Greenhouse heating

[bazzaboy]

Right on topic had an email from Harrod Horti this morning with a time-limited offer of 15% reduction on a tough UV stabilised bubble wrap for greenhouses plus easy fittings.... Details at:

Greenhouse Bubble Wrap - Garden Supplies by Harrod Horticultural

[Potstubsdustbins]

What the guy with the tea lights forgot to mention is that (a) he is in the roof of the house therefore the heat rising from below will have a great influence on the heat required to warm the room. and (b) if he is using the brick flue which takes up a large expanse of the room this will also give of heat into the room.

Either that or he is an .......................... Eskimo.

As to calculation the heat required to keep a green house at a given temp standard 4mm glass as a u-value of approximately 6. Calculate the surface area of the glass and using that u-value you can then calculate the heat required.

Potty

[Potstubsdustbins]

Or if like me you are an idle &&^&** you can use one of these or even a free computer program.

Potty

[Duckdad]

Hi polc1410,
you have clearly done your homework on this subject, and i have also dabbled. So far the cheapest way i have achieved GH heating is by Hurricane lamps, (3 for £10 off amazon) and find your local heating oil depot and they will supply you with kerosene/paraffin for about a £1 a litre in 20 litre barrels, the hurricane lamps use about 250ml each for about 12 hours, it keeps the frost out of the GH and polytunnel.

[bravo2zero]

I looked into this a long time back and the all avenues came up to a simple economics brick wall. wind turbines,gas and solar were all too expensive and prone to theft. of the above 3 the option which was most suited to trickle charging was the wind turbine but would produce enough charge to run a small greenhouse heater for 3 hours only and that was thermostatically controlled, it was also the most expensive. ive settled on paraffin and only run it for 6 weeks from first week in march. for heat sinks I do remember a series of programs called ITS NOT EASY BEING GREEN where in one program they filled down a metre into the foundation of a greenhouse with tumbled glass.
hope this helps.

[marcofez]

Hi,
I watched this series the other day, Frost-free Heating the Greenhouse for 4p per day
thought it might help.

[Thelma Sanders]

Which tea lights burn for a long time - tea lights I get here, seem only to last a few hours

[Olorin2001]

good idea but costs of heating are relative to the size of the greenhouse, the temperature outside, location of greenhouse, exposure to wind etc.
What works in the sunny south might not be suitable in the frozen north.

[Bill HH]

I watched a u tube video where a guy made little oil lamps from bottles with metal screw tops, he pierced the tops with a nail and threaded a wick through, filled them up with lamp oil and the flames were very similar to T lights. Apparently you can use cooking oil in them. They were small bottles less than 1/2 litre. i reckon jam jars with screw lids would do just as well. The chances are these would burn a lot longer than T lights and could still be used under a flower pot etc. Maybe you could even use old cooking oil, that would be free.

[Olorin2001]

Was the guy's name Molitov?

[Bill HH]

Was the guy's name Molitov?

I will let you know, I am making one today.

[alldigging]

This bloke shows you how to make little 'oil jars' and these slightly insane candles.

Homemade "TIN CAN" Air Heaters! - Survival/SHTF Air Heater/Stove - Simple "cardboard and wax" Design - YouTube


I suspect the world's fire brigades are sobbing at how many candles are being sold.

Please be careful when playing with fire, candles, oil and matches. etc.

[Bill HH]

From the Torquay Herald Express. "Fireball in poly tunnel, pensioner badly singed"

Actualy it couldnt be further from the truth, I had a jar with cooking oil in, pierced a hole in the lid and passed a piece of 100% cotton string through, as a wick. I then turned it upside down to soak the wick. Then I went for ignition. There was a beatiful flame about twice the size of T light, then the wick just burnt away. I think I need a better wick or different oil, it just didnt seem to travel up said wick. I shall not be beaten. There are lots of heaters on the net but most seem very dangerous, these in bottles with a tiny hole for a wick seem to offer more safety.Maybe parrafin would be best but that aint free. If this works I think it would easily burn for 24 hours.

[veggiechicken]

You may need Candle wicks rather than string.

[Bill HH]

You may need Candle wicks rather than string.

My thinking too, but I thought that wicks are nothing but cotton string. I will try to get some real wicks. More likely cooking oil is just too thick for the wick to draw it up. I could try thinning the oil somehow but i am trying to get a free fuel. The old oil lamps the tudors used were not much more than a bowl of oil with a wick lying in it, will go and google them. maybe I need a whale?