Harnessing renewable energy sources is crucial for supporting the energy demands of modern society. The IEA calculated that global energy usage increased by 10% from 1990 to 2008, and the number is expected to rise in the coming decades. At the same time, our currently predominant sources of energy pose serious threats to the environment and human health. The burning of fossil fuels—natural gas, coal, and oil—releases harmful greenhouse gases into the atmosphere, contributes to ocean acidification, and creates pollution with both economic and social costs.
Solar power is a particularly promising solution to the world's energy needs. The Earth annually absorbs nearly 4 million exajoules of solar energy, and it would require less than an hour of this total energy to power mankind for an entire year.
There are many technologies to capture and convert the sun's energy. My research team has been experimenting with DSSCs: dye-sensitized solar cells. They differ from traditional photovoltaic (PV) cells that currently dominate the solar cell market, and DSSCs have their own advantages and disadvantages. The tradeoffs will be discussed later in this guide. (View the ground-breaking Smestad and Grätzel paper "Demonstrating Electron Transfer & Nanotechnology: A Natural Dye-Sensitized Nano-Crystalline Energy Converter" to learn more about the technology).
I will be explaining how dye-sensitized solar cells are assembled, and how they can power an electronic gadget---in this case, a calculator.
Step 1: Gather Your Materials
Here are the necessary materials for this project:
- Fluoride-doped tin dioxide conductive glass (≥2 plates)
A source of organic dye (ex: raspberries)
- Titanium Dioxide Paste
- Acetic Acid
- Glass Stirring Rod
- Scotch Tape
- Graphite Pencil
- Liquid Electrolyte Solution
- Binder Clips
- A Solar-powered Calculator (You will be removing the stock PV solar cell and replace it with your assembled DSSC)
- Soldering Equipment
- A Multimeter or Vernier Lab Quest (with Voltage & Current Probe(s))
- Tungsten Halogen Lamp
- Testing Apparatus