My high school is planning on building a green wall, and my class is to design different proposals for the construction of it. In addition to the green wall, the school is going to install solar panels to generate electricity for the power grid.
A green wall is basically a wall of plants. The purpose of a green wall (environmentally) is to provide insulation for the inner walls of the school. In addition, growing more plants will increase the biodiversity (to increase the amount of bees, butterflies and more) and also rid of some carbon dioxide. Green walls can provide food for the Food and Nutrition courses in my school through growing eatable plants. The plants grown on the green wall can also absorb the rainwater to prevent the flooding of sewers. Green walls are also used to boost up aesthetic appeal.
Our job (as students) is to create a design brief for the wall, provide a bill of materials and their specifications, decide different locations for where to place the green wall, create a design to be used for the green wall (including water system, structure of wall and more), find stakeholders for the project, propose plants to be used for the wall and to provide a construction plan. My group used this neat video on YouTube to place the plants to the wall: http://www.youtube.com/watch?v=DtzqRv3WYXQ
As I was working on this assignment, I’ve learned about the challenges and stress it takes to build an actual structure that will be staying on the school. Unlike our other school projects; this project has a specific budget, a specific area/space that the green wall will be placed on, and other limitations. While planning designs for this assignment, I felt a little restrained to what we were capable of doing. Through this “Green Wall” assignment, I have experienced a little of what it is like to be an architect and to design real structures for buildings. I can’t say I like it very much.
I’m pretty sure everyone knows what solar panels are by now. They’re panels used to convert solar energy/radiation into electrical energy for use. There are many different types of solar panels; I will be explaining the most commonly used one: the crystalline silicon solar panels.
First, a solar panel contains many layers. The outer layers are made from glass or plastic to protect the other layers inside of it. It may contain UV enhancement film to increase the UV radiation intensities from the sun (for more energy). Within the glass, there are conductive layer(s) and photovoltaic cells. Usually, the photovoltaic cells are made from silicon. The silicon contains two layers made from two other elements; one layer with too many electrons and one layer that has too little electrons.
As said before, solar panels contain a bunch of semiconductors, called photovoltaic cells or solar cells, which convert sunlight to electricity. When light particles (called photons) hit the surface of the panels, the layer with too many electrons loses some of its electrons. The loose electrons are then released as an electric current which is sent through the layer with too little electrons to an external load to store the energy. The electrons then return to the layer with too many electrons (as it’s now missing electrons) and then the process continues as the external load continues to store energy.
On average, crystalline silicon solar panels are only capable of converting 12-20% of the solar radiation to electrical energy (the first solar panels were only capable of converting 3% of solar radiation). The process of converting electrical energy is too slow and expensive, which is possibly the reason in which why solar panels are used less compared to other forms of energy generation such as Pico-Hydro and wind-turbine generators.
This post talks about the manufacturing of glass. First, glass is made from a bunch of different things. Silicon, lime, aluminum oxide, magnesium oxide and sodium carbonate are required in the manufacturing of glass; so sand, flint, limestone, soda (which is sodium carbonate), gold, nickel and other things are added in the combination process. The method for making flat glass is called the float glass process.
The float glass process involves having a large furnace that mixes all the materials (listed above) together into an oven that heats up to 1600 degrees Celsius. In order to colour the glass, different metals are added to the batch. Iron makes green. Manganese shows purple. There’s a lot more that are shown in this website: http://www.tynant.com/main.aspx?pID=39-0
The heated up mixture is placed into a tin bath (a tub of molten tin) in order to make sure that the glass can be seen through and to make sure that the glass is nice and smooth. The glass from the tin bath is removed with some rollers. The speed of the rollers will determine the thickness of the glass. After all of that, the glass is cooled, cut and then sent for manufacturing.
There’s another way of forming glass called the glassblowing method, which is used to make vases and/or bottles and many other things. It involves blowing into molten glass with a long tube to make a bubble-like shape. Some glass bottles are still made using this method; however a lot of them are mass produced using machinery sending compressed air into the bottles instead of someone blowing through them. Some bottles are plainly carved from a piece of glass.
For the site plan of the cabin, I used a large board of wood with a big piece of foam that I got from my dad from his workplace. The foam was covered with some green cloth that I found around my house. The intention of the foam was to let me pluck in small trees into the foam, as it was very difficult to glue/tape on the tiny trees. A river was made from an Aeropostal bag (as I couldn’t find anything blue to put on), and the wind-turbine generator was made from paper/Bristol board.
The following explains about how I made the insides of my model:
For the windows, I cut out small sheets of plastic and then taped them within the inner walls of the cabin with duct tape. I then covered the inner walls with white paper, which helped hide the duct tape and the cardboard. For other parts of the cabin (including the rocket stove and the bathroom) I pieced together some cardboard using a glue gun and then covered them with white paper to hide the zig-zag patterns of the cardboard. For the doors and the ladder, I used some leftover balsa wood from my classmates and then glued them on wherever I needed them. For the foundation, I used four small pieces of wood to elevate the cabin.
