Butcher Shop Staying Cool in July’s Hot Sun
Without any mechanical refrigeration the butcher shop stays cool in the summer and without any heating it stays warm in the winter. This is due to the extreme insulation (R30 to R120), the six concentric rings of construction and the extreme thermal mass (1.6 million pounds) of stone and concrete used to build the butcher shop.
Although the building is thermally isolated from the earth it behaves more like a natural cave than a typical building because it has enough mass to store winter deep into the summer and summer deep through the winter. The building is a giant thermal flywheel that dampens the fluctuations of our annual temperature cycle.
Our summer high is 86°F while our winter low is -45°F and our annual mean temperature is about 43°F. That last is also about the temperature of our mountain spring water, which makes sense. It makes for a chilly pond for summer swims.
To further enhance the control over the flow of energy the building is build as six concentric shells, like Russian Matryoshka Dolls. Each shell of masonry is separated from the others by thick layers of insulation. The outer warmest area is Admin. The coldest innermost area is the walk-in freezer. Setup as a thermal gradient this helps to control the flow of temperature, humidity and air as well as being integrated into the flow of product and sanitation. The areas that should be coldest naturally tend toward being cold and the areas that should be warmest tend towards being warmer.
Inside the butcher shop now in the end of July it is floating around 57°F in the reefer with a low of 47°F down in the sub-floor of the reefer. This is without doors between most of the shells. I have 4″ inspection ports down through the reefer’s floor, insulation and sub-floor so that I can monitor how the building is performing. Interestingly, as you step up each room the floor increases by one degree, corresponding with the rise in elevation. This indicates stratification which I would expect. The butcher shop does not vary night to day at all but instead remains rock solid through the day-night cycle and varying a little over the annual cycle.
iCutter is running a little warmer than cave at 63°F as I had the door open and it is thermally connected with the inspector’s office (79°F), hall (76°F) and bathroom (74°F) in the Admin section – our warm part of the butcher shop.
All of this is the natural temperature of the shells without any active heating and cooling systems – other than the minor detail mentioned below of equipment which was recently installed. Up until then I got to monitor the temperatures without any equipment adding significant heat – data!
Our cottage, with it’s mere 100,000 lbs of masonry mass is floating at about 76°F today with a low of 66°F – this is with the windows open while the butcher shop is closed other than it’s air exchange ventilation system and our occasionally opening the doors. That is a 10°F variance in the air temperature over the day to night cycle for the cottage. The masonry itself varies less. The mass of the cottage is a lot smaller than the butcher shop, and the insulation is a lot less, so the cottage sees more fluctuation but far less than in the old farmhouse which is a wooden frame building that basically follows the outdoor temperatures.
Speaking of which, outdoors it is 83°F today during the day, dropping to 58°F at night. With a 23°F daily variance that’s a lot different than either the cottage or butcher shop.
This year we installed and began using the 3Ø Converter, the Fricon super fridge (27°F) and the SoLow super freezer (-121°F) along with the inspector’s desk (send your postcards, coins and stamps from around the world!) in the office. All of these, except the desk, generate some heat so the inspector’s office is a toasty 79°F right now.
This boost in heat was because we used the SoLow a lot in the month of July. It’s an amazingly efficient freezer which only uses about $2.62 of electricity to cool 50 lbs of pork to -121°F and then costs along for about 16¢ per hour tops. Given how powerful it is I had expected it to use a lot more energy. We put nine whole hogs and seven roaster pigs plus a lot of smoked meat through the SoLow to flash freeze for customers. That’s a lot of BTUs that the two stage compressors pulled out of the meat and dumped into the office.
Interestingly, even with all of these pieces of equipment generating heat in the office it is still cooler than the outdoors during the day. In the winter the inspector will appreciate that extra boost of heat when it is -25°F outdoors.
One improvement I’ll be making in August is to adjust the office ventilation system so I can move the air out from the ceiling faster which will drop the temperature in there so the freezers can operate a little more efficiently. But that is something I’m saving for after startup since right now I’m working on finishing up the HACCP plans.
