Passive solar home design
The steps of the project:
We started of this project by building a solar water heater. The purpose of this assignment was to learn about the thermodynamics of water. We used a variety of materials to successfully assemble a water heater. After leaving it in the sun for 20 minutes, we recorded the change of temperature.
Our water temperature went up a total of four degrees. After, we got creative and decided to try to make a self circulating water heater. We attached the tubes to each other and used the water pressure to keep the water circulating. It worked for about two minutes. We found that making a tinfoil "bowl" around the box would reflect more of the light and heat into to the pipes. Unfortunately, the flaps of this bowl had to be painstakingly aligned to make sure that the light and heat was not reflected away from the pipe.
The next project we did was the day lighting technique project. We were tasked to design a 1000 square foot building that utilized various daylighting techniques. Our building included light shelves as well as clearstory windows. The rooms were also oriented for the optimal amount of sunlight. Our building was one of the more efficient designs and only would use 2.015 kw/d when the day lighting techniques were put in place.
Next, we were to use the information we learned from the first labs and design a passive solar home.
Location: After careful consideration, we decided to place our building behind the cafeteria along Novato Blvd. We chose this location because there is minimal tree shade and the building could be permanent in that location.
Size: Our building would be 10 feet by 12 feet or 120 square feet
Key Features:
Our water temperature went up a total of four degrees. After, we got creative and decided to try to make a self circulating water heater. We attached the tubes to each other and used the water pressure to keep the water circulating. It worked for about two minutes. We found that making a tinfoil "bowl" around the box would reflect more of the light and heat into to the pipes. Unfortunately, the flaps of this bowl had to be painstakingly aligned to make sure that the light and heat was not reflected away from the pipe.
The next project we did was the day lighting technique project. We were tasked to design a 1000 square foot building that utilized various daylighting techniques. Our building included light shelves as well as clearstory windows. The rooms were also oriented for the optimal amount of sunlight. Our building was one of the more efficient designs and only would use 2.015 kw/d when the day lighting techniques were put in place.
Next, we were to use the information we learned from the first labs and design a passive solar home.
Location: After careful consideration, we decided to place our building behind the cafeteria along Novato Blvd. We chose this location because there is minimal tree shade and the building could be permanent in that location.
Size: Our building would be 10 feet by 12 feet or 120 square feet
Key Features:
- Day lighting techniques such as celestial windows to let in morning light
- Dark hardwood floor to retain heat longer
- Strongly reinforced walls and double paned windows
- Fiberglass insulation to keep the heat in
- White walls to reflect light, heat, and make the room seem larger
- Dark brown outer walls to absorb more heat
- A slanted thicker roof to retain more heat and gutter to repel rainfall
- Concrete foundation
Budget
Our budget was a big part of this project. We were only allotted $5,000 to spend on the whole building. After totaling up all of the expenses, we came to a total of $4,328.90. The money left over would be used to furnish the building or be put into the STEM funds.
Our model
I am very proud of our model. We used various craft materials to symbolize the real life materials. Popsicle sticks were used as two-by-fours and cotton balls were used as our fiber glass insulation. We used cardboard as our drywall and more popsicle sticks that were stained dark brown as our dark hardwood floor.
Concepts Used
Physics Concepts: Throughout our project, we looked into many different physics concepts in order to fully understand the meaning and importance of energy efficiency.
Conduction - transfer of heat through a material (when a pot conducts heat from the stove to the food) Convection - transfer of heat through a fluid (convection currents in the ocean or in the earth's core) Radiation - energy transmitted as rays, waves, or particles (energy from the sun) Heat - a form of energy (Q) Thermal Conductivity - Heat travels from places of lower pressure to higher pressure, or from hot places to colder places. This is why "coldness" is simply the absence of heat. The reason why your hand feels cold after touching ice is because the heat has left your hand and traveled into the ice, melting it. However, touching carpet doesn't have the same effect because it is not a good conductor, and therefore doesn't take as much heat from your hand. Fluids - a substance, liquid or gas, that is capable of flowing and that changes its shape to fit its container Pressure - the exertion of force upon a surface by an object, fluid, etc. Buoyancy - ability to float or rise in a fluid. An object must have a density less than the fluid it's in if it wants to have any chance of floating. Water, for example, has a density of 1. Anything with less density than 1 therefore floats -- like a cork, or paper boat. Objects with a density greater than one, like a nail, sink. However, there are exceptions to this law, and that is by filling the object with lots of air. That's how ships float; they have lots of air pockets in order to keep the ship afloat. Gases - a substance possessing perfect molecular mobility and the property of indefinite expansion, as opposed to a solid or liquid. Gases make up the air around us, which is measured by an instrument called a barometer. Gases have high molecular action, and therefore gases with higher temperatures have lower pressure because the same atoms are just taking up more space, and therefore aren't as rigid and able to bear down pressure. Laws of Thermodynamics - There are four main laws of thermodynamics; the 0th, 1st, 2nd, and 3rd. The 0th law explains temperature, and states that if two systems are in thermal equilibrium with a third system, they are also in equilibrium with each other. (Transitive Property: if a = b, b = c, then a = c.) The 1st law explains conservation of energy, stating that energy is neither created nor destroyed, and that heat is a form of energy. The 2nd law is about how entropy increases; as time passes, energy gets more and more "messy and unstable." For example, the sun gives of significant quantities of energy, but as it does so, it becomes more unstable until it will eventually explode. The 3rd law simply states that temperature can never get down to absolute zero. The idea of absolutely no molecular action is merely theoretical, as heat always exists, even if it's very very slight. Specific Heat - a physical property of matter that states the heat capacity of a certain object. Objects with higher numbers take longer to heat up, but also take longer to cool down. Objects with low specific heat capacities heat up quickly, but also lose that heat relatively fast as well. Water is an example of a fluid with a particularly high specific heat of 1. This explains why we use water to cook. It heats up after a while and keeps that temperature for a long enough time to cook through our food. It also explains why coastal cities have milder winters; San Francisco has a warmer winter than a place like Sacramento. This is because the heat from the summer is still somewhat retained in the water surrounding the city and keeps the area from freezing over.
Reflection
I liked this project. I worked with Bronte Hoefer, Austin Marshall, and Eryk Lewandowski. Our group worked very well together, we were very compatible. One thing we did well on was delegating the tasks equally. Eryk was in charge of the shopping list and budget. Austin did the blue prints and gathered location data. Bronte and I were in charge of the model and the presentation. We also all helped out when needed.
However, I would have changed some things. We should have prepared for more questions. Our presentation was well prepared but not the questions. When asked a question, there would often be an awkwardly long pause before we figured out which one of use was going to answer. We definitely could have anticipated more questions and delegated who would answer questions regarding various subjects.
However, I would have changed some things. We should have prepared for more questions. Our presentation was well prepared but not the questions. When asked a question, there would often be an awkwardly long pause before we figured out which one of use was going to answer. We definitely could have anticipated more questions and delegated who would answer questions regarding various subjects.