Week 9

After a few quiet weeks, we have lots to report! We’ve spent the last few weeks working on several small projects to incorporate into our new structure and as of today, most of them are complete! The main four components we’ve installed are a passive cooling “air conditioning” unit in the window, a two-tiered roof, a solar chimney, and a ventilated block near the bottom of the structure. Below are pictures and descriptions of each element.

In the bottom right corner, you can see our ventilated block. The team is still working on a few different molds to incorporate ventilation into the blocks, however this one did not require a new mold. We simply turned the block and added removable screen inserts to the holes. The benefits of this model are that it doesn’t require a new mold, the openings allow for cool air to enter the building, and the screens keep the bugs out and can be easily replaced if damaged. A practical issue with this method would be that turning the blocks might get in the way of reinforcing the structures with rebar which they often do in Senegal.

Above is the new two-tiered “cool roof” we’ve designed and installed. The design is pretty simple; there are two layers of corrugated steel with about 3 inches of open space between them. As the sun hits the top layer, the steel absorbs the heat, but instead of being absorbed into the house, it is then reflected by the inner steel layer and then the natural breeze flowing between the two layers pushes the hot air out before reaching the inside of the house. This seems like a viable option for the Senegalese people because it uses the same materials they typically use for roofs, so cost, aesthetics, and availability should not pose issues. Already we can see that it’s working as the top layer’s temperature is about 10-20 degrees hotter than the inner layer.

This is our passive cooling “air conditioner.” The idea behind this system is that there is a pot filled with cool water inside the window unit and the heat causes the water to evaporate which cools the air surrounding it. As a natural breeze comes through the unit, the cooled air will enter the home. While cost and availability of materials shouldn’t be an issue, one thing we might need to consider is the risks of having standing water in their homes as this provides the perfect breeding grounds for mosquitoes. To prevent this from happening, we could build a screen door of some kind on the interior to prevent bugs getting in from either side.

Our solar chimney builds off the simple principle that heat rises. By painting the chimney black, it will absorb more heat which causes the air inside to heat up and rise. As the hot air inside the chimney rises and exits, it continues to pull the hot air from the inside of the building up and out. This system works well with the ventilated blocks at the bottom because it creates a flow of cool air entering and hot air exiting.

Just after one day we are noticing huge changes inside the structure. In the past few weeks, we have typically been finding the inside temperature to be the same or only one or two degrees cooler than the outside. However, with all our new components, we are finding the inside of the house to be consistently five to ten degrees cooler than the surroundings!

Week 6

Our model home is officially done! We finished constructing the roof early last week and added a curtain to the door and louvres to the window on Friday. We have two thermometers that we will check periodically throughout the day to keep track of the temperature and humidity so that we will be able to compare our results to altered future versions of our structure.

We have left a few of the bricks unmortared and the roof is easily removable so that we can apply and test any new components we design into the existing structure without difficulty. Our group has kind of naturally split into groups so that some of us can work on the roof elements and others can work on alterations to the blocks and their configuration.

After some of the team had taken their vacation week, we all reconvened in New York City on Wednesday for a whirlwind day of taking in culture, exploring, and learning. We started the day at the new SUNY Downstate campus medical building, where we took a tour of the building under construction. It was really interesting to see what goes on behind the caution tape at a construction site and to get a close look at all the internal steps in the building process. 
After our tour, we visited the Ennead architecture firm office. They are the firm working on the SUNY building, so we were able to talk a little more about that building as well as other ongoing projects they’re working on. While it was cool to see the SUNY building, our main reason for visiting the office was to talk with one of the partners who had worked on a project building a school and community space in rural Zambia. She gave us a really nice presentation on the project and a lot of good insight on all the things that go into making a project like that possible. About halfway through our own project, this provided exactly the inspiration we needed to keep us motivated and excited. 
Next we headed to Little Senegal where we had a delicious, authentic meal and explored some of the local shops. It was nice to reminisce about our time in Senegal and to experience a little taste of the culture for our team members who were not on the trip. It was a great day packed with lots of fun and interesting activities. Today is our first day with the entire team here and we are feeling inspired and ready to keep working!