Solar Powered Science Projects
- Batteries power all kinds of portable electric and electronic devices. A solar-powered battery charger lets you accumulate electricity over time to produce larger, more useful amounts of energy. To produce electricity from sunlight on a small scale, you'll want to use photovoltaic cells, commonly called solar cells. Each cell puts out between 1/2 to 5 volts at a few milliamps of current. A solar battery charger will have several solar cells wired together, a regulation circuit to manage the current going to the battery and the battery itself.
- Many people in sun-drenched parts of the world have taken advantage of low-cost solar cookers. One design involves using a parabolic mirror to focus sunlight onto a small area, raising the temperature a few hundred degrees. You can use this to quickly broil small food items. When you need to cook larger amounts of food, a box-style solar oven collects and accumulates heat inside its walls, gradually raising its temperature for crock-pot style cooking.
- Homes can use solar power in many different ways. The familiar solar roof panels produce electricity or heat water for domestic use. Architects can also design the walls of the house to efficiently absorb sunlight and circulate the warm air inside. For a project, build a miniature house that uses passive solar heating, measure the temperature inside the rooms and see which architectural designs work best.
- Water is a useful medium for distributing heat energy from a power source to where you need it. Many buildings now use water heated by sunlight for domestic hot water, to heat pools and for space heating. You can construct a small-scale solar water heater to demonstrate how this works. Basically, the design involves a length of copper pipe, bent into an S-shape to save space and painted black to absorb heat from sunlight. Cold water flows through the pipe and absorbs heat. The pipe must be metal in order to transfer heat efficiently to the water. The water flows into an insulated storage tank, where it can stay warm for a while until you use it. Measure and chart the water's temperature over a few hours.
