Reporte de la estufa investigación

Just like real scientific research, my analysis and report on the experiments I did for the rocket stove took several weeks to finish after performing the experiments.  In addition to the soot measurements, I also measured water boiling time and the temperature distribution of the stove. 

Como todas investigaciónes de ciencia, mi anailis y reporte de los experimentos de las estufas terminan algunas semanas despues de terminando los experimentos.  Ademas de examiné la hollín, medí el tiempo necessario hervir agua y la distribución de la temperatura en la estufa. 

                                                                                          

The water took the longest boil when the stove was started from a cold start.  When the water boiling test was repeated when the stove was lit when it was already hot, the same amount of water too half the time to boil.  Decreasing the time to boil to half again was possible by putting the pot inside the stove (see photo).  This is why many wood-burning stoves have pot skirts.

Agua necesitó mas tiempe hervir cuando la estufa encendió de una frio tiempo.  Menos tiempo necesitó cuando la estufa encendió cuando ya estaba caliente (un medio de la otra tiempo encendió de la frio estufa).  Es posible reducir el tiempo necisario hervir a medio otra ves si pone el olla adentro la estufa (mira la foto).  Esto es la razon que muchas estufas de leñs tienen faldas de ollas.

The different temperatures of the surface of the stove were studied with an infrared temperature sensor, and also with a much more real world test of tortilla making.  When putting enough wood in the stove to get the rear burners to sufficient cooking temperature, the front burner will burn the tortillas very quickly.  But the rear burners of the stove are not hot enough for cooking tortillas when the front burner was set to the ideal heat for not burning the tortillas (by using less wood).  I did find a great way to make use of the rear burners when the front burner was at low heat; when open, the rear burners were perfect for roasting marshmallows and making s’mores.

Estudié la distribución de la temperatura en la plancha usando una herrmienta de temperatura como infraroja, y tambien hice un otra experimento mas real para hiciendo tortillas.  Cuando puse suficiente leña en la estufa para hacer la plancha altras suficiente caliente, la fronte de la plancha es demaciado caliente y las quemaré las tortillas muy rapido.  Pero cuando la fronte de la plancha puede cocinar tortillas bien como menos leña, la plancha altras falta suficiente calor y no puede cocinar.  Yo encontré una bien opción por la plancha altras cuando la fronte de la plancha puede cocinar tortillas bien; la plancha altras esta perfecto para hacer angelitos asado (o malvaviscos tostados) y u’p’mas**.

** s’mores = some more = un poco mas = u’p’mas

This stove study was on the stove designed by Alterna.  The other stoves I worked on with my Spanish school in Guatemala are discussed in their blog, including a post on our talk about soot!  

In Peru, I haven’t seen many cookstoves.  In communities near the ocean where ceviche is common, cooking isn't necessary for this dish.  Gas is also very cheap in Peru, so many families use gas stoves.  I did see some three-stone fire pits for making chicha morada in one of the electricity-free houses.  And we did build a campfire at a lagoon in the desert that would have been perfect for making s’mores and roasting fish.

Field installations

Many communities in Sechura, Peru are without electricity, at least not connected to the main grid.  We recently took a trip out there to install and maintain wind turbines for some of these communities.  Here are some short summaries, more to come later.  (Hay muchas comunidades en Sechura Peru que no tienen luz de la principal luz fuente.  Viajamos a las comunidades a instalar y arregular molinos por algunas comunidades.  Aqui yo escribo un poco sobre esta viaje, y mas a venir pronto.)

A small group of about five houses got a new wind turbine last week that we put up.  This was supposed to be the site for a pilot test of a new method to fund the wind turbines.  A meter was planned to be installed on each house that was connected to the generator, and this meter would be capable of measuring and controlling the amount of energy coming through to the house.  After a month of letting the community use the energy from the turbine for free, they would switch to having to pay a fee for the energy they use, which would eventually pay off the cost of the wind turbine, and any future excess would go back into the community for maintenance or a new turbine.  Though, based on the remote location of this community, it was not actually chosen for the pilot test of this meter technology.

Playa Blanca, a community of 49 houses near in Sechura was chosen to be the final location for the pilot test of this meter technology.  The people in this community were very excited to get a new wind turbine, and they were interested in being able to pay for the energy, therefore, this meter technology would facilitate the payment logistics.  And the meter would help ensure that families only paid for what they needed and/or could afford, and the cost could be chosen to be an improvement for the alternatives.  For examples, families who currently only needed light in the evenings could be paying less to get enough electricity to turn on an LED for several hours a night than to buy one or two candles a night (1 sole each).  Or a family who is accustomed to having electricity for a television, from a diesel generator, could be paying less for the energy from a wind turbine than to operate their generator.  Playa Blanca also has some of the best wind resources in the world, according to NASA data, so this is an excellent place to put in small scale wind turbines for the communities here.  The closest city connected to the main electricity grid is 40 kilometers away, and it is actually more cost effective to put in small scale wind turbines than to connect this community to the grid. 

