Author Topic: Phase Change [heating with solar]  (Read 3230 times)

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Bruce S

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Re: Phase Change [heating with solar]
« Reply #27 on: November 09, 2017, 12:35:52 PM »
Now that overnight temps are in or near the kill the tomato plants' temps
I wanted to post a small update.
The idea of using tallow is still a valid one, however since most of our days have been overcast enough to not heat up the water in blacken containers and not even close enough to warm the little bit of tallow .
The test plant has taken some pretty big hits. 1/3 of the plant is pretty much dead.
On a brighter note I've been getting vegetable shortening ( the stuff knock-off Crisco ) that is either expired or rancid.

Here's a picture of how I built them. I place these in a #10 can that is filled with water 1/2 way. 3 of these have been great for keeping the cold away from the plants.

We are still getting tomatoes too ;-)
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OperaHouse

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Re: Phase Change [heating with solar]
« Reply #28 on: November 09, 2017, 12:49:38 PM »
Have you tried the underground sewer pipes with a small fan blowing air through through them?

Bruce S

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Re: Phase Change [heating with solar]
« Reply #29 on: November 09, 2017, 02:05:18 PM »
Not yet, that will need to wait until spring/summer dig time.

I do know that the composter helps keep the little plants warm too. I covered a volunteer tomato plant with a sheet blanket and that plant did better than the ones trying to stay warm using water/tallow combo.

We tend to run our compost bins hot due to "critters".

 
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george65

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Re: Phase Change [heating with solar]
« Reply #30 on: November 09, 2017, 04:41:04 PM »

Looks like a Wick in the middle of it.  Have you been making giant candles? Might be a viable solution!

I'm having trouble with my Tomato and other seedlings.  They either get burnt to a crisp in one hot day and are dried out or the things are drowning with too much water.
An old upright freeze died in flames the other week so I moved it up the back and am using it for seed raising.

I put a large LED Lightbar I wasn't using on the top shelf and have that connected to a battery charger and a broken solar panel on the roof behind.
During the day, the panel makes all the power and the charger amps drop to nothing. as the sun goes, the charger takes over.  Just direct connected and seem to work fine.  I thought the panel would take power from the charger when not generating but the amps are the same and I remembered, like the charger the panel has diodes which should prevent that.

At night I close the fridge door as the temps drop pretty well here and that keeps everything nice and toasty and then let the warmth and air in during the day.  Had it going about a week now and the seedlings are coming on great and the seed is germinating nicely.
Was thinking of a small fan to move the air and warmth around and also maybe put a fogger in there on a timer.

I saw some small cheap heater elements off Fleabay that are 12V so was also wondering about putting them  in some water at the bottom of the freezer for when winter comes.  They are constant temp, anything from 120 to 250C  but with a 25L drum of water I can't see them getting near boiling it.  If they do I'll add more water for lower temps and more thermal mass.
The freezer did have excellent insulation,  l When it died the food was still properly frozen ( even the ice cubes didn't melt) for 3 days.

I had 3 tomato plants in 25L drums that were 3 years old. Unfortunately last year I went away for a couple of weeks and it rained the whole time. Poor things must have drowned because I lost them all which I was really peeved about.  Going to put some more in shortly and see how long I can keep them going. I put my LED's on them at night  which probably threw enough warmth to keep the frost off, give them much needed light and annoyed my mongeral neighbour as well.

Kinda miss not having the mongeral around to upset. Neighbors here are good so I have all these fiendish ideas going to waste now.  :0)

Got the new controller finished for the aeroponic system so have to put some lettuce in and get that going.  I actually prefer that to gardening with soil.
I want to do a whole wall of grow towers but first I have to get a handle on the climate and weather here.

Bruce S

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Re: Phase Change [heating with solar]
« Reply #31 on: November 10, 2017, 08:43:16 AM »
I was doing something similar with a min-fridge that I rescued from work 3 years ago ( had a blown start relay). It died of a opened internal winding .
New neighbors complained of "open storage" plants are now inside in an old galvanized wash tub ( free) along side 1M kale plant. Shock is over and cute new snow pea sized tomatoes showing up.

