Solar Cooking

What encourages me on seeing this type of report and a similar one earlier which may be the same is that we are trying to produce new tools to do old tasks in better ways. This is not a minor consideration. It means that real awareness is been woken and people are open to new ways.

It is never easy. In this case the new device needs high sunlight. It may end up been used to simply heat a lot of water and to make the daily stew. That is good enough since the biggest energy user is just that.

Charcoal and wood are costing the users in the tropics and diverting a big chunk of the need with a cheap capital good such as this is important to people there.

One think little understood is that the world of the traditional subsistence farmer or peasant is presently passing through a fiscal and material revolution everywhere in the world. This is very easy to discount, but simple devices such as this and the advent of microfinance is reaching these people everywhere. The results are hardly instant but they are nonetheless tangible and cumulative.

If one takes a generational viewpoint, then the change is immense everywhere.

Solar-Powered Cooking

Plexiglass helps trap the suns rays and provides a means to cook without fossil fuels or wood
By Katherine Harmon

http://www.scientificamerican.com/article.cfm?id=solar-powered-cooking&sc=CAT_INNO_20090717

One little solar cooker aims to take a big bite out of climate change. The Kyoto Box, designed by Norwegian entrepreneur Jon Bøhmer, is intended as an alternative for millions of people who burn wood to cook food and boil water. Using energy from the sun can reduce carbon emissions as well as deforestation in countries such as Kenya, where Bøhmer lives and runs his company, Kyoto Energy.

Bøhmer experimented with the concept for a decade, inspired by the simplicity of a solar device invented in 1767 by Swiss physicist Horace-Bénédict de Saussure. The cooker, which consists of two boxes nestled inside each other and topped with Plexiglas to trap the sun’s rays, has evolved from a homemade cardboard contraption to a $6 plastic version that went into mass production this spring.

Environmental benefits aside, the Kyoto Box holds promise for human health, too, by allowing people to effectively boil unsafe drinking water and to avoid harmful smoke inhalation from toiling over sooty wood stoves. Bøhmer is also investigating whether the cookers could eventually pay for themselves or even become a source of income for families, if Kyoto Energy can qualify their use as a source of carbon-offset credits. “As the world gets more and more technically complex,” Bøhmer says, “there is a certain relief about something so basic and direct.”

Mel Landers and Jackie Foo on Field testing Corn Stover Stacks

The following posts from the Black Earth Soils newsgroup (Bionet) are well worth reading since we are addressing the possibility of restarting hand production were it is the only option.

Mel Landers:

arclein wrote: Their principle option was to use corn stover and I show how.

Thank you for sharing this idea. This is very helpful. Having grown Maize for a number of decades now, I can attest to what you have stated about its stacking capacity.

I also know the difficulty in utilizing Maize stumps if you don't burn them. (not that I ever thought to do so) The Amazon Basin can grow an amazing amount of biomass in a short period of time. (I have attached a photo I took four decades ago, when I introduced slash and mulch methods to the Urarina of Peru. It shows the abundance of biomass left on the soil after cutting tropical kudzu.) But, maize is a challenge to grow in that environment. The fact that maize pollen is so common attests value of dark earth soils and their ability to retain nutrients.

It makes sense that, women would long ago have turned to firing their pots in order to increase their strength and longevity. The clays in the upper Amazon Basin are high in sand. The area is one big flood plain with continual deposition of sand. If the same is true in the lower Amazon, their pots likely needed firing. I have also attached a photo of an Urarina woman making a pot. Notice the grey color of the clay. The pot I brought back with me had a very rough texture, due to the sand.

Why not turn to maize stumps to produce a high temperature fire. Place that fire under the soil, in an impromptu dirt oven, and you have maize charcoal. It would be easily powdered and once your soils started improving, it would have been plentiful as well. It is a short step ahead to do the process specifically for soil improvement. If anyone doubts that they might do this, they need to read the information written up by Suzanna Hecht on the practices of the Kayapo.

Here is a type of biomass that is even plentiful in the temperate zone. O.K.....I can hear Bob thinking....But, how can I stack the Maize stumps from a whole section of land. That is where a large scale pyrolysis retort comes in. But, here in Nicaragua and in many other maize growing regions of the world. Stacking by hand makes good sense.

Nicaraguan producers already think I'm crazy for wanting the grass they cut off the fields in preparation for plowing. Now they will think I am totally insane for requesting their maize stumps as well. This should be interesting! Thanks again!

mel

This is an excellent validation of the proposed mechanism

arclein wrote:

Hi I did a post describing a method of producing terra preta soils using only primative stick agriculture. Their principle option was to use corn stover and I show how.

I am hesitant about other feed stocks in general been as forgiving as corn stover, but that has to be shaken out through practice.

I also describe a modified incinerator design to utilize a full range of biomass in later posts.

The astounding revelation is that the Indians sustained continuous agriculture in the Amazon for centuries.

See my post at:

http://globalwarming-arclein.blogspot.com/2007/07/ carbonizing-corn-in-field.html

This has turned out to be my most popular post to date. Enjoy the site.

From Jacky Foo

Hi arclein

I checked your profile at www.blogger.com/profile but found no "real name" and therefore I address you as "arclein".

I have not made charcoal nor charred materials before and therefore I ask you.

Q: have you tested your idea of "carbonizing corn in the field" as described (Wednesday, July 4, 2007) in the link provided above ? or is there a drawing of what you described anywhere ?
>...the Indians in the Amazon likely created windrows that they
>then lightly buried and set afire. Your idea sounds very logical if the Amazonians were making charred materials (from corn stalks with their roots intact). But did they make charred materials to fertilise their soils or was charred materials simply a by-product of their burning away of agricultural wastes (corn stalk and tapioca stems) ? . (your message of Friday, July 6, 2007 "Those amazonian soils" in:

http://globalwarming-arclein.blogspot.com/2007_07_01_archive.html .

Given that we now want to make charred materials and we have corn stalks with their roots intact, the idea of stacking a windrow of two rows of corn stalks with their roots to form the outside walls is a good one.

So let's say I have 5 acres of corn where I could get 50 tons of stover. I have no machinery (nor container to make a kiln), just bare hands of the workers e.g. in Kenya.

How big (length and height) would this single windrow be ? What materials can I use to make the outer wall ? ...etc

regards jacky foo

arclein wrote:

However they began doing this, the rewards were immediate inasmuch as the soil retained fertility that would have completely disappeared in perhaps three years.

The volume of corn stover made this possible over the whole growing area so that there was no lack of biochar even at the very beginning. Most other likely sources would restrict you to treating a fraction of the original cropped area and likely not be very sustainable.

Right now, we are speculating. I would actually try to build a circle with the roots on the outside and see if it is possible to build a beehive shape as an experiment. I would leave a central chimney, probably because I had to, and fill the bottom of it with a well stamped mass of biowaste.

Once the beehive had reached the point of almost been closed off, I would throw a large mass of glowing coals into the chimney and then fill the chimney with corn stover with a dirt capping. Then I would stand by and shovel dirt on any breakthrough for the next few hours.

We can try other methods of stacking once we have a little experience. And no, no one has done this yet and I am keen to see how it goes.

regards

arclein