Energy consumption is the second largest cost of running a butcher shop – following the cost of labor. Cooling is the majority of that followed by heating of spaces and water. Once I install the passive coolth fluid tanks in the Coolth Attic my thermal performance calculations suggest that the butcher shop will be able to maintain the proper temperatures for each of the shells naturally through 46 weeks of summer based on a two to four week cooling cycle each winter. Since winter is a lot longer than that I’ll be fully charging the thermal coolth batteries every year with ease.
On the flip side for heating water I plan to eventually put in solar hot water. I have designed the building with conduit in place for solar hot water capabilities. We also heat our water off of a heat pump that will chill and dehumidify the iCutter room. There is another heat recover water tank which will grab heat off the future mechanical refrigeration systems to preheat our water from it’s chilly 45°F mountain spring temperatures.
We will have mechanical refrigeration but there won’t be any need for artificial heating. The refrigeration units heat will be dumped into the thermal mass of the Admin to warm the inspector’s toes through PEX pipes already installed in the floor pour under the office and bathroom. The heat pump uses a water based condenser for high efficiency on the refrigeration system. Later we will put additional PEX in the floor of the Abattoir when we finish that off which gives us more thermal mass for dumping heat. This way instead of wastefully dumping heat out to the environment to cool the reefers we’ll simply move the heat from where it isn’t needed to where it is appreciated.
Why have any mechanical refrigeration you might ask? After all, mechanical refrigeration systems cost a lot of money, require electricity, maintenance and space…
Well, there are two issues.
1) I would like to have our freezers run deep, far colder than I can achieve with the coolth tanks in the attic storing winter. The winter cold lets me store about -20°F. Blast freezers benefit from much colder temperatures. When we freeze meat I like to do it very fast using a flash freezer creating micro crystals for the highest possible quality that is just like fresh. The ultra deep freezing also lets us avoid using expensive dry ice ($2.50/lb at -109°F) since our freezers can go colder than dry ice and actually take the meat all the way down to -121°F whereas dry ice can only economically achieve about -60°F. That simplifies shipping and reduces the costs while improving quality.
2) Each week we will be bringing in one to two tons of hot pork at 103°F that needs to quickly drop to below 41°F. Moving that much heat, that fast, is a big challenge. It’s a lot of BTUs to transfer. It takes energy to move energy fast. I can just barely do the thermodynamics required for USDA inspection using the Coolth Attic. Having the extra power of mechanical refrigeration makes it easy.
As long as we don’t have an apocalypse I’ll use the technology of water cooled high efficiency heat pump mechanical refrigeration to boost my natural systems and make the job easier. In the unlikely event of zombies, well, at that point USDA inspection will not be an issue but we’ll still have our backup natural cooling systems. It’s the best of both worlds.
Outdoors: 83°F/58°F Sunny
Tiny Cottage: 76°F/66°F
Daily Spark: It is immoral to transfer the suffering from baby animals to baby peas and carrots just because one feels animals are cuter than plants. The reality is that our brains are hardwired to perceive this cuteness. It is an -ism that biases people without their even being aware of it. The reality is dietary choices have nothing to do with morality.
Walter Jeffries Tinker, Tailor… A bit eclectic & a tad eccentric, polymath, quantum mechanic & Farmer. Also lucky at cards.
Loving this butcher shop. I’m an engineer so the detailed thought and design that’s clearly gone into this is excellent.
One thing I want to ask, costs. How would this compare with a more conventional structure that relies on normal (read huge) energy inputs?
I don’t need convincing, but I want to show this to friends and I know that this will be their first question.
Basically we spent about $56K on concrete and about $120K or so on other materials. There is about $30K in equipment. There is no labor cost to us since we did all of the construction in our own time and I did all of the engineering and architecture. That is a rough accounting of costs of construction at about $206K for the building. Sometime I’ll do a detailed cost breakdown.