We also visited a house that had already arranged to purchase a wind turbine.  His wind turbine was installed, and he was making payments of about 500 soles per month, collected in person.  This works well because the owner is very interested in making payments for his wind turbine, and WindAid is willing to come by and collect money on a regular basis.  However, this model runs into problems if either of these situations is not present, and this would be where the meter type of system would be of great help.  Many Peruvians seems to want to pay for electricity.  Before having wind turbines, many already have televisions or other electricity-powered appliances run on generators, which are expensive to operate, or batteries, which are expensive in time and money to get recharged in the nearest town.  This guy with the wind turbine loves his television and was excited to show it off to us.

We stopped by another small roadside restaurant off of the Pan American highway (forgot to take a photo).  The owner sold us some cold drinks, and mentioned how she was paying 500 soles a month to operate her diesel generator for the lights in her restaurant.  She saw our wind turbine propaganda (hats, stickers on the car, etc.) and was very interested in the product.  She could easily switch to paying 500 soles per month as a payment for a turbine and then never have to pay it again once the cost of the turbine (about 3000 soles) was paid off.

La finca de café

Here’s an overdue story about a trip to a coffee plantation led by my Spanish school in Xela.  We learned about the coffee making process, involving stuff about heat transfer.  First, we learned about differences between red and green coffee beans.  The red ones can be peeled and opened, and the green ones cannot, meaning that they have to be processed as is.  The green ones are usually the ones that get dried and made into instant coffee.

Hace algunas semanas, mi escuela de español en Xela fue a una viaje de la finca de café.  Nosotros aprendemos como preparar café y cosas en esto proceso sobre transferencia de calor.  Primera, aprendemos que es la diferencia de cafés rojos y verdes.  Podemos abrar los cafés rojos, pero no podemos abrar los cafés verdes.  Los cafés verdes necesitan preparar como fueron y a menudo estos es lo que cambiar a café instante. 

We saw three different methods of drying the coffee beans.  One is a machine from Germany (photo below left), where the coffee spins in circles while heat is allowed into the system.  Another method involves putting the coffee beans in a large pile above a grate where heat comes in through the bottom, and workers crawl through the mixture to distribute the heat and let the moisture evaporate through the top.  The last method is to let the coffee beans dry outside (photo below right), though if there is any chance of rain overnight these must be collected every night and put back out.  The machine from Germany is obviously the best method because it dried the coffee fast, within hours, and requires minimal input.  The method with the workers mixing the coffee is bad for the workers’ health, and they are always sick when working in this process.  The coffee drying outside takes days.  I asked why they don’t just build another machine like the German one.  My teacher said he wasn’t sure but it could be that the plantation owners don’t want to invest in one and take away jobs for the workers. 

Vemos tres opciónes para secar los cafés.  La primera opción es una máquina de Alemania (foto abajo a la izquerda).  Los cafés dan vueltas mientras calor entra la máquina.  La segunda opción es una caja donde calor entra en el piso de la caja, y trabajadores caminan en los cafés para mezclar.  La ultima opción es solamente poner los cafés afuera para secar (foto abajo a la derecha), pero si hay lluvia necesitan mover los cafés para que los no son mojados.  La máquina de Alemania es mejor porque los cafés secan mas rapido de las otra opciónes y no necesita mas trabajo.  La segunda opción (como la caja) es muy mal por la salud de los trabajadores y ellos siempre estan enferma.  La ultima opción (los cafés afuera) es muy lento.  Yo pregunté ‘¿porque ellos no construyen una otra máquina de Alemania?’   Mi maestro respondó ‘es una buen pregunta’ y el dijo posiblemente porque los dueños no lo queren y quieren trabajos por mas personas.

The final dried coffee beans of the best quality are the whitest ones, as shown below.  Almost all of the good coffee coming from Guatemalan coffee plantations are exported. 

La ultima paso de los cafés mejores es en la foto abajo donde son muy blancos.  La mayoria de los cafés mejores venden en otra paises.

Technology distribution models

It was interesting to learn about the different distribution models for the stoves in Guatemala.  Recall that the Spanish school developed a very cheap and easy safe stove that could be provided to families for little to no cost.  The company I volunteered with had a different model, of selling the stove to families, and any family could purchase one, and while the costs were on the higher end, the families could pay in payment plans where each month their fee was estimated to be equal to the amount that they would typically pay for extra wood for a non-fuel-efficient stove.

Es muy interesante aprender sobre las diferente modelos de distribución por las estufas en Guatemala.  La estufa de la escuela tenía una deseño por la estufas que es muy barrato y facil.  Entonces las familias podían recebir las estufas por menos o nada cuesta.  Las estufas de la compania distribieron con un otra modelo.  La compania vendía estas estufas a alguien familia.  La cuesta era mas de un tradicional estufa, pero las familias podía pagar un poco cada mes, y la cuesta por una mes es la misma de la cuesta por la leña por un estufa tradiciónal. 

