Solar Energy

Investigations 3 & 4: Solar Water Heaters

Solar Houses

Investigation 3 – Solar Water Heaters

Main Ideas/Content• Black plastic absorbs the Sun’s energy, which

it transfers to the water by contact.• White plastic reflects the Sun’s energy.• A cover keeps the heat inside the container.• Solar water heaters in houses today work by:

1. Placing solar collectors filled with water on the roof to absorb the sun’s rays

2. Sun-heated water is piped down into a storage tank in the house.

• Larger collector surface areas cause the water to heat up more and faster.

• Dr. Maria Telkes was the world’s most famous female inventor in the world of solar energy. – Invented model of a solar oven– Also helped design and build a solar house

Investigation 3

Vocabulary Words– Absorb – to take up, soak in, or capture.– Reflect– to bounce back.– Solar Collector – a material used to capture solar

energy in a water heater or other device.– Solar Cells– devices used to transform solar

energy into electricity.– Fossil Fuels – natural gas, oil, or coal, that is taken

from the Earth.

Investigation 3

• Space heating is the transfer of heat energy to the air in an enclosed space.

• The orientation of a solar house to the Sun affects how warm it gets inside.– Houses facing the Sun get warmer much faster

• Light comes in through the glass• The surface absorbs the light and heats up• Heat can’t escape through the glass

– This is similar to how a greenhouse or parked car with the windows up works

• Houses with dark interiors heat up more and stay warmer longer than houses with light interiors.

Investigation 4 – Solar Houses

Investigation 4

• Different methods of design and decorating help warm homes and keep them cool (i.e., adding insulation, curtains, etc.)

• Advantages to solar energy: renewable resource, pollution-free

• Disadvantages: very expensive equipment, works best when Sun is shining, takes longer to heat water, not as many companies around

• Wind power is also an important source of renewable energy for our future.

Vocabulary Words– Orientation – the direction of an object in relation

to another object. To orient something is to set it up in a definite direction.

– Passive solar energy – system that provides heating (or cooling) WITHOUT any mechanical or electrical devices.

– Active solar energy - system that provides heating (or cooling) WITH the assistance of mechanical or electrical devices to move heat around.

Investigation 4

Investigation 4

Active Solar Energy Systems