Adventures in Solar Cookery

This summer with Peris and Mary we explored a subject that has great potential in Kenya, as it does here: solar cooking. In Kenya a significant amount of time and/or money goes into fuel for cooking. Either you pay for coal, gas, or wood, or you wander far and wide (and risk assault) looking for a source of wood, which is scarce in the largely deforested country. The capacity of sunlight to heat a surface offers an endless supply of energy which, when used passively, doesn't even require much in the way of raw materials to harness it.

Much credit for spreading the word about solar cooking must go to the organization aptly named Solar Cookers International. Former Ecology Action Garden Manager Carol Cox was fascinated by their work, and taught many years' worth of EA interns how to make simple and cheap cardboard box cookers. Which is how we, in turn, learned how to share the low-tech, high efficiency tool with others.
Our first foray into the world of solar cooking actually came in the form of a wedding present from our friends Sarah and Jim. This Sun Oven is a portable, high-powered solar cooker that involves a collapsible reflector, adjustable prop, and and a few other features that even make it possible to bake bread (at left) on a clear day.
The one Carol taught us to make, while not as powerful, is still capable of cooking grains, potatoes, meat, etc., pasteurizing water, and canning fruit and tomatoes. It involves two cardboard boxes, some glue, aluminum foil, silicon caulk, and a piece of glass. Plans can be found on the SCI website in book form for a mere $7. The book includes recipes and principles of using the box cooker.
Last but not least, the product of another gift... The Jeavons' gave me a book called The Solar Food Dryer which, among other things, gives plans for building an entirely passive-solar food dehydrator (no electricity involved). Aficionados of the Golden Rule Garden blog will undoubtedly have read my post on constructing it back in 2009, but for a much clearer explanation of the process check out the Gardenerd blog post on the topic. After building a third iteration, pictured at right, I only have a couple points of advice to add to the dialogue. First, the book recommends using stove paint on the metal heat collector. While this paint is good to 1,200°F, it is faaar from environmentally friendly. Plus it's $13 a can. This time I used a few coats of black tempura paint, which is not as durable, but is much cheaper and much less toxic. Second, this time I had to actually go out and buy a piece of metal for the heat collector, and found sheets of galvanized steel for something around $22. But galvanized ductwork was more like $13 for the same area, so I got that and banged it flat. And finally, the screen that the food sits on to dry: I like cheap, but this time I bought the stuff that the book recommends instead of using free (but icky) aluminum or fiberglass screen. And you know what? The dried food comes off like a dream! Well worth the $18-$20.
Without going into great depth on cooking pointers, the basics to solar cooking are as follows: It generally takes more time to cook with the sun, and this is the only downside. The upsides are many. Since there is no danger of your food (or your house) burning if you leave solar cooking food unattended, you can put out a dish in the morning and leave it till lunch or supper. Because of the nature of solar cooking your food will not dry out, and will often be much more moist and flavorful than food cooked on a stove or in a standard oven. And the cardboard box cookers (at left) are very inexpensive to build, so by making a few of them you'd have the capacity to cook for a great many people at once, with no fuel, while you are yourself working somewhere else the whole day long! Even in our climate, with the presence of cloudy days, solar cooking is tremendously practical. It merely takes an understanding of the principles and a willingness to work with the weather.
The solar food dryer, too, is dreamy. In its very first batch, our new one simultaneously dried tomatoes, basil, and bananas (see the close-up at top). The tomatoes and basil have been gracing our sourdough bread for the past couple of months, but I must confess that the bananas didn't last a day before being consumed. I don't have as much experience as others in its use yet, but the aforementioned Gardenerd blog has advice on making Flax Chips and Kale Chips, and drying mint and leeks with the solar dryer. I can tell you, though, that even in this humid climate this simple dryer works well.
I'd encourage anyone interested to give it a shot. In the worst case you'll come out with a conversation piece. In the best case you will change your diet, cut your fuel costs drastically, and become a calmer, happier, and more charmingly eccentric person!

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Everything Old is New Again

I'm a big fan of taking that which has been used and making it useful once more. Especially when it can be turned into something I reeeeeally want. Pallets have done a lot for us in the past year but, though they are versatile, they couldn't help me on this project.

What was on the docket in this instance?

We were spoiled in many ways being on established farms, and one of the greatest elements they each offered was season extension. Particularly in the area of seed-starting. We'd been wishing all last year for somewhere to put our starts that would be out of the excessive cold, heat, rain, snow, and such, but didn't have enough acceptable indoor window space.While I would like to have a greenhouse (ideally one big enough to house a full-grown avocado tree) we didn't have the supplies on hand for that. In fact, at the onset of winter, which is project time, all we had was the hoard of windows that were removed from Mom's house when she put in energy-star windows. And the old ones were the original single-pane variety, most with original glass, I imagine. And, greedy me, I wanted something that wouldn't let all the hard-earned warmth seep out.