Lights= I went with 0.99/ea 21CM USB based LEDs built for plants. These are 5Vdc1.0A units that I run at 5.vdc 0.8A ( I use a USB 110VAC) adapter so I can make use of mechanical timer for 16 hours of light. The backs get warm even at lower power but plants and moth eggs love 'em.

Moth worms all but destroyed the kale!Seems the extra warmth interrupted their winter sleep and they chowed down.

YES, I built over sized paraffin / solid veggie oil candles  ;) , not sure just how long they burn but they're still on in the morning. Solid veggie shortening was nearly free paraffin candles we can get pretty cheap at thrift stores last snag was 50 for $1.
I use wife's cooking time to melt shortening.

I got the idea from a U-tuber in the UK.
https://www.youtube.com/watch?v=jRehAKZ7uHU
 I might try it as big as he did , but the little ones allow me to make them while oven is on. Tins are recycled canned fishes empties

My little morningstar solar controller finally went belly up and near killed my 65Ahr 12Vdc battery. So I'm now baby sitting it until new and improved unit arrives. I went with a higher end 30A 12/24 Vdc unit this is programmable to cut off power at a setable voltage.

Basil is weak in hydroponics so I use a hybrid system similar to a dutch bucket system for them. Could be the stems are too heavy for it. Wife's school grows them using hydroponics and they'res are huge
Containers are free coffee containers PVC tubing is free from worksites, all I buy is elbows and grommets.

I may start a separate thread for those


 

 
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george65

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Re: Phase Change [heating with solar]
« Reply #32 on: November 10, 2017, 05:09:37 PM »

Moth worms all but destroyed the kale!
 

Geez, there is a scary similarity!!

Had the exact same problem this last couple of weeks! Kale was disappearing before my eyes! It was in pots under the verandah waiting to be planted out.
I'd get the grubs and there would be more the next day and more the day after that. My god those things can eat!
When they stopped on the kale because I put veggie dust on it, they decimated my Mint that was doing so well. 
I have learned, everything has a bit of veggie dust now. it's only sulfur and some other natural compound I forget so not worried about it on the plants and it keeps those green eating machines away.

In suburbia I threw seeds in dirt or in my aeroponic system I made and stuff grew like no tomorrow. When I moved to this rural area I had I ideas of growing enough to do a farmers market once in a while just for the satisfaction of it.
Reality is I can barely get seedlings up and going out here.  It's either too hot and kills them in a day or not hot enough and they get over watered and drowned or something else.  Thought it was me till the next door neighbour with the big greenhouse and the netted patch complained during an over the fence conversation that his veggies were amounting to nothing this year and he didn't know why.
Thats why I set the old fridge up, more of a controlled environment.

Do you have a link for the LED'S?
I really need to put something down the sides of the fridge so they all get light. Haven't got much in it atm so it's OK but when I do add more I'm going to need more than a single light source.

As for the candles, I can't see them warming anything larger than my fridge and If I had LEDS in there, especially with the controller, the heat output from those would be more significant. I think one would need a LOT of those to make any difference to an outside greenhouse even big enough just to walk in. The burn time is a direct relationship to the heat output, more fuel consumed in a shorter time, the better the heat output. That candle while a clever enough idea to be sure, is basically a glorified match with the same heat output. Great for long term lighting but not for heating.  A Tail light globe from a car would have far higher thermal output than that candle.  One could do the maths on the thermodynamics but I'd be guessing its around  3-4W Maximum!
Pint of wax/shortening has less than 6 Kw of energy. He burned that over 120+ hours.  Not a lot of power. First giveaway to me was he picked the jar up. Does not have to be too hot to touch to produce heat but if it's that cool...... Ya.

 Maybe the candle Idea comes from people that think 4 tealights with an upside down flower pot will warm a room?
Placebos cure a lot of medical problems too I spose. Maybe someone should market "Warming Tablets" to these people.  Take one and never be cold for 12 hours.  Active ingredient, 100% chalk.

