We are frequently asked how to set up experiments for use with school age level solar science faire and science experiment projects.  Often times this is asked in regards to a child wanting to make a Solar USB Charger as their experiment/ project.  

In and of itself a solar USB charger is NOT a science faire experiment or project.  It's just a device or thing you made.  Your friends may be impressed, but you'll be lacking any meaningful learning or data outside of you just making the charger, which will not impress your teacher.  The same goes for wanting to know how long it will take your phone to be charged from the sun, or comparing one solar panel to another.  Those situations just require you to do a little math, no different from asking how many liters of water are in a 10 liter bucket.  Thats not a science experiment.

In this write up we're going to show you several ways to make a very good solar experiment that can easily be used for a Science Faire or for a presentation.  Since we have experience teaching in classrooms we'll also give you some tips and suggestions that will "wow" your teacher and fellow class mates.  Seriously, we've sat through enough bad presentations and experiments to know what good ones look like.  

We're writing this as a general guide with many suggestions.  The different sections could be easily watered down for use at an Elementary Level or be made more in depth for a High School or College level.  

How to do a Good Science Faire Project

The Scientific Method

You'll want to follow the method as close as possible for this.  Question, hypothesis, material, procedure, data, conclusion.  Or close to it.  Teachers eat this up, and it's also good science.  

Or as I like to call it; Ask the right question, make a good guess, write down what tools you're using, write down how you did it, show your results, explain your results and answer your question.

The Right Question

The biggest single mistake we see kids of all ages make is not asking the right question for their project.  Frequently students will choose a project, such as making their own USB charger, that doesn't give them data or test for anything.

You must have a question that allows for data and experimentation.  These should never be simple "yes" or "no" questions.

A question such as "Will this charge my cell phone?" is a bad question.  A good question would be "Which light source produces the best solar energy?" or "What is the best position to put a solar panel to collect energy?".  These are questions that allow you to collect data and present information.

How will you do your experiment?

You need to record HOW you do you project.  While it's dull to write down minor details, this is good science.  You'll want to include a paragraph in your poster or presentation explaining this.  The goal is to outline your procedure well enough that someone else could do your project on their own.

You must have at least one variable.  (One is great for most students.)

This means you need to have something that you change to get different responses.  Lets use the previous two questions as examples.

1) Which light source produces the best solar energy?

We can then use different light sources and collect data.  Not even anything fancy, we can use a candle, a 60W light bulb, the sun, and an LED flashlight.  Great.

2) What is the best position to put a solar panel to collect energy?

Again, we can try that out any number of ways.  The most simple way would be to go outside with a solar panel and collect data.  North, South, East and West.  Do this a bunch of times over several days and you'll have tons of data.

You must also have constants

In order to compare your changing Variable, you'll need everything else to be Constant.  Lets use the above questions again.

1) Which light source produces the best solar energy?

In this situation we'd want our data collector (our solar cell) to be the same for everything.  We'd also want to also keep our distance away from our light sources to be the same.  A simple ruler can be used to measure distance.  Take a reading at 1 inch, 2 inches, 3 inches and so on.  Granted, for testing the sun we can't get any closer HOWEVER you can take your readings at noon on a sunny day and get some "best case" numbers.

2) What is the best position to put a solar panel to collect energy?

In this situation we can take insane amounts of variable data.  We'll already be taking at least 4 Directional readings (do 8 for some great data).  Our constant will be the solar panel since we won't be switching it up ever.  However, you have the option of keeping the solar panel angle as a Constant or as a Variable.  

The angle of the panel makes a big difference.  For simple experiments, keeping it at 45 degrees works best (use a protractor or just make a stand out of cardboard).  If you're wanting to make things complicated with tons of data you can also use the angle as a variable.  Now instead of taking a reading at just North, South, East, and West you'll be taking multiple readings at each direction.  North zero degrees, North 45 degrees, North 90 degrees.  

Time is also a variable and or a constant.  We recommend taking readings at noon if you're only going to be doing one reading a day.  Otherwise you'll want to take multiple readings at the same time every day.  Your 9 O'Clock reading for all four directions at 45 degrees is 4.5V.  Thats four pieces of data for 9 o'clock, then do the same at other time intervals.  

How to collect your data

Frequently students want to see how fast a battery can be charged up by a solar panel.  A battery isn't a good way to collect data since we have no way of testing how full it is.  You need to be able to get measurable numbers of some kind from your experiments.  

With solar power the most simple way of doing this is to compare Voltage.  For this you'll need a simple volt meter or multimeter.  Your teacher probably has one in their classroom, or your neighbor in his/her work bench, or you can pick one up for under $10 at a hardware store of online. They're super easy to use and will give you a number to compare back and forth, especially for a child.

We DO NOT recommend trying to record amperage, since thats a whole different ballgame and way too much work.  That is unless you're insanely motivated.

Presenting your data

When you collect your data, use a notebook.  Make your data collection look clean and smart.  Simple lines drawn across a piece of paper, all labeled, makes you look super professional.

You can also type these up easily into a word processor.  The upside being that this looks even more professional.

Charts and Graphs

The two above examples work really well for making simple line graphs.  Graphs make everything look better.  It's the same data you're already showing, but in a different way.  Teachers love this.

You can one based on Voltage vs Time of Day.

You could do one line graph with multiple lines based on "Distance from light source" vs Voltage, with each line being a different light source.  (Colors!)

You could do one line graph with multiple lines based on "Angle of the panel" vs Voltage, with each line being a different direction.  Granted, this graph would ONLY be showing data from one "Time of Day" data point.  If you took three "Time of Day" readings you could make three graphs.

