How Does Dust Affect Solar Panel Power Output?

Abstract

Scientists can use solar power to provide electricity on the Moon or Mars, but there is one big problem—dust! How does dust cover impact the power output of a solar panel? How could scientists and astronauts mitigate this problem to keep the solar panels producing at their maximum output? Try this science project yourself and find out!

Summary

Areas of Science

Space Exploration
Energy & Power

Difficulty

Method

Scientific Method

Time Required

Short (2-5 days)

Prerequisites

None

Material Availability

Specialty materials required, see materials list

Cost

Low ($20 - $50)

Safety

No issues

Credits

Ben Finio, PhD, Science Buddies

This publication was supported by an agreement with Cornell University, under Prime Agreement MCS2107‑23‑01 from the Department of Defense, Office of Local Defense Community Cooperation. Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of Cornell University nor those of Sponsor.

Science Buddies is committed to creating content authored by scientists and educators. Learn more about our process and how we use AI.

https://www.youtube.com/watch?v=YhGD72-4q94

Objective

Measure how dust cover impacts the power output of a solar panel.

Introduction

Solar panels convert sunlight to electricity using the photovoltaic effect, where sunlight knocks electrons loose in the solar panel material, creating electrical current. Anything that covers the panels, like dust, snow, or even bird droppings, can decrease their power output. Keeping solar panels clean on Earth can be a problem, but at least humans can easily access the panels to clean them! Dust contamination on solar panels is also a problem on the Moon and Mars, with each environment posing its own unique set of challenges. 

Mars has massive dust storms that can almost completely block out the sun and leave a huge amount of dust on solar panels (Figure 1). However, the Martian atmosphere can also help clean the panels because wind can blow dust back off of them. These natural cleaning events have helped some solar-powered Mars rovers last well beyond their predicted lifespans.

Image Credit: NASA / Public Domain

Figure 1. Three different self-portraits of the Mars Exploration Rover Opportunity showing different amounts of dust on the solar panels. 

The Moon has different problems. With no atmosphere or wind, there are no dust storms, but there is also no erosion. This means that bits of moon dust are extremely sharp, like little shards of glass, since they do not get smoothed out by erosion. They can also become electrostatically charged due to solar radiation. This means that when dust does get kicked up, for example, by an astronaut's footsteps, it is extremely "sticky" and can adhere to surfaces very easily. With no wind or rain, there are no natural cleaning events to clean the panels off. 

Scientists can design dust mitigation systems to either clean solar panels off or prevent dust from sticking to them to begin with. However, these systems potentially add cost and complexity to a space mission. Understanding how dust cover impacts solar panel power output can help with a cost/benefit analysis when designing a dust mitigation system. 

In this science project, you will cover a solar panel with progressively increasing amounts of a granular material and measure the impact on its power output. Electrical power (P) is measured in watts (W). However, you cannot measure the panel's wattage directly. Instead, you will connect a load resistor with a known resistance (R) in ohms (Ω). You will then use a multimeter to measure the voltage (V) across the resistor. You can then calculate the power generated by the solar panel using this equation:

Where P is the power in watts, V is the voltage in volts, and R is the resistance in ohms. This method lets you quickly measure the power output of a solar panel under different conditions. How badly do you think dust cover will impact your solar panel's power production?

Terms and Concepts

• Solar panel
• Photovoltaic effect
• Power
• Natural cleaning event
• Electrostatically
• Mitigation
• Granular
• Watts (W)
• Load resistor
• Resistance (R)
• Ohms (Ω)
• Multimeter
• Voltage (V)

Questions

• Why is dust and dirt accumulation on solar panels a problem?
• What types of coating/contamination can happen on solar panels given the different environments on the Earth, the Moon, and Mars?
• What methods are used to clean solar panels on Earth?
• What methods could be used to clean solar panels on the Moon or Mars? Are they different from the methods used on Earth?

Materials and Equipment

• Small solar panel with wire leads
• Multimeter
• Alligator clip leads (4)
• 10 kΩ resistor (note: if you plan to do more electronics projects in the future, you can also purchase a resistor kit with multiple resistance values)
• Granular material, either:
  • Household material such as flour, sugar, sand, or dirt
  • Simulated Martian or lunar regolith
• Bowl
• Measuring spoons
• Small sifter
• Corrugated cardboard
• Pen or pencil
• Hobby or utility knife
• Sunny outdoor location to test your solar panel, or a heat lamp or a high-wattage (at least 100 W) incandescent light bulb for testing indoors

This project follows the Scientific Method. Review the steps before you begin.

1. Decide where you will do your experiment. 
   1. If you do your experiment outside, you will need to do it on a sunny day in a relatively short period of time so the sun's position in the sky does not change too much.
   2. If you do your experiment inside, you can place your solar panel directly beneath a high-wattage incandescent light bulb or heat lamp. If the room has natural light from windows, you will need to close the curtains or blinds to minimize the effect of changing sunlight on your experiment.
   3. In either location, lay your solar panel flat so the dust does not slide off. 
2. Set up your experiment as shown in Figure 2.
   1. Set up a cardboard rim to keep the dust contained on your solar panel.
      1. Trace your solar panel onto a sheet of cardboard.
      2. Use a knife to cut out a hole that the solar panel will snugly fit into.
      3. Depending on the thickness of your solar panel, cut out additional sheets of cardboard as necessary and stack them around the panel. 
   2. Connect the resistor to the solar panel.
      1. Use an alligator clip to connect one end of the resistor to one of the solar panel's wires.
      2. Use another alligator clip to connect the other end of the resistor to the solar panel's other wire.
      3. Note: in electronics, red is usually used for positive wires and black is used for negative wires, but it is OK if your alligator clips are different colors.
   3. Connect the multimeter to measure the voltage across the resistor. If you have never used a multimeter before, we highly recommend watching our multimeter tutorial video before you proceed.
      1. Plug the red multimeter probe into the port with a "V."
      2. Plug the black multimeter probe into the port labeled COM.
      3. Use an alligator clip to connect the multimeter's red probe to the positive side of the resistor (the side connected to the solar panel's red wire).
      4. Use an alligator clip to connect the multimeter's black probe to the negative side of the resistor (the side connected to the solar panel's black wire).
      5. Set the multimeter's dial to measure DC voltage in the 20V range.

Image Credit: Ben Finio / Science Buddies

Figure 2. Experimental setup.

3. Prepare a data table like Table 1. You can decide to adjust the increments and maximum amount of dust based on the size of your solar panel.

Swipe left to see more

Table 1. Example data table.

		Voltage (V)				Power (W)
Total amount of dust (tsp)	Granular material coverage (tsp/cm2)	Trial 1	Trial 2	Trial 3	Average	Trial 1	Trial 2	Trial 3	Average
0
1/2
1
...

4. Take your first voltage reading.
   1. Position your solar panel and make sure your multimeter is on. Do not add any dust to the solar panel yet.
   2. Record the voltage from your multimeter in your data table. 
   3. Reposition your solar panel slightly (just bump it a few millimeters) and take two more readings. With no dust yet, the readings for your first three trials may be identical. That is OK.
5. Apply your granular material to your solar panel.
   1. Fill a small bowl with some of your granular material.
   2. Measure 1/2 teaspoon (tsp) of your granular material into a sifter.
   3. Gently sprinkle the material onto the solar panel. Do your best to spread the material evenly over the panel, and avoid getting it on the cardboard border.
   4. It is OK if you do not get 100% of the material onto the panel. Some of it will probably stick to the sifter, so your measured amounts will not be exact.
6. Record the new voltage in your data table.
7. Tap the solar panel gently to slightly redistribute the granular material. Record the new voltage. Repeat this process for a total of at least 3 trials for this amount of granular material. 
8. Repeat steps 5–6 for each incremental amount of granular material. For example, if you added 1/2 tsp initially, then add another 1/2 tsp for 1 tsp total.
9. Continue adding granular material and recording voltages until your panel is totally covered.
10. Fill in the rest of your data table.
    1. Use a ruler to measure the length and width of your solar panel. Calculate its area in square centimeters.
    2. Use this information to fill in the column for granula material coverage in tsp/cm².
    3. Use Equation 1 from the introduction to calculate the power for each trial. Be careful with units:
       1. Make sure you had your multimeter set to measure volts (V) and not millivolts (mV). If you measured in millivolts, you will need to divide your voltages by 1,000 before using Equation 1.
       2. The resistor has a resistance of 10 kΩ, or 10,000 Ω. 
       3. As long as you use voltage in volts and resistance in ohms, then the result of Equation 1 will give you power in watts. However, it may be more convenient to report your results in milliwatts (mW). A milliwatt is 1/1000th of a watt.
    4. Calculate an average voltage and power for each amount of dust. 
11. Make a graph showing power vs. dust coverage.
12. Analyze your results.
    1. How does the solar panel's power output change with increasing dust coverage?
    2. What amount of power loss would you consider "acceptable"? Over what period of time? At what point do you think solar panels would need to be cleaned off?

Ask an Expert

Do you have specific questions about your science project? Our team of volunteer scientists can help. Our Experts won't do the work for you, but they will make suggestions, offer guidance, and help you troubleshoot.

Post a Question

Global Goals

The United Nations Sustainable Development Goals (UNSDGs) are a blueprint to achieve a better and more sustainable future for all.

This project explores topics key to Industry, Innovation and Infrastructure: Build resilient infrastructure, promote sustainable industrialization and foster innovation.

Variations

Careers

If you like this project, you might enjoy exploring these related careers:

Solar Energy Systems Engineer

Log in to add favorite More Menu

• Read More

Career Profile

Does the idea of harvesting the enormous power of the sun interest you? If you find this exciting, then you should think about installing solar photovoltaic panels on your house to collect free electricity from the sun. But how energy efficient is your home already? Can it get better? How many panels would your house need? What would the system look like? You can get the answers to these questions and more from your local solar energy systems engineer. These engineers help their residential and… Read more

Solar Photovoltaic Installer

Log in to add favorite More Menu

• Read More

Career Profile

Would you like knowing that what you do every day helps the environment and saves money? Well, that is what solar photovoltaic installers do. They outfit buildings and large solar energy farms with photovoltaic systems that convert free sunlight into clean and renewable energy. This is an exciting, emerging field that will enable you to combine a passion for the environment with mechanical and electrical skills. Read more

News Feed on This Topic

 

, ,

Explore Our Science Videos

If/else statements with micro:bit | Tutorial #3

Build A Solar Updraft Tower! | STEM Activity

Simple Soil Moisture Sensor Circuit | Science Project