If you can get the shortening for free, then making a candle with a thicker  wick  or a bit of rope like sash cord would work better. Faster burn, much better heat.  I'd Imagine unless you did them in a bucket you'd be having to do more every day but at least the greenhouse would stay warm.
A small smudge pot burner design running on veg oil I think would be a better alternative. Not something orchard sized but scaled down to where it gave enough heat for the job at hand without being over the top. Last one I did was a 4L saucepan with a 4" Pipe welded in the top and drilled for secondary air and 4x 1" holes in the lid for primary air.
With a 6ft flue that thing would throw enough heat to keep people back 4 ft and still had a jet flame out the top.
With the same 4L saucepan and something like a 1"  flue/ secondary air mix chamber and a 1/2" primary air control that had a bit of metal over the top that could be moved to regulate it, You could tune the thing to do the sort of output needed for a greenhouse.

An electronics Boffin like yourself could probably use a small carburetor off something like a chainsaw  linked to an arduino for primary air control.  Set the " Idle " on the carb to allow enough air to keep the heater just going and link the arduino to a thermostat. 
When the greenhouse cools off, arduino uses a servo to open the carb ( just want the carb for an accurate air metering) allowing more air and greater heat. When it's warm enough,  the carb closes off the air and the thing idles.
All the fuel oil is in the pot. There is NO need to drip feed like you see on a lot of designs. It works just perfect in batch mode.  All you need to do is control the primary air and it burns just fine.  Refill and Light at night  and shut off in the morning. If the servo could be set to hold an idle air setting, It could close the burner off all together when a set temp was reached or exceeded for a time or a CDS sensed it was daytime...... Or leave the thing burning all the time apart from top ups which you could do when lit if you had a cap on a refill port.

Haven't done anything with hydroponics but my aeroponics system made from a plastic drum, a fountain pump and a timer works a treat on Lettuce, rocket, Kale and similar leafy greens.

Bruce S

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Re: Phase Change [heating with solar]
« Reply #33 on: November 13, 2017, 09:10:33 AM »
George65
The candle stuff does just what I need it to do, keep the chill off. No fast burn needed merely nice slow heat. If I want bigger, I'll run to the hobby outlet and get the bigger 3-wick types you can all but cook on.
I agree a bigger wick would work better, we don't always get a complete burn. Since most of this stuff is free/cheap; it'll do until my veggie oil is filtered and we have enough to last through the coldest parts.
Biggest problem? Keeping the candles up high enough so the DOG does lick up the fuel.
 
This is what Toby looks like once he got caught.

Dumbest thing I did was stop veggie oil gathering and filtering.

At the time, I was getting $0.60/US gal for the filtered stuff.

I have the parts to build a drip heater, building these come easy, from my old ARMY days when we heated the GP-Medium tents with diesel heaters and a Jerry can.
 
Here's a link to the LEDs
https://www.aliexpress.com/item/5V-2-5W-USB-Grow-Light-Indoor-Flowering-Vegs-Potted-Plants-Growth-LED-Lights-Lamp-For/32803159235.html
They're only 2.5 watts/ea  , and here's what two look like with a Mylar surrounding.
 
These mess with my eye sight, but the backs are slightly toasty so heat gained for plants; I have a touchless thermometer; I'll get a temp reading on these soon. They're supposed to run at 5V 1A but I have them on a 110Vac to 5Vdc 800mA adapters (makes life easier)


Here's the newest addition to our culinary plate  :) These are yellow tomatoes, I didn't have as many problems with aphids on these as I did the better boys. The heirloom reds didn't have ANY problems with bugs, so go figure.



Here's a recent harvest. The heirlooms are the bigger of the bunch. With frost always looming; we pick them yellow-ish and the Roma/cherry hybird ones green with white bottoms These were completely volunteers that came up close the one of the compost bins.
 