Here are some more pictures of the cabin:
I’ve finally finished my final cabin model! The cabin turned out better than I expected. Here’s a brief summary of how the construction went:
Since I used cardboard to make the walls of my cabin, I had some problems painting it with watercolours, as the paint wasn’t very visible (I could still see the Cheerios logo in the background from where I got the box from). As a result, I decided to cover the cardboard with white paper and then paint over it. This, however, caused to the paper to get really soggy and sometimes rip, so I had to tear off the white paper. Now that I think about it; this idea could have worked a lot better if I were to just use a thicker type of paper – one used especially for water colouring, or if I used a different kind of paint, like the paint used to paint walls. Instead, I thought of a much worse idea by covering the cardboard with drywall compound to help make the paint stick on it more easily (The actual use of drywall compound is to stick sheets of drywall together like a type of plaster or mud). In the end, the drywall compound caused the cardboard walls to curve slightly once it dried. Also, it caused some of the drywall to peel off and/or crack; thus revealing the cardboard within the cabin (in which I had to fix after); although this was probably due to my limited skills in using drywall compound, as the drywall compound appeared really bumpy in texture and had an uneven coating. When I glued every piece together, the four outer walls looked better than I expected (what I expected was having large ovular gaps between each corner in which the walls were glued together; however the walls stayed together appropriately due to the strength of the glue from the glue gun). All in all, I would advise planning your steps beforehand using project management to reduce the workload to yourself and to increase efficiency while working. Here’s a document I found on Google about the basis of Project Management: http://www.personal.psu.edu/mum28/blogs/Mairead/Project%20Management%20Steps.pdf
For the roof of the cabin, I also used cardboard. I cut out the pieces of the cardboard according to the measurements made on AutoCad, and then pieced them together. I then covered the roof with cut out strips of black Bristol board to make the shingles look more realistic. I then added shish-kabob skewers within the roof to act as roof trusses (I don’t have any pictures of that now, but I’ll include them in my next post).
As for what I learned about the process of model-building; I find it quite relaxing and fun to do. Looking at my final product, I feel as if though I’ve accomplished a great goal in my life. Modelling the building allowed me to gain a better idea about what it was that I was trying to build. While constructing the cabin, I’ve discovered several problems about my design (such as having a roof that was too small to fit a rain barrel within it); hence through modelling I was able to improve my design aesthetically and structurally. In addition, I found it frustrating to work with such small pieces in the cabin; so I guess model-building also requires a lot of patience and diligence.
Here’s a picture of the cabin:
After sketching the drawings on paper, I had to show my ideas on AutoCad in order to get the proper measurements for my design. This is done so that the construction of the model will be more precise/easier to make. Of course, the measurements are to scale to show inches and feet- architectural measurements.
For the drawings on AutoCad, I need to show everything from a birds-eye view; showing the first and second floors of my cabin. Also, elevations are required to show the side/front of the cabin. In addition, I will include a site plan to show what’s happening around my cabin (to include a river, some rocks, my pico-hydro and wind turbine generators and more).
I didn’t include many hatches to the AutoCad drawing (in AutoCad, hatching is used to add a texture/design to a closed shape). This was so that I wouldn’t get confused/distracted by my design. This also makes my design look really simple; which is good in that it gives me a better understanding of what I’m building, but bad in that the AutoCad design itself looks unappealing.
Going back to my “Functions of a Cabin (and any other house)” post, now I need to design a rustic-looking cabin that includes all the functions that I’ve talked about (volumetric space design, energy systems, water systems, waste management systems and climate control system). To “design” means that I just have to draw out the cabin from different views (inner, outer, site plan…) and write out a bill of materials for all the things that I’m using for the cabin, including a rocket stove, which was explained in my “Rocket Stove to the Sky” post. I’ve already done all of that, though, and I will be posting pictures later of some of my drawings/bill of materials. NOW, I have to make a model of my cabin that I’ve been designing.
For the cabin, I chose to use cardboard to make all my outer/inner walls (although balsa wood would have worked much better) I got the cardboard from No Frills for free, and I’ve already covered most of it with white printing paper to be painted over, later on. My foundation is just a large wooden plank and my site plan (including trees and a river) consists of items that I got from dollar shop (Christmas decorations). I haven’t completed the cabin yet, but I’ll be sure to post pictures of it when I’m done.
Anyways, here are some pictures of other people’s professional-looking models:
Rocket Stoves (rocket mass heaters) are heaters; they heat the house. They’re “super efficient furnaces.”
FURNACES INFORMATION: The efficiency of furnaces is measured in AFUE, which is a number that shows the percentage in efficiency (A greater AFUE results in a greater efficiency). High efficiency furnaces range from 90 to 97%, while low efficiency furnaces range from 80% and less.
90-97% is already pretty efficient for a furnace, so how can rocket stoves beat that? I don’t even know. The efficiency of rocket stoves haven’t been professionally analyzed yet, so there’s not really a specific number that shows it; not in the AFUE (if someone can tell me otherwise, please do! I’ve been looking for an answer from many sites now, but I can’t seem to find a proper answer). Guaranteed however, rocket stoves are a very efficient way to heat up one’s house (efficient as in the amount of fuel – wood – put in will bring you a lot of heat, and for a long time too – which is up to 4 days).
In the picture on the right: Wood and oxygen go in on one side to be burned in the burn chamber and then transferred into the steel drum. The steel drum brings out some of the heat directly out into the house for immediate heating, while the rest of the heat is transferred through a long, airtight duct to keep the heat circulating around the house to have constant heating. The duct is usually covered with clay, mud, stone and many other materials and then covered with a ceramic spray to keep everything together. This clump of clay, mud and stone (and many more materials) that covers the duct can be used a furniture; a couch; a bed; a table; anything.
This is the only website I’ve seen so far that sells rocket mass heaters: