Hay Boxes or Fireless Cookers

Illustration from The Fireless Cook Book

Mrs. Homegrown here:

Jessica from Holland sent us a letter recently praising our work, but very, very gently scolding us not including the hay box, a groovy old energy saving technology, in our book. We do stand corrected! And her enthusiasm for hay boxes has reignited our interest, too.

We actually considered hay boxes for Making It, but didn’t end up building one for a variety of reasons, including just plain running out of time. But I have to admit one of the primary reasons was that natural gas here is really inexpensive, so the cost savings of starting and finishing a pot of soup on the stove, vs. starting a pot of soup on the stove and finishing it in a box, just wasn’t compelling enough for me to make a lifestyle change. This is a silly excuse–water is also inexpensive here, but I’m obsessed about saving that resource. I guess a lot of what we choose to do just comes down to our various quirks and passions.

I’m thankful to Jessica for reminding me of the hay box. I believe that my New Year’s resolution will be to meditate on the sources and real costs (in terms of the environment, human health, etc.) of gas and electricity, and work on new ways to conserve energy. The hay box, or fireless cooker, may be one of these strategies.

What the heck is a hay box?

Sorry if I’m leaving some of you out of the loop. A hay box aka fireless cooker is a very old fuel saving technology, which perhaps has its origins in Scandinavia.  It is simply an insulated box that you put a hot pot of food into, and leave it all day (or all night) to finish cooking. It’s the forerunner of the crockpot.

This cooking technique isn’t limited to hay boxes. The same concept is used by people who put oats and boiling water into a Thermos at bedtime and enjoy the finished oatmeal in the morning, or by campers who wrap their sleeping bags around a cooking pot so they’ll have hot food when they get back to camp.

As far as I can tell, no one is selling fireless cookers made in the old style, but they are quite easily fabricated at home–or improvised in emergencies. However, if you are in a buying mood, a very similar technology exists in something called thermal cookware. These are essentially giant Thermoses–I’m including a link to a random example of one on Amazon here.

Why would you want to build a fireless cooker?

  • To save time at the stove
  • To have food ready when you get up, or come home from work
  • To save energy, because you’re a do-gooder.
  • To save energy, because energy is expensive/unreliable where you live.
  • To learn this technology well so you’ll know how to use it in case of emergencies. (A fireless cooker combined with something that can boil water, like a camp stove or a rocket stove, would be a great combo for any emergency, long or short.)

Okay, so how do you build one?

It’s really simple. You’re just insulating a pot. There are many ways to do it, including simply bundling the pot up in a bunch of quilts. But if you’re going to do this regularly, you probably want a more stable system than that. You’ll want to build a box.

First, though, you should probably start with your pot and build from there. This technique works best when the pot is full, so you’ll want to choose a soup pot/dutch oven sort of pot that is the right size for you and your family. It should have a lid, obviously, and should be made of something can come and go off the stove top–i.e. no ceramic.

 Once you’ve chosen your pot, you’ll need a box to keep it in. This box should allow enough space for at least 4″ of insulation all around your pot. (We’ll talk about the insulation next.) So the pot height/pot width plus at least 8″= the minimum dimensions of your box.

The cooker could be anything sturdy with a lid, but the tighter built, the better. A big cooler would work great. I’ve just had a crazy inspiration that one of those newfangled ottomans that are hollow inside for stashing away your junk when company comes would also work nicely!

You can make a “two holer” if you want to have the ability to cook more than one dish at a time. In that case you might be able to build one in a hall bench or a big toy chest or trunk. If you can’t scavenge anything, you could build a wooden box with a hinged lid. A well-insulated, box-style solar oven can do double duty as a fireless cooker, too. Whatever you choose, the box should have a lid that either latches or can be weighed down so it closes securely.

If your box is not built pretty much airtight–say it’s pieced together out of wood–you should seal it up before you insulate it. In old manuals they recommend gluing a layer of  paper all over the interior. You might choose to use tin foil or a Mylar space blanket. A space blanket would help reflect heat no matter what your box is made of.

Then you need to choose an insulating material.

Early 20th century options, as per old books:

  • Hay or straw, cut fine
  • Sawdust
  • Wool (they mention this is the best material)
  • Southern moss
  • Ground cork (it seems fruit used to be shipped in this!)
  • Softwood shavings (“excelsior”)

Contemporary recycled options:

  • Styrofoam or foam. Carving a pot-shaped hole into a block that fit your chest would be the best, but scraps could work, too.
  • Shredded paper. At last, something to do with all those bills!
  • Cotton or polyester batting taken from old pillows or quilts. 
  • Wool in the form of cast off sweaters and blankets, perhaps shredded?
  • This might sound nuts, but if you cut down a bunch of weeds, let them dry and chop them up, they would work as well as hay. Straw has that nice hollow stem construction which probably holds heat better than hay, but some weeds have the same sort of stems.
  • Note: I’d discourage using fiberglass insulation for safety reasons. It’s nasty to work with and you don’t want to risk any of it getting in your food.

    Fill the box up all the way with insulation. The box should be filled to the top, but the material shouldn’t be packed so tightly that there’s no airspace. Tiny air pockets are where the magic happens.

    Next, make a permanent nest for your pot in the box by hollowing out a pot-shaped hole in the insulation material. Line that hole, as well as the top surface of the insulation, with a one big piece of fabric. Secure that fabric to around the edges of the box with staples or something. That will allow you to lift the pot in and out easily and will also keep bits of insulation out of your food.

    The final insulation step is to make or find a cushion sized to fill all the empty space in the box from the top of your pot to the closed lid. It should be fat enough that you have to use a little pressure to close the lid. There should be no open space at the top of the box. And again, the lid must latch or otherwise secure tightly. In the image at the top you can see the two cushions that come with that set up.

    It’s often easier to understand something just by looking at pictures. If you do an image search for hay box, you’ll see lots of them, many improvised quickly. Whereas searching fireless cooker brings up more antique images.

    A fireless cooker from a 19th century German catalog, image courtesy Wikimedia.

    Cooking with the Hay Box

    Okay, this is all very theoretical for me because I haven’t done it yet, but this is what I know, and I hope those with experience will comment to help us newbies out.

    The cooker is perfect for anything you’d associate with a crockpot, like pot roasts and other stewed meats, soups and stews and chile, bean dishes and also hot cereals, polenta, whole grains and rice.

    First, it’s pretty much impossible to offer up exact cooking times. It’s going to vary by both quantity of food and the construction of your box. In short, you’re going to have to play with it.

    But the gist of it is that you start your cooking on the stove. If, for instance, you’re doing an initial saute, you’d do that first, then you’d add all your ingredients and liquids and bring it up to a simmer (for how long may vary by recipe–the old cook book I’m consulting most often recommends 10 minutes boiling on the stove for meaty dishes, but if I suspect for non-meat things you could just bring it to a boil and then take it off immediately) then move it to the box to finish cooking. A good box should hold heat for 8 hours. The actual cook time will be less–how much less will vary by dish. But it will not burn or overcook and it will keep warm until you’re ready to eat.

    I’ve heard that in general you would use less water than with stove top cooking because there’s no evaporation.
     
    Here’s some of Jessica’s tips:

    Suggestion: put the beans/lentils/wheat/rice/peas in a thermos flask together with the absorbable amount of boiling water/stock. Do this in the morning. In the evening you have a thermos with still warm and well-cooked food. With just a few seconds of boiling water. Think of the hours per month that you can turn off the stove and still have warm, cooked food!
     …

    It works fine with other things as well:
    Eggs: put pan with eggs and boiling water in, take out of hay chest after 10 minutes (or more, or less, depending on your experience.
    Vegetables: take out of hay chest after 110 to 125% of ordinary cooking time. Experiment! Don’t use a lot of water.
    Stock… why not?