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george65

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Re: Phase Change [heating with solar]
« Reply #34 on: November 13, 2017, 04:55:46 PM »

Thanks Bruce, I'll look those lights up. I didn't realise they were USB. Very economical!

Seeing them that colour reminds me of  couple of Hydroponic shops I have been into.

Started asking them things about different nutrients and they were talking about buds and heads some  levels.  Said I don't have buds or heads they just flower then fruit. Guy is confused and ask what I'm talking about. I say Tomatoes. The penny drops simultaneously and then I ask him, what are YOU talking about?  :0)
Then guy asks why I'd want to use nutrients and lights on tomatoes. I said because I like frigging tomatoes!

Similar thing happened in 2nd shop I went to.
I think growing Pot keeps these guys in business. Most of the other people in there didn't exactly look like they were into growing their own fruit or veggies either. Must have thrown them off having someone come in and actually wanting to grow something to eat not smoke.
Bloody stoners.

The fridge setup is working really well. The Bar light keeps it warmer than I would have thought in there and after only abut a week since I put the last seedlings in they are going nuts. Keeping the door shut helps keep the moisture humidity in too which seems to be doing them well.
I have been using a seaweed based hardware store type fertilizer which is supposed to be added every fortnight or so.  I'm breaking that down to 10% dose and adding it every time I water. Plants seem to be very happy with that.

I have not got any veg oil since I moved and was thinking of collecting at least an IBC's worth over summer and putting it up the back to settle.  Once I get the tractor and the lister set up,  I will be able to burn it again and If I want to do some winter heating it's there too.  Was thinking of putting a heater in the shed as I'm going to extend it and insulate it just to seal the air gaps if nothing else.
In the old days Mate and I would go out on a Sunday morning and collect an IBC full for Bio making.  Miss those collection runs and looking like 2 garbage men sitting at the swank caffe's having a bit of brekky half way through and the weekends of Brewing up huge Bio batches.
Was hard work but fun using all our DIY hatched together system from scrap that worked so well and made great Bio.  Man we made some Bio!

Bruce S

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Re: Phase Change [heating with solar]
« Reply #35 on: November 14, 2017, 06:58:36 AM »
Stoners  :o, yep get those looks too..
Gotta get 'em they live 1/2 the time; "munchies" tell 'em tomatoes are the bees knees when it comes to munchies and they'll hemp you all they can.

From testing different nutrients and learning, I've found a couple things to be most helpful. Epson salts at 1/2 the recommended dosage and coffee grounds that are buried in the coffee filters work for a good jolt for the plants too. 

Basil both [sweet and Thi] love growing in water borne containers. I have so many plants I'm now bringing in some for the office
On a stupid move note: Tomato and Kale do not like being in the same planting area. NOT sure why, will need to stop at Agri-extension or find out via search engines.

ALSO:: I went with the 2.5W size , but have ordered the 5W size this time. I want to check on the heat output of one light versus two. I'll get my touchless thermometer and get readings on the two LED setup soon.
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george65

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Re: Phase Change [heating with solar]
« Reply #36 on: November 14, 2017, 03:26:07 PM »
Epson salts at 1/2 the recommended dosage and coffee grounds that are buried in the coffee filters work for a good jolt for the plants too. 

There are 2 raised garden beds here I planets in. Line of tomatoes in each. Only bed seemed to be doing OK, the other looked real yellow in the leaves and weren't coming on. I thought this may be a Magnesium deficiency so sprinkled a few pinches of epsom salts around each plant and watered it in.
They do seem to recommend a LOT of epsom salts as I was reading on the box but I'm not that game.

A few days later I got the horse manure I had collected from the local Equine park a month or so back and put it through the chipper.
Works brilliant! Instead of getting a clump of straw and then sawdust than a chunk of horse Hockey, it all get blended up into a nice, fine , even powder that's easy to spread around.  I put that on both tomato beds, one which also has corn and beetroot and everything seems to be coming on real well. The sickly tomatoes have gone dark green and are taking off inside of a week. Don't know if it were the salts, the manure or both and don't really care. The end result is great and that's all that matters.