Explanations

For a presentation or poster you don't want to just throw up your answer.  You need to explain things.

Assume your audience knows nothing on the topic.  Make a vocabulary list.  Explain the tools you used.  Explain how solar cells work.  Small paragraphs, with a graphic, that explain the important ideas of your project show everyone else that YOU are an expert and that YOU know what you're talking about.

One simple way to show off is to underline, bold, or italicize vocal words.  This points them out to people and also shows you know how to use them.  Plus you should be using them a lot, and you should be including a vocabulary/ important words list always.

Answer your question.  Explain how you decided on that answer.  It's ok to have a mixed answer.  

For instance, if you found that your results were the same for both 15 degrees and 45 degrees all the time, say that.  Explain that you got that data and then talk about it.  Why do you think this happened?  How could you get better or more accurate results next time?

Artifacts

One often overlooked part of a student presentation is the simple act of showing your tools or procedures.  In the above examples it would be very easy to have your solar panel, multimeter, ruler, and light sources on display.  You could even act out how you took your data.  This takes your project off the page and into real life.

Teachers love this.

Example Projects

We'll be using those two questions from before as examples, as well as very high level example project.

Project 1 - Elementary Level

Question: Which light source produces the best solar energy?

Hypothesis: Sunlight will produce the most energy.

Material: Solar cell, multimeter, sun, candle, 60W Light bulb, LED flashlight, incandescent flashlight, ruler, paper, pencil  (You can use a Solar Science Station as both your solar cell and volt meter!)

Procedure: Place the ruler next to the light source.  Measure the voltage of the solar cell using the multimeter at increments of one inch.  Measure the sun's energy at noon for five days in a row, and take the average voltage.

Data:  This is where you'd make a nice little chart with all your data.  Everything labeled, nice lines, easy to read.

This is also where you can put your charts and graphs as well.

Conclusion: The best source of energy is the sun.

I found that artificial light from any source provided very low voltage.  Even having the solar cell touching the light source provided little energy.  At every inch away from the light source the voltage dropped by X amount.

My solar data was inconsistent because we had very cloudy weather for two days.  This affected my data and made my average solar voltage lower than expected.  This also shows the problems with using natural solar energy since weather is unpredictable and high cloud coverage would cause areas to lose power.

Brown Dog Notes: This example project is super easy to do, not very time consuming, inexpensive, and every aspect of this experiment can be done by the child.

The hardest part will be presenting the data on a large poster, trifold, or powerpoint.  Charts and graphs make this a lot easier to do since they're impressive looking and take up a lot of space.

Project 2 - Middle School and High School

Question: What is the best position to put a solar panel to collect energy?

Hypothesis: I think that a panel facing East at a 50 degree angle will collect energy best.

Material:  Solar cell, multimeter, protractor, compass, watch, paper, pencil, the sun.  (The Solar Science Station is perfectly set up for this experiment.)

Procedure: Take reads at 9am, 12pm, and 3pm every day for one week.  Record the weather conditions.  Using the compass face the solar panel in each of the four cardinal directions.  In each direction take a voltage measurement with the panel at the following angles as measured by the protractor; 0 degrees, 45 degrees, 90 degrees, 135 degrees, and 180 degrees.  Record the data.

Data:  Record everything very nicely and neatly.  Even if you're going to type it all up afterwards, good note taking makes you look good.

You can also chart and graph here if you'd like.

Conclusion:

The most constantly good direction for collecting solar energy was X at a angle of X.  

You can then talk about weather conditions affecting your readings, talk about research you did on large solar installations, and even comment on solar panels you see in your community.  If you had more than one "best" direction and angle you can talk about that as well.  If you had any issues or problems, talk about it and explain how you'd change the experiment in the future.  Another good thing to talk about are "real world" situations that apply to this research.  Things such as installing solar panels on houses or large scale industrial installations.

Brown Dog Notes: The key to this project is just taking your data at the right times every day.  If you skip a day, thats fine, but you need to do a minimum of 5 days.  The more days, the more data, the more data, the better your project will turn out.

Project 3 - Very super motivated High School or College Student

Question: What improvements, if any, can be gained in power output by utilizing active solar tracking?

Hypothesis: I believe that by actively tracking the sun that a panel will increase it's daily solar output by 20%.

Materials: Solar Tracker, static solar cell (unmoving), multimeter, paper, pencil, sun (our Single Axis Tracker and Dual Axis tracker were both designed for this.)

Procedure: Take data readings from both the active and static solar cells during the day.  Lots and lots of data.  You're an overachiever, you need insane amounts of data.  Every half hour is good.

If you're feeling super overachiever, work amperage into this kind of setup.  You'll need to research how to do that first.

Data: Yup, tons of data.  Have fun charting all that.

Conclusion: What?  Did you think we'd give you the answer?  Nope nope nope.

But what you should also do is research large scale solar installations and if they use active tracking or not.  If they do, find out why or find a similar setup somewhere else in the world and compare results.  Instead of actively tracking, why not just use a preset program to move the panels?  Do you need a dual axis tracker, or will a single axis work.

Needless to say you could talk about this subject for hours on end using both your own data and research collected from real world installations.  Have fun!

The End

You can grab most of the supplies needed for these projects from BrownDogGadgets.com.  Our Solar Science Station is set up specifically for these types of projects, with it's built in volt meter and protractor.  If you're super motivated we do offer both a single axis "dumb" tracker and a dual axis "smart" tracker.  They're not very difficult to build and also feature a built in volt meter for easy readings.

Otherwise you can find a multimeter at most local hardware stores or amazon, and we have a whole bunch of solar cells to choose from.