This is roughly a 40’x40′ building two stories tall so about $64/sq-ft. The cost of construction is less than what I have read about for similar buildings but on the other hand we took a lot longer to do it and that cost does not include land, site prep, labor, engineering, architect, consultants, permitting specialists, electricians, plumbers, etc since we do all that work ourselves. That is just a a materials cost. Typical cost of building a facility our size is about $1.5 million but that includes all those other things as well.
Typical time to bring a project to completion is about seven to ten years with about two to four years of construction time for the projects I’ve read about. That puts us in range on the longer end at about eight years for our entire project from conception and about five years for construction. We built ours in our spare time as we had the money so that meant it took a little longer.
Short answer: The specialized way that we built did not increase the cost of construction because the materials costs are low and we did the design and implementation work ourselves.
Walter you say there is no cost for your labor but your time is money. Time spent doing construction is lost opportunity. Time spent doing butchering is time you could have been farming raising more pigs.
That is like saying you must do cost accounting when you are reading a book for pleasure or watching a movie, going to a dance, taking a walk on the beach. The reality is when doing cost accounting I do not include our time when I’m totally up the outside costs of construction. We did not pay out money for labor. We invested our time in our project. There was no cost overhead. Besides, it keeps us off the streets and out of trouble. Imagine what mischief I might get into if I didn’t have things up here on the mountain to keep me busy…
Likewise, in fact even more so, when we’re doing the processing the labor cost is again our own and actually saves us time. Currently we spend about 56 hours a week on things related to the hired processing. This can vary greatly week to week depending on what is ordered and does not include deliveries. Doing it here will eventually save a lot of driving time, inspecting each and every meat package (a task that will become part of our process rather than add-on), sorting orders (again like the above), moving things between freezers and coolers, etc. When we are doing the processing here all of that time is freed up to do it so until we use that budget of 56 hours a week we’re working on free time. We can cut a lot of meat in 56 hours.
Then there is the issue that when we do it we make sure it is done right and exactly to our specifications. This is critical when doing construction, especially novel construction. If someone else build our butcher shop it would not be anywhere near as good as it is. What is also not immediately apparent is the building can function as many other things – it has possibilities, potentials built in that are not revealed such that it could be used for other things. Because I designed it, did the engineering, architecture, construction and all the tasks we have a building that is a complete integrated system rather than standard units stuck together as with normal stick construction.
Then there is the sheer entertainment value. Other people like to race cars, go to the horse track, take in the opera, view a movie, etc. I like to solve interesting problems and dance. I like to create things.
“Imagine what mischief I might get into if I didn’t have things up here on the mountain to keep me busy”
….like maybe buying the OTHER side of the mountain perhaps…. ??? :-)
This is so awesome!
I wish I could get a fluid cooled refrigerator or freezer for home use. We have a ductless mini-split HVAC (although I suppose it’s not doing a lot of V-ventilation as the communication from outside to inside is fluid in insulated pipes) system that is more efficient for the use of fluid to carry heat or coolth. It’s got a heat pump outside that looks like a typical air conditioner, plus two units that sit up on the walls to transform the fluid temp into warm or cold air. It’s been a life saver during this freakishly long heat wave we are having here in the normally cooler Pacific Northwest.
But, our kitchen is being warmed by the air-cooled refrigerator, and the garage is being warmed by the air-cooled freezer, which has to work harder because it’s in a not-well-insulated space on the south side of the house. In the future there should be a market for integrated heating and cooling systems for homes, ideally utilizing geothermal wells, that includes food storage.
Awesome that things are put together and you are getting inspections!
typo: We put nine whole whole
Guessing whole hogs?
I’ve always wondered how the Coolth attic will work, I’m waiting for a more detailed article someday :) I’d like to build something similar into my house but we’ll see, earth air tubes might do enough for just cooling ourselves.
If you don’t mind a preview… how do you deal with water expansion when freezing?