I want to put a tarp in the back of the ute and go down and fill it up with the manure. I'll put it all through the chipper which actually taxes it a lot more than most of the branches I put through it, and make a heap of powder I can put on all the garden beds and lawn.

I think I over did it with the light in the fridge. Went and looked yesterday and my Bigger plants looked like they had burnt off. Don't know If I had the light too close or it was a lack of water. Getting pretty bumed with this.  Been growing Tomatoes since a kid and considered myself bit of a dab hand at them and lets face it, they take no skill to grow but I must have planted 50 and got 10 this season.  Wife is dragging me away on a " Holiday" I do NOT want to go on one bit and am going to be pissed off the whole goddamn time so I expect when I get back I'll have nothing at all because god forbid daughter should water anything for me.

I have a heap of those watering timers and had I had notice of this
holiday" I might have tried to work the things out but they seem complicated just to make them turn the water on and off manually let alone set the damn things.

Mary B

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Re: Phase Change [heating with solar]
« Reply #37 on: November 14, 2017, 04:54:43 PM »
Make sure you wash the chipper out very very well! Manure is corrosive!

Bruce S

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Re: Phase Change [heating with solar]
« Reply #38 on: December 07, 2017, 07:00:10 AM »
Since winter has arrived here, I've been keeping a close eye on the heated areas .
The tomato plants seem to know it's cold out there, the vines have stopped producing flowers.
I'm now down to picking only a few tomatoes now, with the possibility that I might forget to either plug in the LED lights or re-fill the oil based heaters; I pick them green but only once they've begun to turn white on the bottoms.

Here's one of the tasty little ones.
They have a ton of taste and meat inside, I don't hurry the ripening process, merely sit it and the other 4-5 on a east-side window sill.

George65
I took a heat reading of those LED grow lights. pointed right at one of the sides where the light and Aluminum bases shows 100F, with the little cooling fan not running.

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frackers

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Re: Phase Change [heating with solar]
« Reply #39 on: December 07, 2017, 04:24:35 PM »
I'm now down to picking only a few tomatoes now, with the possibility that I might forget to either plug in the LED lights or re-fill the oil based heaters; I pick them green but only once they've begun to turn white on the bottoms.
Here's one of the tasty little ones.
They have a ton of taste and meat inside, I don't hurry the ripening process, merely sit it and the other 4-5 on a east-side window sill.
When my tomato plants get to that stage, I cut them off at ground level and hang them up-side-down, with the tomatoes still attached, in a warmish place and they will ripen on the vine.
They seem to be less prone to rot if ripened like that.
Any green ones left over go to make green tomato chutney with home grown apples, onions and chilli (plus a few spices).

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george65

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Re: Phase Change [heating with solar]
« Reply #40 on: December 07, 2017, 10:54:16 PM »

How are the heaters going? have you measured the in/ out temps to see what effect they are having?
I'd like to know about how many you are running in what size area etc and your thoughts on them.  Why don't you  put the lights on a timer or sensor.
I got in trouble for not having the Xmas lights on when the Mrs came home. Got one of those day/ night sensors, put it in a little box spliced in the middle of a lead and as soon as it starts to get dark, on they come. I remember to put them on without fail now!

Pleased to say between the Daughter and the nephew who volunteer himself to look after the watering, it all survived... even some of the trays with seedlings he filled and were swamped.

Tomatoes are not going great. OK, but not great. The ones in the 2nd bed are growing at a very slow rate for some reason. Bit baffled but I'm thinking that the trees are robbing the soil of all nutrition and goodness.  Already given one of them the sword, now I'm eyeing off some nearby hedge type plants  wondering about them?  Just weird 2 garden beds 2 feet away from one another are producing such different results. I'll load on some more powered manure and epsom salts and see how that goes.  Put some carrots in the same bed so see how they fare as well.

