Residential and commercial buildings consume an enormous amount of electricity. Most of it goes toward running the A/C, appliances, computers, lighting, etc. If the goal is achieving environmental sustainability, there are two paths forward: 1) increasing the efficiency of whatever needs power inside the building (or more efficient power management), or 2) deriving power from a sustainable energy source.
This project focused on the latter method by capturing the energy of sunlight incident on the facade of buildings. To provide some rough numbers at why this might be a good idea:
- The average warehouse roof (17,400 ft2 receives over 2 million kWh/yr of sunlight (enough to power over 400 households)
- A 20-story building’s south face (10,000 ft2 gets 600,000 kWh/yr of sunlight (enough power for 100 households)
Our goal was to make use of the high surface area of glass facades on many commercial buildings by creating transparent windows that redirected light onto conventional solar cells for energy generation. In the ideal case, every photon of light that didn’t pass through the window (some amount of light needs to pass through to achieve transparency) would be redirected onto a solar cell.
Prototype 1 – Patterned Luminescent Solar Concentrator
The first prototype was built during MIT MADMEC (Making and Designing Materials Engineering Contest) 2011 with a group that included other graduate students Rishabh Jain, Tim Milakovich, Geraldine Paulus, Ardemis Boghossian and myself. The novel concept was a luminescent solar concentrator (LSC) that took advantage of a patterned array of dye spots.
Prototype 2 – Layered Prismatic Concentrator