    It even works with things like meat balls and chicken wings. Have the meat on high fire until the outside develops the right crust or color, then keep in hay chest for xx time until inside is ‘done’,

    Mr. Google can lead you to various resources on this technology, but my favorite resource so far is this old book: The Fireless Cook Book by Margaret Mitchell (1909), which is actually both a construction manual and a cookbook–a wonderful crusty old cookbook with recipes for things like Mock Turtle Soup. You can read it online at Archive.org, or download a pdf or even as an e-reader file–for free!

    Do you have any recipes, tips or techniques to share? Please do!

    An obligatory nanny-state warning: If food drops below 140F (60C) for an hour or more, bad bacteria can move in. You might want to take the temperature of your food when you pull it out of the box and see where it is. If it has dropped below that temperature, put it on the stove and rewarm it to at least 165F(74C).

    CoEvolution Quarterly Online

    While hunting down old appropriate technology resources on the Internet, I was delighted to find the winter 1978 issue of CoEvolution Quarterly, put out by the folks behind the Whole Earth Catalog. This issue of CoEvolution profiled Robert Kourik (which CoEvolution spells “Kourick”) who practiced permaculture before Bill Mollison gave it a name:

    [Kourick] is developing methods of growing edible and ornamental plants together for maximum beauty, minimum upkeep, and a self-sustaining yield of food.

    He does it by concentrating on growing perennials that do not need to be replanted each year and annuals that reseed themselves spontaneously. He uses ground cover plants that fertilize other plants, such as the beautiful pastel-flowering lupin which puts nitrogen in the soil. . . Kourick’s goal is to develop what he calls a “self-reliant” garden that produces all of the nutritional needs of each plant. “The gardener,” he says, “can then supply his own nutritional needs by adapting his diet to the garden’s produce.”

    Amen is all I can say to that. A garden that requires fewer inputs is exactly what I’m working on right now.

    In the same article Kourik mentions incorporating fruit trees, kept pruned small, into his gardens,

    Robert Kourick believes that tree crops can be a mainstay of any garden, and he has discovered a plant breeder in Modesto, whom he calls the “new” Luther Burbank. This man is Floyd Zaeger [I think that should be "Zaiger"] who has developed genetic dwarf fruit trees that are strong on adaptive qualities and perfect for Kourick’s garden.

    Floyd Zaiger, incidentally, is the person who developed several of the fruit varieties I mentioned in yesterday’s blog post including the pluot, the aprium and the necta-plum. He developed these varieties through a herculean breeding program involving hand pollinating something like 150,000 trees.

    Robert Kourik went on to write an excellent series of books, Drip Irrigation for Every Landscape, Roots Demystified, and Designing and Maintaining Your Edible Landscape Naturally

    You can read CoEvolution Quarterly and the Whole Earth Catalog for free on the Interwebs at wholeearth.com or download individual pdfs for $2. One of these days I’ll put up a separate page of links to more free appropriate tech and prepping resources when I get the time.

    Netafim Tiran, a Greywater Dripline

    In a lecture I heard recently, Leigh Jerrard of the Greywater Corp mentioned an intriguing product from Australia: a dripline compatible with greywater. Now, if you tried to push gunky greywater through conventional dripline it would clog in seconds. According to the manufacturer, Netafim Tiran Greywater Dripline gets around this problem because,

    Each dripper has its own mini filter. When a contaminant attempts to enter the emmitter, it is rejected by the emitter and simply remains in the tube. The irrigation system should be flushed once a year, however anecdotal evidence indicates that flushing may only be required every 5 years.

    100 meters of Netafim costs 100 Australian dollars excluding tax, or about .30 USD a foot. Not a bad price if it performs as advertised. Some quick Googling failed to turn up a US distributor. Root Simple reader Rachel wrote to point out Netafim’s distributor locatoer: http://www.netafimusa.com/wastewater/support/locator.

    To use Netafim you need to add a filter as you do with every drip system. I could see this product working nicely with Art Ludwig’s Laundry to Landscape system.

    If any of you have worked with Netafim, leave a comment.

    SunCalc: A Sun Trajectory Calculator

    In attempting to figure out how to align a garden path with the sunrise of the summer soltice (that’s the way we roll at the the Root Simple compound), I came across a neat Google Maps hack: SunCalc, the creation of Vladimir Agafonkin.

