Step 1 - Generative Design Framework
DESIGN 1: My first design idea was to create a graph that would use controlled variables such as square footage and r-value, and independent variables such as length/width/height to show options that would maximize natural light (lowering energy cost toward lighting) and minimize the amount of central cooling needed (minimizing energy cost toward temperature control). This ended up being much more complicated than I had expected and found that the tradeoffs seemed arbitrary. It was entirely about height versus length which would be restricted anyways by lot size.
DESIGN 2: My second design was to take controlled variables such as height and square footage and dependent variables such as length, width, and shape, to show an evaluator of the optimal shape of the building to minimize structural beams and columns needed while keeping the building material costs low. In the end, the tradeoff ended up being that with minimal beams and columns needed, more walls and materials for the building were needed, so the cost wasn’t actually optimized by minimizing beams and columns. Also, the physics needed was beyond my skills.
DESIGN 3: My last design (which is the one I went with) had to do with energy, such as the first option, and I decided to try and maximize the amount of energy gained through solar roof panels while minimizing energy lost through the roof and walls. The tradeoff ended up being that the building was short and had a large area, sort of like a warehouse.
Step 2 - Generative Design Study
- I ended up adding more evaluators to my design such as the cost of roof/wall materials as well as the total energy lost through the roof/walls per square foot (similar to EUI, just not taking into account the total collective energy use of the building as that would vary depending on what the building’s use is). From here, I decided to compare the tradeoff of how the cost is affected by choosing a more efficient solar roof energy.
- Calculating the cost of materials was quite easy. Using the average cost per square foot of wall and roof materials, I created a code block that would multiply each by their respective surface areas. Calculating the amount of energy lost per square foot was easy as well, as I took the total energy lost in the building and divided it by the total floor area. Calculating the energy lost through the roof and walls was done by taking the area of the walls or floor, multiplying it by delta T (the change in temperature from inside to outside), and dividing it by the r-value of each building part. From there, I added the energy lost through the roof to the energy lost through the walls to create the total energy lost. The total solar roof energy was calculated by multiplying the roof area by the roof energy value.
- Because each of these evaluators was calculated using simple math functions, they stay consistent through all sets of variables being changed.
Step 3 - Generative Design Study Results
This scatterplot shows the relationship between the total cost of the roof and wall materials and solar roof energy. Obviously, we want to minimize the cost and maximize solar roof energy. Unsurprisingly, there seems to be a pretty linear relationship between the two. Therefore the tradeoff shown is that as you maximize solar roof energy, the cost of building materials grows as well. I believe that in this case, choosing somewhere in the middle to the upper end of cost is the best solution. With more solar roof energy, less total energy is being lost. Therefore, over time, you will save money. If you put up more money upfront, you will save more later on. Choosing the cheapest option for build creates a more expensive energy bill later on as there is less potential energy being absorbed through solar panels on the roof.
