make a big difference to the energy use and efficiency of the heat Pump. The efficiency of the burner would be lousy but as the heat isn't costing anything, all good. Even a little heat in the real cold would make a big difference if it keeps the AC on it's efficiency curve. I have frozen up the outdoor unit a few times when it was really cold. Heating is definitely the biggest energy use for me at the worst time. I can run the AC Night and Day in summer because I make plenty of power to do it but in winter when the days and solar is short, things are different. I'm lazy and so is the rest of the family. Lifestyle Modifications while all the rage now for this sort of thing are not high on our excitement list. I have been following a an extensive thread on another forum and no matter which way you cut it, even DIY batteries just seem to sneak in as being worthwhile, but often not as against buying power. Even at an all up cost of $200 Kwh installed and finished, it's pretty border line for a 6 Yr payoff. That's a bit long for an impatient person like me. Then again, I can well see value in the peace of mind in not getting bill shock and always knowing what you are likely to be up for. I want to use oil as my battery. Yeah, it's more stuffing round but I guess you pay one way or the other. |
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