    According to the description on the site,

    SunCalc is a little app that shows sun movement and sunlight phases during the given day at the given location.

    You can see sun positions at sunrise (yellow), specified time (orange) and sunset (red). The thin orange curve is the current sun trajectory, and the yellow area around is the variation of sun trajectories during the year. The closer a point is to the center, the higher is the sun above the horizon. The colors on the time slider above show sunlight coverage during the day.

    I can see SunCalc being useful for laying out a garden, window and solar panel placement, evaluating potential real estate, or for planning your own personal Stonehenge.

    End of Summer Photos

    I’ve got a backlog of random photos that, somehow, never made it into full blown blog posts. Here’s some of those pics starting with our modest passion fruit harvest. Beautiful flowers and tasty fruit.

    Kelly accidentally planted some potatoes amongst her sweet potato patch. We got a few potatoes and some pretty potato flowers.

    My friends Gloria and Steve, who own a small herd of goats, did a goat milk tasting at the Institute of Domestic Technology comparing their backyard milk against a couple of store bought goat milks and some cow milk. Guess what? Fresh goat milk from the backyard is delicious and does not taste “goaty”. Store bought goat milk just doesn’t compare, though the Summer Hill brand at Trader Joes is passable.

    Lastly, two of my favorite things: cats and corded telephones. 

    Best wishes for a happy fall for all Root Simple readers.

    So-So Tomatoes Become Excellent When Dried

    As we reported earlier, we weren’t thrilled with our cherry tomato choice this summer. They were just plain dull. They were also rather large for a cherry, more like mini-plum tomatoes, which made them awkward for salads. But they were healthy plants, and very, very prolific. In situations like this it is good to remember that tomatoes which don’t taste good off the bush often cook or dry well. The ratio of skin and seeds to pulp in these tomatoes made them a bad candidate for sauce, so we’ve been drying them.

    And man, are they good dried. Like tomato candy. It’s very hard not to snack on them, but I’m trying to save them for the depths of winter, when I really miss tomatoes.

    We have maybe a couple of quarts of them now. Several years ago we had an absolute disaster involving a pantry moth, its many offspring, and one big jar of dried tomatoes. For this reason I’m storing the dried tomatoes in a series of small jars, to offset the risk. Another good tip for fending off moths is to freeze any food stuff which you suspect might be at risk for 4 days to kill moths and their larvae.

    How did we dry our tomatoes, you ask? Usually we use our homemade solar dehydrator, but this year we’ve got a friend’s electric dehydrator on loan. It seemed wicked to run the thing day and night, but it dries a lot faster, and with less work overall, than our solar set-up. (Oh, the wonders of Modern Living!) The one thing I did not like, though, was the constant noise. The dehydrator sounds a little like a running microwave, not loud, but persistent. I was always half-consciously expecting to hear the microwave “ding!” at any moment.

    So, while the electric dehydrator let us process this crop of tomatoes in record time, I don’t think we’re going to ever buy one ourselves. Old Betsy, the wonky wooden dehydrator, suits us well enough.

    CooKit Solar Cooker Made Out of Wood

    The nice folks at Solar Cookers International gave us permission to reprint plans for their CooKit solar cooker in our book Making It. You can access those plans, as well as many other solar cooker projects, for free, on their website here.

    I’ve made CooKits out of cardboard and aluminum foil a couple of times. One problem is that I eventually bang up the cardboard and I’ve got to make a new one. This summer I had a lot of  1/4 inch plywood leftover from fixing up Mrs. Homegrown’s writin’ shed. Rather than send that plywood to the dump I decided to make a more permanent CooKit.

    I blew up the CooKit pdf from the SCI website using Adobe Illustrator.  I did a tiled printout and taped the pieces together to create a life sized pattern. I used this pattern to cut out the plywood pieces.

    I spray glued the aluminum foil to the plywood. Next, I drilled holes in all the pieces and inserted twist ties to, essentially, create little hinges so that I could fold up the CooKit when not in use.

    The plywood CooKit folds much better than my cardboard versions did.