My potted tomato I bought from the other place seems to be dying for reasons I can't figure.  Got a heap of plants ATM but I'm disappointed I'm loosing that one. All the half grown fruit is ripening so I'll have some for the early Christmas lunch this weekend.
beetroot has got huge. Looking forward to enjoying that as well!

Bruce S

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Re: Phase Change [heating with solar]
« Reply #41 on: December 08, 2017, 06:55:50 AM »
When my tomato plants get to that stage, I cut them off at ground level and hang them up-side-down, with the tomatoes still attached, in a warmish place and they will ripen on the vine.
They seem to be less prone to rot if ripened like that.
Any green ones left over go to make green tomato chutney with home grown apples, onions and chilli (plus a few spices).
I hadn't though of cutting the vines . Good one to try.
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Bruce S

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Re: Phase Change [heating with solar]
« Reply #42 on: December 08, 2017, 07:45:48 AM »
george65;
I do have the lights on a timer. On a 06:00 off at 19:00. I found a real nice easy one at a thrift store for $2USD, whereas at a bigbox store they normally go for $10USD.

I got worried last night due to the extreme cold front moving in from Canada got to -8C, so I lit up 6 of these. I am glad it's finally here, misquotes and fruit flies are a pain in my neck. I've found the larger wicks burn faster, but also hotter.
The inside got down to 10C which ain't good for the plants.

Your potted one, can you pull in out of the pot and look at the roots? I'm betting it's smothering down there.  Give it a good rinse if it's got an off smell, fresh rain water then re-pot. Had a 2-year old basil plant do the same, I pulled it out of the pot and stunk up the place with the rotting roots. It did not survive.

I'm still waiting for the veggie oil to settle out, I'm going to merely drop a hurricane lantern wick in one to see if that's a better way to go. This candle burning is a nice way to use up rancid shortening , but ,,, I must be getting old or something.


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Bruce S

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Re: Phase Change [heating with solar]
« Reply #43 on: December 08, 2017, 09:31:01 AM »
George65;
I forgot, to also say. If you have the tomato plant(s) around the Kale, move them . The pretty pics I had of the indoor yellow tomato plant? The very same container had the Kale that got chomped on by the White Moth worms. I was able to get one small fruit off the plant until it simply died.

Seems tomato plants and Kale don't play nice together according to the plant scientists over at our daughter's university.
Really nice people , a bit more paranoid than I am about hydroponic setups, but since they're giving me free advice.  ;D.

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Bruce S
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george65

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Re: Phase Change [heating with solar]
« Reply #44 on: December 08, 2017, 11:09:34 PM »

10oC don't sound too bad to me. I had 3 plants survive 2 years and it sure would have got well below 10oC for at least a couple of months at night. Not saying they liked it but they did survive it.

I'll have a look at the roots of that plant. Not hard to take it out and re-potting it might be worthwhile. Thanks for the tip!

I went up the garden this morning to see how things were doing and check on the nice tomato i was going to pick for lunch tomorrow.
Some mongeral thing has eaten it!
 I don't know what it was , fruit is still half there but whatever ate it sort of gutted it and left a lot of the skin there and took the pulp out. Don't think it was a rabbit but may have been a lizzard. Really annoyed!  Might have to put some sort of trap up there and see what I come up with.
Life in the semi rural area is not working out garden wise how I hoped!

As for your wick in the oil, I tried that years ago and found the same as some other people, for whatever reason the oil does not wick well and just burns the wick down. by all means give it a go though, not much to loose and I'd be interested to see if you find the same thing.  Funny how wax can do it but oil can't.

I also tried some steel wool wicks and that as a bust. Maybe some strands of cotton rag twisted together might work?

For oil, I think your best bet may be a mini updraught burner. Many people call them drip feed burners and that's how they run them but they work just fine as batch burners with the chambers filled with oil and lit. They will burn till the fuel runs out and you can top them up if you want. Sounds like even if you had one doing 1-2KW you would heat your greenhouse just fine.  If you had a pot with say 2- 4L capacity, you could go all night without problem.