All year greenhouse

Acuario · 06-13-12, 02:16 PM

I have been given an evacuated tube solar water heating system and am thinking of how to incorporate it into a climitized greenhouse system.

I'm planning to buy a 13M2 greenhouse so would like to try to get the whole thing built at the same time.

My idea is to use the solar water heater to collect heat during the day and to have it connected to an underfloor heaing system in the greenhouse to maintain the soil temperature overnight and during the morning. The heating panels would be covered with soil in raised beds.

I'm also thinking of using a temperature/humidity sensor coupled to a processor based control system and (if I can work out how to construct them) motorised roof windows. The controller will control the heating/watering/windows to maintain an optimum growing condition.

Has anyone done anything similar to this? Any pointers/suggestions; soil depth/optimum temperature/humidity?

Nigel

Daox · 06-13-12, 02:44 PM

Sounds like it will should work depending how much solar collector area you have and your local climate. At the very least it will increase the growing season.

I'd also suggest at least insulating around the perimeter of the green house, and if you can insulate the bottom of it and then dump soil into the insulated box you've made.

Geo NR Gee · 06-16-12, 11:35 AM

It would be intersting to know how much of a storage tank you would require in order to heat the greenhouse in the coldest winter days.

My friend has a large greenhouse business and grows only part of the year. He said that he needs to always maintain about 70F in order for his plants to grow healthy. He grows strawberries, squash, tomatoes and some other vegtables. He said his major expense is heating.

After I explained about the ground source heat, his interest became apparent and wants to know more. But the idea of using evacuated tube solar heating and storage tanks may be less expensive?

Geo

remint · 06-21-12, 11:17 PM

Quote:

Originally Posted by Daox

I'd also suggest at least insulating around the perimeter of the green house, and if you can insulate the bottom of it and then dump soil into the insulated box you've made.

I've even heard that adding digesting compost in this type of box surrounding the base, would additionally boost internal heat of the greenhouse.

strider3700 · 06-22-12, 01:17 AM

getting greens to survive the winter isn't overly difficult. Getting them to grow through the winter can be hard. They need to warm up during the day to grow. A greenhouse can help with this.

For kicks last winter I planted lettuce, carrots and beats in a front garden where I knew they would be sheltered from the worst of the weather and should survive. The did survive but didn't grow a bit from mid october until late march. I think with a small poly tunnel they'd have kept growing at least another month probably right through.

basjoos · 07-05-12, 10:34 AM

Quote:

Originally Posted by strider3700

getting greens to survive the winter isn't overly difficult. Getting them to grow through the winter can be hard. They need to warm up during the day to grow. A greenhouse can help with this.

For kicks last winter I planted lettuce, carrots and beats in a front garden where I knew they would be sheltered from the worst of the weather and should survive. The did survive but didn't grow a bit from mid october until late march. I think with a small poly tunnel they'd have kept growing at least another month probably right through.

Besides low temps, the other main factor causing limited plant growth in the winter is the short day length. This is why a lot of overwintered veggies that just sit there through Dec and Jan, then start growing from Feb on, despite Feb temps that are just as low as Jan temps. The higher your latitude, the more this is a factor in your plant's growth. At my latitude (34 N), most veggies remain in the doldrums from late Nov through most of Jan, even under cover. The main exceptions to this being lettuce cultivars developed in Europe for winter cropping and many overwintered Chinese crops. Compared with European spinach cultivars, Chinese spinach cultivars are less cold hardy but will keep growing and producing through the shortest winter days where European spinach just sits there. But as the days start to lengthen in Jan-Feb, the Chinese spinach will bolt while the Europeans will start growing nicely before bolting in Apr.

Indyplumber · 09-02-12, 10:34 PM

Saw an article in Mother Earth News (i think) where someone made a greenhouse out of hog panels...very strong and able to withstand snow build-up. I have an old 75 gallon gas water heater and was thinking of DIY on the panel with PEX for the heat exchanger. It would be a drainback system. I also have some small circulator pumps, one for the panel (minimal head pressure) and one for the loop. I suppose I could run just one for the whole thing-though the loop then the panel-but I'm not sure the pumps I have could handle the friction though the loop then the panel w/o burning up.

If I REALLY wanted to do it right, I would also have a PV panel with a small wind turbine backup to power a bank of batteries, which would in turn power some grow lights set up with a photocell and a timer. The timer to turn on the lights at 6AM and off at 8PM and a photocell to turn them off when its daylight enough. (hmmm maybe even enough power to run some 12v pumps).

I'm not sure what temp the ground needs to be to encourage growth though...gotta look into that.

Daox · 06-18-12, 10:15 AM

Our neighbors have two greenhouses that are of fair size (not gigantic) on their 2 acre lot. They're made of two layers of plastic and they blow air between them creating a baloon effect and an air barrier for some insulation value. With this setup and some foam insulation around the perimeter they're able to grow year round. In winter they grow lettuce and spinach which can handle mildly freezing temperatures down to the high teens (degrees F).

remint · 06-22-12, 10:55 PM

Quote:

Originally Posted by Daox

Our neighbors have two greenhouses that are of fair size (not gigantic) on their 2 acre lot. They're made of two layers of plastic and they blow air between them creating a baloon effect and an air barrier for some insulation value. With this setup and some foam insulation around the perimeter they're able to grow year round. In winter they grow lettuce and spinach which can handle mildly freezing temperatures down to the high teens (degrees F).