    This type of “panel” solar cooker works best for things like polenta and rice. Now I’ve got a convenient folding panel cooker for backyard use and camping trips.

    Emergency water storage

    We’re finally ready for The Big One. In terms of emergency preparedness, we were pretty well set in terms of food, light, fuel, etc., but we didn’t have much water. Just some jugs, a rain barrel that’s empty most of the year, and the water in our hot water tank. This lack made me nervous, so we finally did took the bull by the horns–or the bung hole…

     How much water should you store? 

    1 gallon of water per person per day. This is the minimal amount necessary for drinking, cooking and very basic hygiene. If you live somewhere it can get beastly hot, factor in extra water for drinking. In scorching temps you’ll need a gallon per person a day just for hydration.

    Expect you’ll need at least a two week supply. That’s a minimum 14 gallons per household member. Then be sure to add extra water for pets and livestock. When we considered all of that, it seemed like a 55 gallon drum was not too much for the two of us and our pets. Ideally, we’d store more. It doesn’t rain here 3/4 of the year, and there isn’t any natural water source nearby. A second drum might be in our future.

    What we’re using:

    We shelled out the money for a brand new, food grade 55 gallon drum. The reason we didn’t go with a much cheaper used food grade drum is because some food stuffs leave behind residues which is impossible to clean from the drum. These might just manifest as off odors that make the water smell and taste bad, or they might even contain tiny traces of food will lead to bacterial growth during long term storage. For example, it is impossible to clean away traces of dairy, no matter how hard you scrub. It seemed better to just pay the extra money than to worry about it.

    I don’t like plastic much, but short of buidling a concrete cistern or something like that, the only other similar option would be to buy a stainless steel drum. I’d much prefer to do so, but new ones priced out in the $800 to $1000 range. 

    Accessories for the barrel:

    There are two vital accessories that go with any 55 gallon drum: a bung wrench (see pic above) to open and close the drum’s bung holes easily (it apparently can also be used as a gas shut-off wrench) and a siphon pump to get the water out of the drum. There are nice, solid pumps sold for frequent use, but we got a cheap one ($20) and hope it will hold up in our hour of need.  All our equipment came from a surplus store, but many retailers can be found with a little simple googling.

    Alternatives:

    You might find sturdy 5 gallon water containers more versatile, both for handling and storage. And choosing them instead of a drum will preserve you from ever having to say “bung hole” out loud. Just make sure they are strong, BPA free, and suited both for stacking and long term storage. The less expensive ones may leak, and can’t be stacked. Find them at outdoor and surplus stores, and online.

    If you want to recycle, you can store water in plastic 2 liter soda bottles. Don’t use the white milk jug-type containers (whether they held milk or juice) because they don’t age well and don’t seal well. Glass jars are nice because they’re not plastic, but they are heavy and must be carefully stored.

    You can just store commercially bottled water. If you do this, change it out according to the expiry date.

    Cleaning the container:

    Whatever container you use, clean it first by washing with soap and water if necessary, then rinsing it out with a mild bleach solution (1 tsp in a quart of water). Bleach is what The Authorities always recommend. I’m no fan of bleach, but in this case have decided to toe the line instead of trying vinegar instead, because I just don’t want to take any risks in this case.

    Filling the container:

    City water is already treated with chlorine or chlorine variants, so if your house water comes from a municipal supply line you don’t have to treat it by adding extra chlorine or iodine prior to storage. You can store untreated city water for 6 months.

    If your water comes from a well or other untreated source, then you should treat it prior to storage by adding 1/8 teaspoon of regular, unscented chlorine bleach to each gallon of water.  

    Treating dodgy water:

    If you suspect that your water is contaminated–for instance, if after an emergency you doubt the cleanliness of the water from the tap, you should take steps to purify it before drinking. These are things to commit to memory, or maybe pin on the fridge, because in an emergency, you probably will not be able to check the internet.

    Boil it:  If you have the fuel, you can purify water by bringing it to a rolling boil for 1 to 3 minutes. 