This is where our contractor friends came in. They build, they renovate, they remodel, and they replace old windows with new ones. A lot of times, they told me, the old windows aren't all that bad. Over the course of a month, then, I got: one 6'-wide sliding glass door, very nice; a 6'-wide hinged glass door, somewhat nice; four double-glazed windows, two without their frames; and a transom window, which I didn't use. Margo's dad has done the same project at their house, so I got four more windows from him. All free, and diverted from a landfill. Margo's dad would probably have found a good use for them, but our other two friends assure us that that's where most casualties of remodeling go.

For a greenhouse I would need three or for times as much glazed surface as this, plus the thought put into corners, a roof, and an independent structure to support the whole thing safely. In the meantime, though, I had already found what I thought would be the ideal temporary situation: Mom has a shed at the end of the drive, and that shed has a south-facing garage door. I figured I could just frame the opening of that and put the doors and windows in, which I proceeded to do.

Other, more experienced individuals might have jumped right in and gotten the whole thing done in a day or two. I, however, have no particular experience with this kind of thing, and took it slow. I also have an 8-month-old, so that made things a little slower yet. But with advice from Margo's dad, and a little physical help from my friends, I got the whole thing assembled. The results are very pleasing: on average the temperature inside the shed is 12°F warmer than outside, with the added benefit of sunlight and shelter from the wind, rain, snow and ice that have since bombarded it. The kale, cabbage, alfalfa and clover are up, and the leeks and onions are starting to pop out. Hurrah!

There were a number of steps after the windows and doors were procured. After measuring the size of the opening and the dimensions of the windows I made little paper cutouts of them all, then played Tetris with them. This part would have been extra work, except that a few of the pieces weighed 100 lb or more in real life. Easier to move around paper cutouts. Once I found a setup that worked, I marked the area out on the shed floor, put the windows and doors down, and measured to see if it really worked out. It did, mostly.

What I didn't have yet was the lumber to frame it, but I had a contact for that, too. Our family doctor, who lives a few minutes down the road, had a new office built a while ago. She said the construction crew had this big dumpster, and she was amazed at the things they threw in there. So she would often check it and take out any wood she thought might be useful. She invited us to take anything we might need. Between that and some scrap barn wood, I had all the 2x4's I could use. So I measured once, twice, sometimes thrice, and cut. Again, it worked out mostly, and any mistakes were readily corrected with a chisel.

It was 9' high, 16' wide (but not soft as a downy chick) and just a little too unwieldy for me to manage alone, so I called up a couple of friends to help me move it into place. Zach, Seth, Mom and I got it moved where it should be, "finessed" it into place with a mallet, and finally screwed it to the opening.

Over the course of the next week or two I seated each of the windows and fixed them with beveled trim (thank you, table saw) to hold them in place. I have some silicon to seal the cracks, but I'm not sure if that will really make a difference.

As I said, the whole process has had a good result. Better would be if the shed were insulated - it has plywood exterior with vinyl siding, no ceiling, and vents in the "attic" space. But it works good enough for starting plants, has opening windows on all sides to keep moisture from rotting things, and is sturdy. So I'm not complaining.

This project, from supplies to advice to labor, could not have been done without the community of friends and family that I can claim. Or, rather, it could have been done for a moderate expense. But all I bought were screws and nails, and that was it. And, while Zach and Seth were over helping, their families, plus Margo and Alten, were in the warmth of the house enjoying cheese, crackers, and play-doh. It was like a very small barn-raising :)

For anyone else out there interested in building with windows and doors, my main advice is to find a company or individual who does renovations. I understand they are happy to have a positive use for the windows they remove; they feel good about not throwing away perfectly good windows, but are also saved the expense of hauling and depositing them at the dump.

As a side note to any of you serious writers and editors out there, you may have detected my relatively frequent use of the consummate (though nebulous) semicolon in this post. In the same way that I hope to have built a pseudo-greenhouse that won't fall apart, I hope I applied the semicolon appropriately. But then, if you don't try, you'll never learn!

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Cleansing Our Pallets, Part II

The internet will back me up on this: there are endless uses for the ubiquitous pallet. And, in this case, necessity is the mother of invention. My necessity was to get rid of extra pieces of pallets that wouldn't work for building flats. Believe it or not, all those "waste" stringers I mentioned in Part I were the perfect material for something else I didn't even think about needing: tables to put the flats on! Construction was very simple. Each table requires 11 stringers, which you can get from three or four pallets (depending on their design). I started by removing the extra wood and nails from them. This step isn't absolutely necessary for the legs and top surface, but it looks much nicer and you won't have nails grabbing you as you walk by.

