Hello, Physics forum community.I have a project for an intro to engineering class in which I must design a system to solve an environmental problem. This class is only an introduction so I'm not sure how detailed and specific our work has to be. I must have been feeling very sci-fi at the time because I thought of doing a project on underground living to deal with urban overpopulation. Since then I have done some research and came up with a couple of project ideas centered around this theme. I'd love to get your opinions on which project idea sounds better from an academic perspective. 1. The problem statement, all variables and given/known data Idea one: Large scale underground living. There are obviously numerous factors to consider due to it's scale but I thought I could focus on the problem of creating a structure that allows a maximum amount of natural light to reach the underground floors without making an unreasonably large hole on the surface. Why? because light makes the idea of underground living more pleasant even if people are in no way confined to the ground. This is more a solution to the urban overpopulation problem. Idea two: small scale/family underground - ish living. This is something that already exists and the house would not be completely buried. The problem with these houses is that they are expensive to build because the walls need to be strong and insulated. The idea for this project will be centered around finding a more cost effective material or stable structure to build these houses. This type of underground living can be very environment friendly and even saves expense especially in the long run in cold and hot places because the earth naturally keeps the temperature constant. 2. Relevant equations For the first idea I would be looking for some structural ideas and evaluate their merits through a ratio that compares the area of living space provided to the area of hole on surface to the area that sunlight reaches underground. There are other things that I could take into consideration like sunlight intensity and angle during different times of the day and year which, should I? 3. The attempt at a solution That is all.