Teachers need to educate rising generations in the nature and use of solar panels. Children reaching secondary levels should already have a basic understanding of both passive and active solar power. They should have read about solar panels, and they should have hands-on understanding as well. How can we accomplish that?

An experiment with solar panels and clouds will go far toward helping youngsters grasp necessary concepts. This experiment takes little in the way of materials or preparation. You will need a solar building kit, available from Scientifics Online and other science educational suppliers.

Before doing an experiment with solar panels and clouds in class, teachers themselves should work through the entire experiment so they will be able to direct it skillfully.

Experiment with Solar Panels and Clouds

To experiment with solar panels and clouds, you need the following supplies. Groups can share.

* The solar panel and motor from a solar building kit
* 2 pieces of clear plastic, each piece large enough to cover the solar panel
* 1 piece of colored plastic large enough to cover the solar panel
* 1 length of wax paper sufficient to cover the solar panel
* netting material, such as a cargo net, to cover the solar panel
* lightweight “see-through” cloth to cover the solar panel
* 1 light source, preferably sunlight

An experiment with solar panels and clouds should be preceded with a brief discussion of what might be expected to result. Students have a basic understanding of how solar panels can harness and convert the sun’s power. What happens, however, when clouds come between the sunlight and the solar panel? Will that reduce the amount of energy produced? By how much?

After discussion, divide your students into small groups. If you have enough solar building kits, divide into groups of 3 to 5 students.

Begin the experiment with solar panels and clouds by giving each group the following instructions:

1. Connect your solar panel to the motor.

2. Turn the solar panel so it faces the light source as directly as possible.

3. By listening to the motor, you can judge how rapidly energy is being produced. Make a note of how fast it sounds to you.

4. Create a “wispy cloud” by holding one piece of clear plastic between the solar panel and the light source. Listen to the motor again. Note any difference in how fast it is running. Would this amount of cloud cover be likely to affect the efficiency of solar panels?

5. Continue your experiment with solar panels and clouds, changing your “cloud” by placing both pieces of clear plastic together and holding them between the solar panel and light. Note any change in the speed of your motor. Would this type of cloud affect solar panels?

6. Change the “clouds” again by using the colored plastic, then each of the remaining materials in turn. Record carefully every change in the motor’s sound and speed.

When every group has completed the experiment with solar panels and clouds, compare notes. Discuss which materials let more solar power reach the solar panel, and which reduced the amount of solar power.

Have students write their conclusions.

How much is solar power used in a day, a week, a month, and a year? Would you guess that solar power is used very little? Would you believe that solar power might be used more in remote, undeveloped countries or in developed nations?

Pacific Park on the Santa Monica Pier in Santa Monica, California uses solar power to run its Ferris Wheel. The Ferris Wheel is 9 stories tall, can hold up to 120 people, and is powered by a $360,000 PV panel system on sunny days. On cloudy days, it depends on the power grid, but with sunshine, it runs on solar power. That’s an example of solar power usage in a rather unnecessary way.

But how much is solar power used in a day, a week, a month, and a year in necessary applications? Let’s look at it briefly.

Two Kinds of Solar Power Usage

Many times we tend to think of solar power as the power collected by photovoltaic (PV) panels on rooftops. That is one way of using solar power, but it is not the only way.

Solar power usage can be either active or passive.

1. Passive: This type of solar power usage is illustrated by leaving a car in hot sunshine for an hour or so - air conditioning off, windows and doors closed. The inside of the car will be well-heated by passive solar power - perhaps too well heated. Passive solar power can be collected in the same way by large windows, stone floors, concrete walls, and similar surfaces in a building. The power enters and heats the inside air. According to the National Renewable Energy Laboratory, passive solar power buildings use 47 percent less conventional energy than other new buildings.

Passive solar power is used every day to dry clothing hung on lines around the world. It is used in many countries to dry meat, fruits, and vegetables. Near the author’s Montana home, it is used to dry the hides of deer and elk. Passive solar power usages are ancient and many.

2. Active: Solar panels are the most common form of active solar power usage. When you can’t heat water with passive solar power, you can heat it by running it through solar panels. It’s a good way to heat water in a large swimming pool or for a short shower. Solar panels also convert solar power into usable electricity. The electricity can power light bulbs, and electrical appliances in the home. Active solar power is used in tiny photovoltaic cells that power wristwatches and calculators without need for batteries. It keeps “help” phones along highways at full power, ready for emergency use. It powers highway signs and lights in remote areas. It powers water pumps for a rancher’s cattle, far from any electric grid. It is used on boats and ships at sea. It powers recreational vehicles. It recharges cell phones and GPS units for hikers. It powers laptop computers for scientists and researchers in the field. It heats a tent for a camper, or provides hot coffee.

In remote, undeveloped areas of our world, active solar power usage cooks meals in solar ovens. It purifies water in solar water purifiers. It heats water for a shower.

Conclusion

But how much is solar power used in a day, a week, a month, and a year? That would be impossible to calculate. Suffice it to say, that it is not used as much as it could be. We could make far better use of this free energy source.

Suppose we built every new building to maximize FREE passive solar power. As referenced above, those buildings would use 47 percent less conventional energy – with no solar panels on their roofs! Add solar panels and you increase the amount of free energy.

Although no one can say how much solar power is used in any given time period, it is probably more than even the experts would estimate - and far less than it could be.

Solar power information on solar systems for solar energy houses is the topic we were discussing in the Part 2 of this article.

Solar power can be both passive and active. In our last article, we discussed passive solar power. We turn now to active solar power.

Active Solar Power

Active solar power does utilize photovoltaic (PV) panels on house roofs. It involves other solar systems, too. Active solar power can reduce the amount of electricity you need from the power grid. In some cases, active solar power will give you energy to sell back to the grid.

Here are a few ways you can install active solar power as you work to create a solar energy home.

1. Solar Water Heating: Install water heating panels on your roof, and run water through them to use solar energy for heating the home’s water. Some convert any water heater into a solar water heater.

2. Solar Swimming Pool Heating: Large solar water heating panels placed near your pool can use solar energy to heat the pool water.

3. Solar Air Heating: Install a simple, do-it-yourself solar system to heat your home’s air in winter. Air flows out into the solar heating system where it is warmed before re-entering your home.

4. Solar Electric: Solar power collected by photovoltaic (PV) panels is converted directly into usable electricity. Batteries can store this solar energy for later use. Purchase energy efficient appliances for even greater electrical savings.

5. Solar Outdoor Lighting: Use solar garden and pool lights to cut electric usage. Solar power flows through PV panels on these light fixtures, and is stored. At dusk, the lights automatically turn on. Even remote parts of your property can have light from solar energy.

6. Solar Cooking: Purchase a solar oven for cooking outdoors and saving energy. Solar energy provides all the heat you need.

7. Solar Pumping: Use solar power to pump water from a well.

For even greater efficient, combine solar power information on solar systems for solar energy houses with information on wind power. The combination of the two natural energy sources will meet most needs you have.