harvesting ice - building an ice house

anyone here build an ice house? I'd like to harvest ice from a nearby creek and store it over Spring/Summer.

Insulate it @ R90 on all six sides.

I had an amish neighbor a few years back, took a look at his icehouse.
12' square, 10' ceiling
18 inches of blown polyurethane foam insulation on all sides (underside of the floor).
Exterior was white.
He had ice all year.

Hey guys, I should have been more clear...

Im going to do this Sepp-style, like his animal shelters. The insulation will be earth (earth floor forum). I'm just not sure how these ice houses work... would I be able to just stack the ice in the room or do I need to dig a hole into the ground and stack them in the hole. The pics I've seen on the net are pretty much useless to me.

I would love to have ice all year round.

Do you think I could store venison in there and be fine?

Venison: try in out for a year with a thermometer before risking a lot of meat.

Insulation around the outside of the ice is important, but getting any melt water out of the system is also important. The old timers used sawdust, which is a good insulator when dry and wicks out the water. It also separates the blocks of ice, which is important when it comes to actually using the stuff.

We don't have a pond or stream nearby, so I've considered just pumping water from the well into buckets regularly. Tried it out and found that 5-gal buckets do not have sufficient draft to allow ice to expand as it freezes. After blowing out a bunch of buckets, I decided that these were not a good mold. I could only freeze 1-2" per day and didn't have enough buckets. If I could freeze the whole bucket at a time I would have been able to make it work.

Another idea I've considered but not tried (moved, new job, etc) is an ice-rink type ice house. Make your ice house with a removable roof. A block of ice that is 4' x 4' x 4' should be enough for an icebox all summer assuming 30% loss. The sides are foam. fill with water, 1-2" at a time. Layer food-safe plastic every 4" or so and place dividers to allow you to remove it blocks at a time.

Another idea is to harvest snow. I don't know how to do this yet... throw the snow in a pile, compact it, cut out blocks to store in an icehouse? Pile it high enough that it compacts on its own? Spray blocks of compacted snow with water to freeze into bricks? I don't know what would work best. Any thoughts?

If you dig a pit, you will need drainage. Without drainage, meltwater will increase the rate of ice loss.

Let's put some science behind the icehouse.
Heat is the enemy. It moves through 3 primary methods: Conduction, Convection, and Radiation.
In an icehouse, the solid mass of ice in an stagnant envelope of air or insulating material has little convection to worry about. If you open the door in the summer, some heat will move in and flow upward, but it is expected that you will shut the door shortly.
Radiation is not much of a concern because you will have insulated the structure and/or the ice.
The primary issue with which you must contend is the conduction of heat from the outside to the inside.
This is where Fourier's Law comes into play: q = k A dT / s
where
q = the quantity of energy conducted through a wall. You want this to be really low.
A = heat transfer area (m2, ft2) This is the size of your ice house or your ice heap
k = thermal conductivity of the material (W/m.K or W/m oC, Btu/(hr oF ft2/ft)) The lower the value, the better the insulating property of the material
dT = temperature difference across the material (K or oC, oF) If it's 90 degrees outside, 20 degrees inside, the dT is 70
s = material thickness (m, ft) Thicker insulation will make your ice last longer

A list of k values for selected materials. 'k' is the Coefficient of Thermal Conductivity. Low k, low heat transfer. In the list, sawdust has a k value of .08, so heat moves through sawdust slowly. Dry earth is on the list with a value of 1.5. You would do well to add material between the earth and the ice.

Now let's look at a practical example. I'll use my old neighbors icehouse, and convert everything to metric.
A: 4 walls 12x10, roof and ceiling 12x12, A=768 sqft =71.3 square meters m^2
k: polyurethane foam, k=.03 W/(m.oC)
dT: 80F summer days, 50F summer nights, 65F degree average outside temp, 20F inside, dT=45F = 7.2 degrees Celcius oC
s: The insulation was sprayed on to a thickness of a foot and a half, s=1.5 ft = .45 meters m
q = k A dT / s
q= (.03 x 71.3 x 7.2)/.45 =W/(m x oC) x m^2 x oC / m
q=34.2 Watts
1 watt = 3.41214163 BTU / hour
q=116.7 BTU per hour

1 BTU is the energy required to raise 1 pound of water by 1 degree F
A pound of ice at 20 degrees, raised to 32 degrees requires 12 BTU. There is about another degree required to change the state from solid to liquid.
In laymans terms, his ice melts at a rate of about 3.5 pounds per hour in the summer, about 10 gallons per day.
To keep ice all year, 275 days of melting, around 2750 gallons of ice will be lost to melting, 370 cubic feet, the top 2.5 feet
If he used sawdust (k=.08 ) instead of polyurethane foam(k=.03), his rate of ice loss would be 27 gallons per day, 1000 cuft, 7 feet over the season from a 10 foot pile of ice. Would not leave him much to work with, but not every day is the heat of summer.

Edited for 2 calculation errors

If you read up on earth shelters/home, you will see that they generally stay warm in the winter.
And about 60F in the summer. At 60F all your ice will melt.
So a earth shelter is good as a refrigerator/root cellar but not as a fridge that stays below the freezing point of water.
So you will not get away from needing manmade insulation, insulation that is rated at R90 or above.

Now if you build a "root cellar" that only opens on the top.
And you filled it with enough ice (10ftx10ftx10ft) then it might last thru a big part of the year.

So build the cellar big and stack alot of ice in it and see how it works out. I would love to hear about it.

