A women’s agave syrup cooperative in the state of Hidalgo, Mexico, has just completed the construction of a commercial, solar powered kitchen built by Gregor Schapers, a German national who lives in Mexico.  Gregor has been designing, building and selling solar hot water heaters and parabolic Scheffler reflectors in the state of Hidalgo for the past five years.

 

The women of this cooperative have since 1989 been harvesting the sweet sap of the agave plant and boiling it down (an 8 hour process) to make agave syrup, a thick dark liquid that resembles molasses.  Fifty liters of the sap are needed to produce five liters of syrup.  A 250 ml. bottle is sold locally for about $3.00.    Agave syrup is considered to be a healthy sugar substitute (see article in next message).  It has a growing market in the U.S. health food industry.  

The women of this cooperative had been using bottled gas, which was rapidly becoming too expensive given skyrocketing prices and the amount of time needed to render the sap into syrup.

 

The coop received a $15,000 loan from Swiss NGO Globosol to hire Gregor to construct a long kitchen extension for their cooking pots and to build the six parabolic Scheffler reflectors, which will generate the heat for boiling the agave sap.  Timers (small photovoltaic cells) set each morning, move the reflectors automatically to track the sun all day long, keeping an intense beam of sunlight focused on an opening into each kitchen bay where a pot of agave sap is boiling.  I will be editing a video, which shows the process in detail. 

  

The payback rates on the $15,000 loan will be based on the amount of cooking gas saved every month by using the parabolic reflectors instead of bottled gas to boil the sap.   Gas burners have been installed in each cooking bay so that cooking can continue uninterrupted on the rare cloudy day. 

 

The women of the cooperative have been trained to carry out the minimal maintenance required for the parabolic reflectors, which are made of welded steel tubing and hundreds of small ordinary mirrors.  This maintenance includes:  monthly oiling of the moving gears that track the arc of the sun; daily hosing of the mirrors; a weekly adjustment of the tracking mechanism to account for the seasonal changes in the tilt of the earth; and repainting the welded steel frame once every two years.

 

The purpose of this Rotary International-sponsored workshop was to introduce the people of the Tepeji del Rio region to integrated solar cooking and encourage them to save money and preserve their environment by using sunlight and other supplemental methods to dramatically reduce the amount of fuel needed to cook food and heat water.  Many people told us they were no longer able to afford cooking gas and had reverted to cooking with wood and dung.

The construction and proper use of the three integrated cooking devices (solar cookers, retained heat cookers and rocket stoves) were demonstrated by our team at the Santiago Tlautla School during a one-week workshop, which coincided with an annual Rotary-sponsored medical clinic that drew hundreds of families to the school.

My primary purpose in attending the workshop was to learn how to construct rocket stoves using found material.

Men and women attending the workshop were taught to make three types of rocket stoves by their original designer, Larry Winiarski.    I am editing videos, which will be posted on YouTube showing the construction of each of these devices.

1. A sixteen-adobe brick rocket stove:  click here to see YouTube video

All three stoves were constructed using locally available materials.  All three produce an intense smoke-free flame using small amounts of wood.

Two types of solar cookers were demonstrated at the workshop:  the Cookit and the Hot Pot.  One hundred Cookits and more than fifty black cooking pots were sold during the workshop.  Local foods were cooked and sampled each day on the school patio.  During the final two days of the workshop, after all the Cookits had been sold, women were taught how to make their own Cookits using cardboard, glue and found bits of reflective material (cigarette wrappers, gum wrappers, juice boxes, mylar).  A number of women also expressed interest in purchasing the more expensive and more durable Hot Pot, which is manufactured in Mexico. 

 

Women at the workshop were also taught how to cut up old sheets and sew them in to large pillows, which they could stuff with crumpled newspapers, magazines or bits of Styrofoam to make retained heat cookers.  The two pillows, which when placed in a cardboard box on top of and underneath a cooking pot filled with hot food, can extend the cooking process for another hour and will keep food piping hot for an additional three hours.  By using a retained heat cooker, women can solar cook a pot of food in the afternoon and serve a hot meal in the evening using no fuel at all.  A retained heat cooker also allows them to begin cooking over a fire and complete the cooking process in the insulated container, thus dramatically reducing the amount of fuel needed.