My work and other projects around here

I don’t want bore anyone with minutia and technicalities regarding my work, but I should at least give an overview of what I’m doing as well as of the variety of projects that are being undertaken in Sabana Grande. 

For me, the first week was taken up attending the solar course, which included tours of the facilities and installations in the area as well as more traditional course-type work on solar thermal and solar photovoltaic systems.  The solar thermal material was old hat, but the photovoltaic material was more novel.  There was also an afternoon session with a summary of Nicaraguan history, culture and politics.  We had the opportunity to repair existing solar cookers for most of 2 days and spent about a day debugging electrical problems with the main panels at the Centro Solar.  We also made solar battery chargers more or less from scratch.  The silicon cells, of course, were purchased, but we soldered, laminated, mounted and wired them.  An interesting (hopefully!) side-note is that the cells here at the center are typically rejects from cell manufacturers, which are cut and salvaged locally.  Up until now, the emphasis has been on local fabrication of the panels from these cells, thus saving some money and giving employment locally.  About a year ago, it became cheaper to import completed panels from China than to purchase rejected cells and fabricate here.  Seems to be a familiar refrain these days...

Solar panel array at the Centro Solar.  Debugging some electrical problems during the course.  The wooden ladder is home-made and the aluminum ladder is not quite tall enough, but then there's no OSHA in Nicaragua.  (This fact is evident over and over wherever one looks.)

One session of the course has morphed into my initial project.  I say initial because things are very fluid here and if the need (or interest) is greater elsewhere, I could switch to something else.  The primary course instructor, Dr. Richard Komp, brought a concept for a collapsible, portable solar cooker that could be easily transported by burro (or llama or camel or even taxi) in remote locations.  We hope to turn this concept into a prototype to test the ideas before I leave.  I’m doing this in conjunction with the solar cooker construction team (a group of 6 women who concentrate on cooker construction and repair).  In the states, with a reasonable budget and access to hardware and material, this would be perhaps a 2-week project.  Here, to find a simple hook and eye like you find on screen doors took a trip to Ocotal and three different hardware stores;  I never did find a buffing wheel and compound.  (Hardware stores here are an eclectic mix of high tech, really nice power tools and accessories with almost no selection of items such as nuts, bolts, screws and nails.)  Susan may be serving as a courier when she comes down in March as there will no doubt be some things we want to try that are not readily available locally.  I’ve met with the team leader and we’ve already identified a couple of problematic areas with the concept, but are still working on a viable alternate.  Since the project is just beginning and in the concept phase, there are no pictures yet.

Other Grupo Fenix projects

Other than my work, there are many other projects that have been done, are in progress or are in the planning stage.  First, there are three different entities here under the Grupo Fenix umbrella, but with considerable overlapping.  The Centro Solar is the oldest of the three and is the place where the technical work on cookers and photovoltaic panels is done.  The Casita Solar is a restaurant next to the Centro Solar that only opened a few months ago and as of now is only serving volunteers, course participants and an occasional pre-scheduled meeting for outside organizations.  Eventually it is hoped to become a more traditional restaurant open for traveler on the Pan-Am Highway.  (An official grand opening will occur this week, complete with TV coverage.)  Finally, the Montaña Solar is a property that is being used for projects/experiments in reforestation, perma-culture, sustainable/organic farming, drip irrigation and natural building.

 For Centro Solar projects, pictures are the easiest way to give a quick overview.  The pictures follow and captions give a bit of information about each.  Pics of the solar panels were shown above.

The Centro Solar seen from the gate with my back to the Pan American Highway.  The solar panel arrays are on the right and the Casita Solar is about 100 m directly to the left.

A solar distiller.  It is designed to be fed automatically from the large black plastic bottle (currently on the ground) and feed the distilled water into the plastic jug.  The water is for the batteries at the center and also for sale as a cash-flow source.

A parabolic concentrating collector with the pot placed at the focus.  This one is capable of burning or igniting things if left unattended.

A trough-type parabolic concentrating collector on a cooker.  This is a donated commercial product and uses vegetable oil as the heat transfer medium.

A prototype solar autoclave.  It is mounted like a wheelbarrow with individual mirrors focusing on a plain old Presta pressure cooker embedded in the plastic bucket with foam insulation.  The mirror arrays should fold up along the acis of the cart allowing it to fit through doors, however, the wood frame is not rigid enough the focus is lost.  And if in losing losing the focus on the pressure cooker, you gain a focus point on the plastic bucket, that's bad news!