I had removed the boards for flat material by cutting right along each stringer with a circular saw. That left the stringers you see in the photo here, complete with pieces of board still nailed in. I found I could break these off of the nails easily with sideways hammer blows. I was left with nails that could not be pulled out. Most would allow themselves to be hammered in, some were bent and hammered flat.

All of the stringers were 48" long, so I let that dictate the length and width of the table. Two stringers would form the crosspieces, making the table 48" long, and five stringers would be cut in half to make ten surface pieces for a 24" wide table. The legs were cut to 37" to create a reasonable height. I chose the six straightest, flattest, and strongest stringers for the legs and cross-pieces.

I assembled the surface first, laying the 24" surface pieces flat on the cross pieces and nailing them. The gap between each was something like 1½". Then I upended the surface and attached the legs with screws. I spent some time making sure they were square before affixing them, but it turned out not to make a clear difference. They were a little wonky anyway.

When I righted the whole thing it was obvious that it was not so stable, so I added the diagonals you see in the photos. They were scrap flat material.

I needn't state that beauty is in the eye of the beholder, and that function often comes before aesthetics for me. If I find that Warren Buffet writes me into his will I may commission an Amish cabinet maker to fashion me some nice mahogany flat tables. Until that point, though, I will be very pleased with these. They are sturdy enough to jump up and down on (our seedlings do a lot of that), durable enough to last at least a few seasons, and were free wood.

Cleansing Our Pallets, Part I

As indicated in the previous post, we have a long list of things to accomplish to get our garden off the ground. Some of these are common springtime needs even in established gardens, but many fit under the category of infrastructure. Like flats. And this is the story of our (currently) fourteen flats.

Back in northern California we used redwood for our flat materials, both because it has great anti-rot qualities and was local. Here cedar is the equivalent, but both woods are a little too pricey for us. Not just because they are expensive, but because they cost money. You'll hear it from me often that time is a resource we have in abundance while money is much less so. Anything we can save money on by creating through time and/or expertise is a great opportunity.

Here's where a local business that we frequent comes in: at our inquiry they said they had broken pallets they didn't want, and that we would be welcome to take them away. (When we arrived it turned out they were happy to give us some unbroken ones as well!)

So with seven pallets, a circular saw, table saw, hammer, one pound box of nails, and some time we got fourteen flats, a bunch of broken pieces of wood, and the stringers with nails and things still in them. I went with half-flat sizes, as defined in How to Grow More Vegetables, with interior dimensions of 3 x 11½ x 14", since they are easier to carry and more versatile for us.

Initially I thought I wasn't going to have to buy nails, since those pallets have so many in them already, right? I'll just pull them out, straighten them, and reuse them, just like grandpa would have. This turned out to be much more work than it was worth. These nails are shot in with nail guns, are extremely hard to get out without breaking off their heads, and can't be nailed back in because they don't have sharpened tips. In the process I broke a number of good boards, which would have brought my flat total up to fifteen or sixteen, and got frustrated. I ended up writing off the nails and cutting right beside them with the circular saw.

The boards, of varying sizes and widths, were then all cut to 14" on the table saw (to make things easier). Most were about 3½" wide, so I ripped them all to that width. Then I went through to determine which boards would be best on the long sides of the flats (I used the thicker ones, since they would get all the nails pounded into them). The long side boards remained at 14" and the rest were cut to about 12¾" for the ends and bottoms of each flat. Then I stuck them all together and reveled in flats.

I was sitting there looking at all those stringers, thinking there had to be something useful to do with them. Then I realized that flatting tables would also be really handy, so flats could drain and be above chicken-head level. So after a little more experimentation I built some of those. Pictures to follow.

In the process I learned a few things. First, although I thought pallets were always made of cheap softwood, I found out that sometimes hardwood is cheap, too. It's hard to cut, and even harder to pound nails into when you aren't expecting it. But it looks respectable! Second, drilling pilot holes for nails takes some time, but is worth it when all of a sudden you aren't spending half your time pulling out bent nails. Finally, and perhaps most importantly, I found out a bit of information on Wikipedia while trying to figure out what "stringers" were called. That is that sometimes pallets are fumigated with nasty things to keep them weather resistant. Honestly! Can't we have anything fun in life without threat of carcinogens? So my second set of pallet flats will probably be the last, at least until I know exactly where these pallets come from.