Fixed! Thanks for catching that. I always appreciate the extra eyes on my late night typing efforts. :)
How I’ll do the full scale tanks to prevent thermal expansion damage remains to be seen. Curves and elastic materials have all helped in smaller scales. It will be a few years before we build out the big one.
Is humidity/condensation an issue at all?
So far no. I designed it to not have problems with condensation. But we all know the saying about theory meeting reality… So far so good. My math says we should stay fine.
you are light years ahead of me when it comes to engineering, technology, construction, electronics, plumbing and such. I sure do like to try to comprehend it all — and it is good for this old brain. Bring it on! : )
Walter I bet you amke a lot of farmers jealous with all that you have accomplished. I hear some whine about regulations and costs and difficulties but I see you and your family fixing things doing things making things work. You are truly inspirational and I thank you for all that you have shared! It has been facinating to watch your progress on not just your butcher shop but all of your family projects.
How much do you expect to save on energy?
The savings will increase as we do more things in the butcher shop (e.g., first meat cutting a.k.a. butchering, then other things up to full processing). I expect we’ll save about $75,000 to $150,000 in initial equipment setup for refrigeration and about $30,000 to eventually $52,000 or even twice that in future energy costs per year. By investing a little extra thinking time and careful design now the building will pay back many times as well as keeping our carbon footprint low. It also means that we don’t need to have a big generator to keep refrigeration running in the event of a power outage (frequent here) which saves in the generator costs ($35K), maintenance, fuel, noise, etc and even more importantly preserves product automatically through power outages due to the building’s shells high thermal mass and insulation. Until one has lived in a high thermal mass very well insulated structure it is hard to appreciate just how significant the savings are.
Walter I know youv designed this so well as a butcher shop but what if you wanted to do something else with the space in the future? Can it be used for other things?
Sure, the butcher shop could be easily reconfigured to be used for a wide variety of food preparation and processing functions such as cheese making with caves, chocolate making, a dairy, catering, a restaurant, a store, etc. I built everything to code and beyond and during the construction project we had inspectors out here to check things – they loved how we do everything – so it can be used for anything. It could also be used for many other types of businesses.
Additionally the building can get reconfigured to be a home if we wanted. It would be super energy efficient and spacious with lots of big windows. There are places where windows and doors are designed to go should we ever want to do that – Currently they’re covered over and hidden away. All the arched ceilings would make for a very beautiful home and full of light. I carefully designed the building so it can change function if we ever want to do that.
There are options for the future of the building no matter what we want to do with it. I suspect we’ll keep it as a butcher shop for many centuries. People need to eat and meat is something delicious and nutritious that we can easily produce from our mountain pastures with little to no inputs from far away. We’ll see. Check back in 2516. :)
Cool (ha) as always Walter. I would be interested to see you add some of the shop temps up on your posts, as you do with outdoors and “tiny house” already.
Can you elaborate more on how long it takes for the blast freezer to get product down from I-just-put-it-in to -121? Just wondering since I don’t have a blast freezer handy myself. :-)
Wish I had a cooolth attic myself, I will just have to throw more insulation in my attic instead….
I’ve been logging lots of data on freezing and thawing times and will report on that at some point.
Walter,
Would you care to give a five year update on the building?
Also have you taken the opportunity to work on the greenhouse? For many years infrastructure improvements were a major part of Sugar Mtn Farm blog.
Over the last few years I’ve had to deal with some people induced problems including but not limited to ex-employees who did extensive sabotage & destruction of equipment, people who stole livestock, cutting of my fences releasing pigs, dealing with the cretins in the town government who then blamed and fined me for the pigs being loose which is akin to you being charged with armed robbery if someone steals your car and uses it as the get away vehicle in a bank robbery. On top of that came the pandemic. This has slowed down both my posting of articles and infrastructure projects. This year I am working on several infrastructure projects and I’ll be writing about those in the future. Keep an eye on this space…