What is the best/worst ways to do supplemental heat in a greenhouse?
Steve
Our local plantsman used hot water. Seemed constant and humidity
friendly. He grew just about everything and valved off and on as
required. Mr Duncan was a officer in the Navy in WW2. Married a German
war bride and had a small farm maybe 20 acres. I'd ask for a doz pulled
plants and get over 20. Get asked in for a bit to eat and a shot too.
Whew I miss them!
<http://www.thomasnet.com/products/boilers-greenhouse-heating-6112809-1.h
tml>
Bill
--
Garden in shade zone 5 S Jersey USA
http://www.youtube.com/watch?v=dBnniua6-oM deals with Sugars
Started your celebration a bit early, didn't you Shelly, or have you
just kept this "heat" goin' since Thanksgiving?
--
"When you give food to the poor, they call you a saint. When you ask why the poor have no food, they call you a communist."
-Archbishop Helder Camara
http://tinyurl.com/o63ruj
http://countercurrents.org/roberts020709.htm
which are the long, fractured URLs below:
http://www.rngr.net/Publications/fnn/2007-winter-forest-nursery-notes-2/
2007-winter-forest-nursery-notes/root-zone-heating-can-save-energy-by-
reducing-needs/file
http://www.hrt.msu.edu/energy/Notebook/pdf/Sec3/Exploring_Underbench_Heat
ing_Systems_by_Bartok.pdf
http://www.umass.edu/umext/floriculture/fact_sheets/greenhouse_mana
gement/jb_root_zone_heat.htm
Sorry, I haven't looked at the links above, you don't get better than
Kay Lancaster, but let me just say that if the flames on this propane
heater come to a blue tip and not just a billowing cloud of flame, there
is no chance, that I can see, that CO would be a problem.
I don't think propane will be a good value. When I ran the numbers
here, electric was cheaper than propane. Bear in mind that electric
heaters are 100% efficient, and propane will not be.
I've got a small "greenhouse" 8' * 8' here that I have been
experimenting with.
My thoughts so far have been to minimize heat loss and to maximize
thermal storage so that night temps don't fall as far. I've had a few
hard freezes and no damage, so far, to my tropicals with no supplemental
heat. I'm thinking of adding some insulation.
You may also think about heat lamps, a little easier to put the heat
where you need it, and less sensitive to drafts as you are heating the
air only indirectly. Hot air goes out with the draft.
Jeff
>
> Steve
>
>
Hmmm ...
Do plants need Oxygen as well as CO2?
The root growth for new plants... I believe needs Oxygen more than CO2.
If one puts a propane barbecue heater inside the greenhouse this may
be bad for the plants because the heat would use up the Oxygen. If I
went with a propane heater it would be a camper/garage style heater in
which the heater is outside and blows the heat inside the greenhouse OR
has an exhaust vent to the outside. Electric mats under the plants are
probably the best way to go. Electric is also nice for the over head
watering systems. Electric can be a problem if the greenhouse is not
near a power source. So therefore... propane.
Cross posted on edible as well.
Enjoy Life ... Dan
--
Garden in Zone 5 South East Michigan.
I don't think many greenhouses are so well sealed that the O2 inside
was much less than that outside.
If I
> went with a propane heater it would be a camper/garage style heater in
> which the heater is outside and blows the heat inside the greenhouse OR
> has an exhaust vent to the outside. Electric mats under the plants are
> probably the best way to go. Electric is also nice for the over head
> watering systems. Electric can be a problem if the greenhouse is not
> near a power source. So therefore... propane.
Perhaps.
A 20lB tank has 360,000 (if burned at 100% efficiency).
If the tank is $20 then at most 18,000 BTU/$
Electric at 10 cents kWh is 32,400 BTU/$
You'd want to buy propane in quantity to make it affordable. Of
course, a propane heater can kick out a lot more heat. But you also
don't have the control and options that you have with electric.
I think we don't know enough about the OPs requirements yet.
YMMV.
Jeff
That's true, bulk propane costs about $2.50/gallon
>Of course, a propane heater can kick out a lot more heat.
That's true. In most locals propane costs less than half of electric.
>But you also don't have the control and options that you have with electric.
That's not true. There are many very sophisticated propane heaters
and most any propane space heater can be thermostatically controlled.
I heat my entire house with propane, I have a propane fired boiler, my
house heats with baseboard hot water, and the same system makes
domestic hot water. Many folks use propane fired forced air systems.
There is no reason that a propane system needs to be fired inside the
greenhouse either. A small propane fired hot water heater can easily
heat a greenhouse for cheap... baseboard hot water radiators would be
better for plants then blowing hot air. If one heats their house with
baseboard hot water and the house is in close proximity to the
greenhouse then the simplist least expensive method it to simply add a
zone for the greenhouse.
> Cross posted on edible as well.
>
> Enjoy Life ... Dan
Dan: I specifically wrote separate articles to the two groups to placate
people who were anal about cross posting. This message was not cross
posted. It was done correctly to avoid people who have filters that
eliminate anything posted to more than one group, and also reach readers of
both groups, where they might not see it if they only read one group.
Hope this helps you comprehend the situation, but I really doubt it.
Are you moderator of this group? Or just want to be?
Steve
But he is worried the power will got out, like it does every year, and
he'll have to chip the ice off his tropicals.
