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50 gallon drum?

Excited setting up our first greenhouse!
Delighted to have found this site!
For a 50 gallon drum for heating purposes would a 50 gallon plastic trash can work? If so, would black be best?
Looking at using an aquarium heater to help out as our green house only gets a few hours direct sun
Thanx nuch

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Super Green Thumb
Posts: 5552
Joined: Mon Mar 23, 2009 1:59 pm
Location: TN. 50 years of gardening experience.

Re: 50 gallon drum?

Plastic drum will work to hold water but plastic has very low heat transfer rate so it will heat up very slow from green house heat from the day time sun. 50 gallon metal drums heat very slow too from day time sun heat then the give off very little heat at night. The problem is very low surface area of the 50 gallon barrel does not transfer much heat.

When I built my first green house 42 years ago had no heat storage. 2nd year I had 1 water barrel temperature only warmed up 1 degree all day in the sun. After dark it only lost 1 degree of heat. Then I added 2 more barrels with 3 barrels each barrel heated up 1 degree in the sun then lost 1 degree after dark BTUs are very low not enough to heat green house.

Next I used a 120 volt water sump pump to pump water from barrels through a large car radiator then back to the barrels. Now heat from day sun heats up all 3 water barrels up about 10 degrees and gives off 10 degrees at night still not enough BTU to heat my green house.

Next I used 5 car radiators this heated water up about 50 degrees during the day and give off enough BTUs at night to keep plants from freezing. It took me a lot of experimenting to learn what works. My green house was .004 mil plastic stabled to 2x4 boards. When wind blew hard plastic moved in/out it sucked in cold air and pushed out hot air like a bellows green house could not be heated if wind was blowing.

Next I covered green house with corrugated clear fiberglass sheets this stopped heat lost from wind blowing. Fiberglass only lasted 2 years sunlight destroyed it so I ripped it all off the 3rd year.

I bought a truck load of used sliding glass patio doors and put solar on the roof of my garage. I had copper pipes in all the panels and heat transfer fins to pick up sun heat. Double glass was very good to reduce heat loss. In winter 20°F out side solar panels produces 100°F hot water all day and a very dark over cast cloudy day it produced 70°F water. This produced more heat than green house needed that was about the time I gave up on the green house.

I connected the solar panels to the house it heated the house to 100°F. I put extra insulation in house attic temperature slowly dropped all night about 7 am next morning house was 65°F house heat came on for about 1 hour then solar started making heat and house heat turned off.

Solar panels on the roof leaked I caulked & tared it many times but it still leaked and 6 months of winter rain for 2 years destroyed the roof. I took solar panels down and put them up again 3 times after the 3rd time I repaired the rood and never put solar on the roof again.

You need 1.750" hose or pipe to your 120 volt water pump to all the radiators and back to the barrels to make it heat a green house using day time sun in the green house for heat storage.

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