Neither of these models are better.  They each have tradeoffs and serve different markets, and having both types of models helped ensure a larger population of Guatemalans with safe stoves.  Sustainable distribution models for safe stoves, and other types of technologies for improving quality of life in rural areas, are sometime more difficult that the engineering of the technologies, though often these concepts are intertwined. 

No modelo es major.  Cada modelo tiene un diferent propósito y cada modelo tiene intercambios.  Mas modelos es mejor por los Guatemaltecos porque mas familias reciben estufas.  Modelos de distribución que son sostenible de estufas y otra tipos de tecnologia es una problema y a menudo haciendo un bien modelo es mas dificil que la deseño de ingenieria, pero ambos son conectado. 

When I was talking with my Spanish teacher in Guatemala about energy in his country, I asked about why wind and solar energy was so rare.  His answer was that these technologies are very expensive. 

Cuando yo hablaba con my maestro de español sobre energía en Guatemala, lo pregunté porque no hay mucho energía de viento y sol.  La repuesta era que estes tecnologias son muy caro. 

WindAid, the organization in Peru that I am currently working with, has come up with several models for distributing wind energy to communities without power.  WindAid has a basic volunteer program that includes training in manufacturing their wind turbines, and almost half of the volunteer fees goes to pay for a wind turbines for a home or community area without power in Peru, and the people without power get these wind turbines at no charge.  During my first week in Peru, I helped install one of these 500 W wind turbines at a beach restaurant in Sichura, Peru. 

This restaurant was in a beach area that is popular with the locals, and before the turbine was installed, this restaurant and all others in the vicinity had to rely on batteries to use lights, radios, etc.  The wind turbine will now allow the owner to keep his restaurant open later at night with music and lights. 

This type of social entrepreneurship where volunteers provide much of the funds for these technology projects has the potential to work well on a small scale.  But WindAid has also come up with other methods to get wind turbines out to communities who need power.  This beach restaurant was chosen to receive a wind turbine in part, I think, because it would be a great spot for publicity of the organization and their wind turbines.  We posted fliers explaining wind energy at the restaurant, and we did indeed get a lot of curious beach goers come by and ask questions about it.  The flyers encouraged people to contact WindAid, and I assume will lead to more purchases of wind turbines, more communities inquiring about obtaining a turbine, and hopefully more financial support into the program. 

WindAid does also sell wind turbines, so clean energy (energía limpia) can go out to more locations.  Furthermore, the organization is also working with another organization to provide the wind turbines for free, and then after the community uses it for a month or so to see how it can help improve the quality of life by enabling children to study after dark, people to charge cell phones, etc. a device will be installed to charge the users for each kW-hr they use at a very low cost.  They theory is that after enough time, the cost of the wind turbine will be paid for, and thus this becomes a sustainable distribution system of wind turbines.

Energy in Peru

I’m still in the process of analyzing all of the stove data I collected, but will have to do that in Peru since I’ve moved on to additional interesting projects. 

I got picked up by this vehicle in Piura, Peru where I will be helping install a 500 W wind turbine (turbina eólica) in communities without power.  What’s neat too is that I found out this vehicle runs on natural gas as well as gasoline.  In fact, many vehicles in Peru are natural-gas-gasoline hybrids, and in the big cities, it’s very easy to find natural gas for purchase which is much cheaper than gasoline, and the gasoline tank can still be used in the mountains.

Our first stop, after picking up a piece of wood (madera) to mount the turbine on to, was to a community where one of these 500 W turbines had already been installed.  These turbines are about the perfect size for a single multi-person household without electricity from the grid, and these turbines can generate enough electricity to power lights at night and possibly charge cell phones and sometime even a television.  Some of these houses also have solar panels that are primarily used for charging cell phones, though the solar panels have a high upkeep since they get dusty frequently, so that's why the wind energy is great to have (las panales de sol necesitan limpiar con mas frecuencia, es la razon que energía de viento es mejor).  

This particular house we visited was having problems of the turbine not reaching its full potential, most likely due to the fact that there were trees in front causing turbulence (los arboles en frente de la turbina son una problema).  We debated for a while whether the best solution would be to raise the height of the turbine since wind speed picks up with altitude, though this would create more problems with vibrations, or to move the turbine to another location.  We even began to think about what type of cheap tool we could use to measure the vibration force, maybe a smart phone app of some sort (pensamos lo que herrmienta barrata podemos usar para medir los vibraciónes, posible una aplicación de telefonos inteligentes).  Another suggestion was put out to cut down the trees (una otra opción fue cortar los arboles).  The final decision was to move the turbine and make it taller (la ultima decisión fue cambiar el lugar y hacer mas alto).  Since the sun was about to go down when we arrived, the family was planning to get this started and maybe finished, and we would return another day if needed (la familia empezará este proyecto y talvez terminará tambien, y nosotros volveremos si es necesario).

Mas a venir sobre mi primera viaje de instalación en Peru, y terminaré las estufas tambien.  (more to come about my first installation trip in Peru, and I will finish the stoves too).