>
> I think we don't know enough about the OPs requirements yet.
>
> YMMV.
>
> Jeff
> >
> > Cross posted on edible as well.
> >
> > Enjoy Life ... Dan
> >
Sounding a little testy Steve. Cabin fever setting in already?
<stupid sig, blogsites and websites snipped for kindness>
Nah. Just don't like people who have more to say about the person than the
topic.
Kinda like you.
plink!
I missed that, that pretty much settles it.
Do we know anything else about his greenhouse?
Had lunch in mine today. 40F outside, 70F inside, until the sky
clouded over!
Jeff
> In article <dgds07-...@news.infowest.com>,
> "Steve B" <desert...@fishmail.net> wrote:
>
> > "Dan L." <doesn...@goesnowhere145.net> wrote
> >
> > > Cross posted on edible as well.
> > >
> > > Enjoy Life ... Dan
> >
> > Dan: I specifically wrote separate articles to the two groups to placate
> > people who were anal about cross posting. This message was not cross
> > posted. It was done correctly to avoid people who have filters that
> > eliminate anything posted to more than one group, and also reach readers of
> > both groups, where they might not see it if they only read one group.
> >
> > Hope this helps you comprehend the situation, but I really doubt it.
> >
> > Are you moderator of this group? Or just want to be?
> >
> > Steve
>
> Sounding a little testy Steve. Cabin fever setting in already?
I wondering about that testiness as well :)
Enjoy Life... Dan
> "Wildbilly" <wldbilly@without_a.net> wrote in message
> news:wldbilly-A2618D...@c-61-68-245-199.per.connect.net.au...
> > In article <dgds07-...@news.infowest.com>,
> > "Steve B" <desert...@fishmail.net> wrote:
> >
> >> "Dan L." <doesn...@goesnowhere145.net> wrote
> >>
> >> > Cross posted on edible as well.
> >> >
> >> > Enjoy Life ... Dan
> >>
> >> Dan: I specifically wrote separate articles to the two groups to placate
> >> people who were anal about cross posting. This message was not cross
> >> posted. It was done correctly to avoid people who have filters that
> >> eliminate anything posted to more than one group, and also reach readers
> >> of
> >> both groups, where they might not see it if they only read one group.
> >>
> >> Hope this helps you comprehend the situation, but I really doubt it.
> >>
> >> Are you moderator of this group? Or just want to be?
> >>
> >> Steve
> >
> > Sounding a little testy Steve. Cabin fever setting in already?
>
> <stupid sig, blogsites and websites snipped for kindness>
>
> Nah. Just don't like people who have more to say about the person than the
> topic.
>
> Kinda like you.
>
> plink!
Yep. Definitely cabin fever, poor bastard;O) Hang on, Steve. Blue skies
will return, you weren't made to be nutso. In the meantime, try not to
break anything, and don't try to bite the cat's head off.
Uh, last thing. Try not to think about a large white bear. It would
probably be enough to put you over the edge.
Come on daylight, and Happy New Year.
--
�When you give food to the poor, they call you a saint. When you ask why the poor have no food, they call you a communist.�
-Archbishop Helder Camara
http://www.jpost.com/servlet/Satellite?cid=1261364551818&pagename=JPost%2FJPArticle%2FShowFull
http://countercurrents.org/roberts020709.htm
I stated what I did, that ticked you off, not what I said about someone
else. There are no criticisms from me about cross posting.
Steve -- what did I say "more about the person than the topic"?
I am curious? What did I say about anyone before your attack on me?
I know the answer --- nothing! Until now, Are you Bi-polar Steve?
Billy, that is how I see the New Year, the days are now getting longer.
Enjoy Life... Dan
What does "best" mean? I tend to think energy effeciency for a
greenhouse, using sunlight and compost to heat the space. Have you
ever seen hot steam coming off a compost pile in the middle of winter?
Depending on your needs, I think you will be hard pressed to heat
only with solar or steaming compost.
Solar requires thermal mass and added insulation.
I've got a string of nights here in the 20's, so I'll see. I've been
adding both thermal mass and insulation. I do have a heat lamp on a
timer... It's my first winter with the "solar cabana", so much remains
to be done.
With that said day time temps have been a delight inside with outside
temps in the the 30's.
No objection to any form of heating, but insulation is often overlooked.
Jeff
I've done similar with 3-4 gallon container plants with homemade
heating jackets, simple 1/4" plywood boxes that house the
container and a heat source. A single 7.5 watt light bulb on a
dimmer is all that I need to keep a pot at an optimal 75 - 80
degrees F even if room temperature drops into the 50s. Plants
given such a cozy set of overshoes thrive, even at 60F air
temperature.
On Tue, 29 Dec 2009 20:01:33 -0500, "Dan L." <doesn...@goesnowhere145.net> wrote:
>Do plants need Oxygen as well as CO2?
Somewhere between zone 5 and 6 tucked along the shore of Lake Michigan
on the council grounds of the Fox, Mascouten, Potawatomi, and Winnebago
Thank you Ingrid!
Even though it was an old posting. I knew the answer to my own question.
What I found was, some posters felt the oxygen factor was insignificant
in the propane heating question.
Somewhere between zone 5 and 6 tucked along the shore of Lake St. Clair
Michigan :)
Enjoy Life... Dan