Just a quick work check:

unit analysis: q = k(W/mK) *A (m^2) * dT(K) / s(m)
Therefore q has the units of W, not W/mK.

Conversions: 65F - 20F is (18.333C - (-)6.667C) = 25C. Redo your calc to get a heat gain of 68.6W (a Watt is 1 Joule/second)

Phase change: For melting ice, you are only concerned with heating the ice to the melting point and then the latent heat of fusion as the ice melts. Assuming that you are far enough into the year that the ice has warmed up to the melting point, then the rate of ice loss can be easily found:

Latent heat of fusion = 334 J/g

So, taking the above, you will gain 68.6 J/s, divided by 334 J/g, which gives you a ice loss of 0.205 g/s, or 17.8 kg/day x 275 days (converted back to cubic feet) = 187 cubic feet.

Which is pretty close to your calculation, but I just wanted to make sure the calcs were accurate in case others are trying to use them.

The earth serves an excellent barrier to the exterior of the icehouse. Rather than the heat of summer and hot sun exposure on the walls, the earth will maintain a consistent and considerably cooler temperature.

I'm checking, Dave.

Found the problem Dave, corrected above. 2 glaring errors.
Also, rather then get into change of state, I tossed in an extra degree, and most of the figures are rounded to a single decimal, and I did not account for the density of ice compared to water. It's probably close enough for gubmint work.

In the end, not only are ice houses effective, the science supports it. Insulation material can make a considerable difference. Sawdust can get you by, but you may need to stock more ice to get through the year. Better insulation means less work and longer lasting ice.

Ken and Dave -

Thanks for posting all the math. A few comments - As a historian researching ice cellars and ice houses, I've learned that once you dig past a meter or so, the year round soil temperature in central New England is around 50F. So, huge amounts of work do dig a pit or cellar, without huge benefit. Prior to 1805 it was all cellars (Washington at Mount Vernon, Jefferson at White House and Monticello), but after Frederic Tudor commercialized the process of storing and shipping ice it was all in above ground buildings - initially brick or stone, but then wood.

For the cellars, before filling, bottom filled with a foot of gravel and two feet of sawdust on top of that (packed to less then a foot once ice added). Then planked first or ice directly on top of sawdust. As filled, a gap of one foot left between walls and ice, to be filled with packed down sawdust. Or, an inner wood wall built and the space between the wood wall and the outer stone-lined pit wall filled with sawdust.

A common design for small ice houses was a double-walled wood building 10-20 feet wide (all inside dimensions), 10-15 feet high, and 15-30 feet long. If you look up ice house and Tobyhanna, PA, they have an ice house that holds 50-60 tons, and is filled every winter. The gap between the inside and outside walls about one foot, filled with sawdust.

I've seen mention of Amish using expanded polystyrene block 18-24 inches thick (about r=5 per inch). Have to allow for drainage at bottom and venting at top so that any warmer air can escape.

Amish down the road built a new one last year, too late to harvest ice that year. He had to buy ice, I think he spent $600 for the first year. That is cheaper than an electric fridge, especially considering he had a walk-in full of space.

Not deep-freeze, though, so they still had to can most of their meat. But they did not have to can the entire cow in a day.

This year they harvested the ice from their pond, and we only had ice on the ponds for a few weeks total--they just harvested when it was 4" think and forecast for a warm-up.

Nelfson -

George Washington tried snow - it did not work. He had slaves gathering snow, and then pounding it into his cellar to pack it down. Problem is, cannot get close to the density of ice. In subsequent years he sent his slaves out in boats on the Potamac River to bring back pieces of ice.

David , Welcome to permies. Do you think one could use pallets, packed with sawdust or straw, as the walls roof and floors?

Wyo -

From what I've read, it needs a minimum of R30 on sides. top and bottom. However you get there. That could include bales of straw, a double wall filled with wood shavings such as used for animal stalls, a base of wood pellets (like for pellet stoves), etc. Henry David Thoreau describes the winter of 1847 when a huge pile of ice was covered with straw and a tarp - no building - and lasted not just the summer but into the fall and the next winter.

Important point here is minimum volume of ice to make this work. Again, smallest dimensions I've seen for traditional ice houses call for at least 20 tons of ice. I am not saying smaller cannot last through summer, but I am guessing it won't. A much higher R-value would help.

As to why size matters so much, it's about mass versus surface area. A cube of ice three feet on each side has a surface area of 54 square feet and volume of 27 cubic feet, for S/V=2.0. More surface area means faster melting. Take dimensions up to 5x5x5 and its 150 square feet and 125 cubic feet for S/V=1.2 (and ice weight of 3.6 tons). At 10x10x10 the S/V=0.6 and weight = 29 tons.

From historical accounts of big, commercial ice warehouses in Maine, they expected 5% meltage by June (remember, still cold in Maine in June) and 20% by end of August. We are talking buildings with two feet of sawdust between the double walls and outside dimensions of 80 feet wide, 40 feet tall and 300 feet long. They used horse-drawn ice plows to cut the ice six inches deep, pry bars to finish the breaks, and steam-powered conveyor belts. Blocks were roughly 1x2x2 feet and 200 pounds each.

http://www.hemmingjorgensen.com/

This guy did research on the traditional ice houses of Iran. If you want to dig a little deeper maybe something of their construction would be helpful.
webpage

- I found this saved it to my computer and then miss-posted it /// link below :


http://archive.burlingtonfreepress.com/article/20100816/NEWS02/100815019/Essex-project-builds-backyard-passive-freezer

Originally posted in the homestead section ! Big AL