Another project of the Centro Solar occurs off-site and is the making of charcoal from agricultural waste, primarily corn stalks, which would otherwise just be burned in the field.  I participated in the production of one batch of briquettes.  It’s really a rather simple process, but a bit time consuming and very messy!  Any kid who like finger painting would love making charcoa!  I'll post a few pictures showing the main steps in the process.

The beginning of the charcoal process.  The corn stalks on the right are broken up and stuffed into the barrel (with holes in the bottom).  A fine is started and after some time, flames start to appear (as shown).  The flames are allowed to burn for about 10 minutes, then the barrel is covered and sealed both on top and at the bottom with dirt/sand.  It is then left to smolder and cool by the next day.

The burnt cornstalks are crushed by dancing on a grain bag full of stalks.  The cauldron has a mixture of water and grated yuca (cassava or manioc my dictionary says) to form a starch paste.  This is then poured into the other basin and mixed with the corn-stalk powder until it clumps in the hand.  (William should recognize the woman in the cap:  he stayed with her family when he was here 3 years ago.)

The starch-carbon mixture is then stuffed into steel molds and hammered until well compacted.

yuca (cassava, manioc)

The formed briquettes are then ejected from the molds and spread out to dry.  The briquettes in the foreground are drying while a second batch is prepared to mold.  A barrel-full of corn stalks yields about 80-90 briquettes.

The Casita Solar includes many sustainable features often in conjunction with projects at the Centro Solar.  Among these are several alternative cooking methods:  solar cookers, bio-gas produced from the latrines, high-efficiency wood and charcoal using locally produced charcoal.  There are also solar panels/batteries sufficient to run a high-efficiency deep freeze as well as lighting.  They also have a bicycle-powered blender and are looking at other pedal-powered appliances.

The Casita Solar restaurant with the open-air dining room in the front and the kitchen in the back.  The biogas toilets to the right are the only flush toilets in Sabana Grande.  You can't see in the picture, but there are high voltage lines directly overhead, but the restaurant and Centro Solar are both off-grid.

Baking a cake and roasting coffee beans in one of the solar cookers at the restaurant.

A higer-efficiency wood stove and a couple of charcoal burners in the restaurant kitchen.

A second high-efficiency wood stove in the restaurant.

The gas stove that uses biogas produces by the toilets.  The manometer gives the pressure in the digester and they can cook about 5-6 hours at the maximum pressure.

The Montaña Solar is currently a beehive of activity.  Many of last year’s tree plantings (reforestation project) are now watered (by bucket) 3 times per week, but the established trees are able to survive the dry season.  An MIT student is working with a group on a gravity-fed drip irrigation system for the garden and potentially some of the trees as well.  Water will come from a solar-powered pump pumping water to a water tower.  A small warehouse/shed is being constructed (corrugated metal) to hold tools and other materials.  A kitchen is also being built of brick and plastered adobe.  This kitchen will be used to prepare sale items using fruits/vegetables from the trees and gardens, such as jams, jellies, cookies, etc.  A new, elevated, composting latrine is also being built which is the Taj Mahal of latrines.  (It will most certainly be featured in the 5-star category in my forthcoming special latrine post!)  Finally, there is a natural building class with around 15 participants who are putting up a natural building to be used as a classroom/office space.  They hope to have the building 99% finished within 2 weeks.  I got to help a little on pre-course preparations, including going on a bamboo-harvesting expedition.  It’s a much different kind of construction than "standard" in North America, but very interesting to watch the progress.

A group of recently planted trees in the reforestation project.  They plant a variety of trees to maintain more diversity and prevent disease.  The inverted bottles are the way that roots are watered without losing a lot to evaporation.

Another section where banana and castor are planted.  Caster is also planted with the coffee trees to provide shade.

 

New natural building showing the foundation and framework.  The foundation is bags of rock/sand that will be completely covered both inside and out.  You can see the stone facade started on part of the foundation.  All the materials are local.

Starting to add a mud-straw mixture to the walls.  The walls demonstrate various techniques, hence the wire mesh on one wall the woven bamboo on another.  The bamboo was harvested about a kilometer or so from the site.