    Bleach it: Even if you’re a bleach hater, like me, you should keep a small bottle of unscented, regular (not color safe, thickened, etc.) chlorine bleach on hand for emergencies.

    Add 16 drops (1/4 teaspoon) of bleach to each gallon of water. Shake, and let sit for 30 minutes before drinking.

    Iodine: If you have liquid 2% tincture of iodine, add 5 drops per quart. If you have tablets, follow the manufacturer’s instructions. Apparently adding a pinch of powdered vitamin C or orange drink hides the iodine flavor. And prevents scurvy!

    The preceding directions are for clean-looking water. If your water is cloudy, you will want to try to filter it as best you can to remove sediment (filter it though a coffee filter or t-shirt or somesuch), and then be extra rigorous in the purification. Boil longer. If you’re using bleach, you should be able (unfortunately) to detect a faint odor of bleach in your water after treatment. If you don’t, it’s not clean. Repeat the process. If you’re using iodine, use 10 drops per quart instead of 5.

    ETA: Forgot! Another way to disinfect water in an emergency situation is through solar water disinfection, or SODIS. Basically you fill up a clear plastic (PET) liter bottle–it has to be clear, and it can’t be bigger than a liter–and put it in intense sun for 6 hours. Filter the water first if it’s dirty. See AfriGadget for details.

    Storage length:

    Stored water should be swapped out for fresh every six months (except for commercially bottled water–again, check the expiry date on that). Use the old water for your garden, sanitize the containers and refill. We’ve got the swap date marked on our calendar so we don’t forget.

    Where to store the water:

    Somewhere dark and relatively temperature stable. Also, no matter how sturdy the container, there is always a chance for water leaks, so you should keep that in mind, too. We live in a very mild climate, so we’re keeping our barrel in constantly shady, protected corner of our back yard.

    Some resources:

    How to Store Water for Drinking and Cooking (PDF from Penn State)

    Backpackers Guide to Water Purification

    FEMA Preparedness PDF

    Dry Farming

    Jethro Tull–the agriculturalist not the rock flutist

    According to a 2010 report by Ceres “Water Risk in the Municipal Bond Market,” Los Angeles ranks number one in water supply risk. But we’re not alone. Many other US cities including Atlanta, Phoenix and Dallas also face a future of water insecurity.

    Due to these water risks we’d all do well to consider ways to grow edibles without supplemental irrigation. This may sound absurd at first, but I’ll note that in our garden we’ve discovered, quite by accident, that many plants such as prickly pear cactus, cherry tomatoes, cardoon and pomegranates will do just fine in a climate where it doesn’t rain for six months out of the year.  Scott Kleinrock at the Huntington Ranch proved that you can grow chard in Southern California with almost no irrigation through a hot summer (the chard thrived in the Ranch’s food forest under almost complete shade).

    As an avid gardener in a dry climate I certainly use a lot of water for my vegetables. Most modern vegetables are adapted to copious watering. But this was not always the case. A classic book Dry Farming by John Andreas Widtsoe, first published in 1911 and available as a free download in Google Books, describes how many farmers got along without the modern conveniences of supplemental irrigation.

    A dry farmed wheat and alfalfa field in Wyoming from Dry Farming

    Other than the advice to till frequently (tilling, among other things, destroys beneficial fungal networks), Dry Farming has some good tips:

    • Maintain soil fertility 
    • Plant deeply
    • Plant varieties adapted to dry farming
    • Know when to plant
    • Pay attention to soil structure

    The main takeaway for us home gardeners will be the development of drought tolerant veggies. Native Seed Search is a good start, but seed saving will be the ultimate solution. We’re simply going to have to breed drought tolerance back into our water hungry vegetables. Combined with passive water collection techniques such as sunken rather than raised beds, those of us in arid climates can grow a surprising amount of food with a lot less water.

    Clarification: dry farming is not growing during the rainy season (which is called “rainfed agriculture”). Dry farming uses strategies to store water in the soil during the rainy season and then grow during the dry part of the year. Though controversial, dry farming traditionally involves tilling.  It also requires much greater spacing of plants. For more information see the website of the California Agricultural Water Stewardship Initiative.