Low Cost DIY greenhouse design of similar construction:

greenhouse

basjoos · 06-20-12, 10:00 PM

Spinach is cold hardy to around 0F. The cold hardiness of lettuce varies greatly depending on the cultivar, but the cold hardier lettuce cultivars can take down to 5F.

06-13-12, 02:16 PM	#1
Acuario Apprentice EcoRenovator Join Date: May 2011 Location: Tortosa, Spain Posts: 221 Thanks: 2 Thanked 81 Times in 46 Posts	All year greenhouse I have been given an evacuated tube solar water heating system and am thinking of how to incorporate it into a climitized greenhouse system. I'm planning to buy a 13M2 greenhouse so would like to try to get the whole thing built at the same time. My idea is to use the solar water heater to collect heat during the day and to have it connected to an underfloor heaing system in the greenhouse to maintain the soil temperature overnight and during the morning. The heating panels would be covered with soil in raised beds. I'm also thinking of using a temperature/humidity sensor coupled to a processor based control system and (if I can work out how to construct them) motorised roof windows. The controller will control the heating/watering/windows to maintain an optimum growing condition. Has anyone done anything similar to this? Any pointers/suggestions; soil depth/optimum temperature/humidity? Nigel

06-13-12, 02:44 PM	#2
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	Sounds like it will should work depending how much solar collector area you have and your local climate. At the very least it will increase the growing season. I'd also suggest at least insulating around the perimeter of the green house, and if you can insulate the bottom of it and then dump soil into the insulated box you've made. __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

06-18-12, 10:15 AM	#8
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	Our neighbors have two greenhouses that are of fair size (not gigantic) on their 2 acre lot. They're made of two layers of plastic and they blow air between them creating a baloon effect and an air barrier for some insulation value. With this setup and some foam insulation around the perimeter they're able to grow year round. In winter they grow lettuce and spinach which can handle mildly freezing temperatures down to the high teens (degrees F). __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

06-20-12, 10:00 PM	#10
basjoos Helper EcoRenovator Join Date: Apr 2009 Posts: 75 Thanks: 0 Thanked 10 Times in 7 Posts	Spinach is cold hardy to around 0F. The cold hardiness of lettuce varies greatly depending on the cultivar, but the cold hardier lettuce cultivars can take down to 5F. __________________ To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

06-16-12, 11:35 AM	#3
Geo NR Gee Journeyman EcoRenovator Join Date: Jan 2011 Location: Seattle Posts: 326 Thanks: 109 Thanked 23 Times in 18 Posts	It would be intersting to know how much of a storage tank you would require in order to heat the greenhouse in the coldest winter days. My friend has a large greenhouse business and grows only part of the year. He said that he needs to always maintain about 70F in order for his plants to grow healthy. He grows strawberries, squash, tomatoes and some other vegtables. He said his major expense is heating. After I explained about the ground source heat, his interest became apparent and wants to know more. But the idea of using evacuated tube solar heating and storage tanks may be less expensive? Geo

06-22-12, 01:17 AM	#5
strider3700 Master EcoRenovator Join Date: Dec 2008 Location: Vancouver Island BC Posts: 745 Thanks: 23 Thanked 37 Times in 30 Posts	getting greens to survive the winter isn't overly difficult. Getting them to grow through the winter can be hard. They need to warm up during the day to grow. A greenhouse can help with this. For kicks last winter I planted lettuce, carrots and beats in a front garden where I knew they would be sheltered from the worst of the weather and should survive. The did survive but didn't grow a bit from mid october until late march. I think with a small poly tunnel they'd have kept growing at least another month probably right through.

09-02-12, 10:34 PM	#7
Indyplumber Lurking Renovator Join Date: Jan 2011 Location: Indiana Posts: 18 Thanks: 3 Thanked 1 Time in 1 Post	Saw an article in Mother Earth News (i think) where someone made a greenhouse out of hog panels...very strong and able to withstand snow build-up. I have an old 75 gallon gas water heater and was thinking of DIY on the panel with PEX for the heat exchanger. It would be a drainback system. I also have some small circulator pumps, one for the panel (minimal head pressure) and one for the loop. I suppose I could run just one for the whole thing-though the loop then the panel-but I'm not sure the pumps I have could handle the friction though the loop then the panel w/o burning up. If I REALLY wanted to do it right, I would also have a PV panel with a small wind turbine backup to power a bank of batteries, which would in turn power some grow lights set up with a photocell and a timer. The timer to turn on the lights at 6AM and off at 8PM and a photocell to turn them off when its daylight enough. (hmmm maybe even enough power to run some 12v pumps). I'm not sure what temp the ground needs to be to encourage growth though...gotta look into that.