Science and engineering: How solar power works (video-based lesson)

In this 60-minute session, we’ll dive into the science behind how solar cells transform sunlight into electricity, equipping you with the technical vocabulary and grammar skills to discuss renewable energy confidently.

Through engaging activities, including listening to an expert explanation, practicing key terms like photon and P-N junction, and using the passive voice, you’ll gain a deeper understanding of this sustainable technology. By the end, you’ll be ready to explain solar power’s role in shaping a greener future.

How solar power works

Level: Upper-Intermediate (B2)
Duration: 60 minutes (save time by having students listen to the video beforehand)
Objective: By the end of the lesson, students will be able to understand a technical explanation about solar power, use related vocabulary in context, and discuss renewable energy using the passive voice.
Materials:

• Audio or written transcript of Jake O’Neal’s “How Solar Power Works” (provided below). The transcript is available on the video by expanding the video information and clicking the “transcript” button.
• Handouts with vocabulary, comprehension questions, and grammar exercises
• Whiteboard or digital platform for group activities

Lesson plan

Warm-Up (5-7 minutes)

Objective: Activate prior knowledge about renewable energy and introduce the topic.

• Activity: Write “Solar Power” on the board. Ask:
  • “What do you know about solar power?”
  • “Do you use solar energy in your country? How?”
• Task: In pairs, students discuss one renewable energy source they know (e.g., solar, wind, hydro) for 1 minute each.
• Transition: “Today, we’ll listen to an explanation about how solar power works and learn technical words to talk about it.”

Pre-Listening/Vocabulary Introduction (10 minutes)

Objective: Pre-teach 6-8 key vocabulary words/phrases from the transcript to aid comprehension.

• Activity: Provide a handout with the following words/phrases from the transcript
  1. Photon (a particle of light)
  2. Electron (a negatively charged particle in an atom)
  3. Doping (adding impurities to change a material’s structure)
  4. P-N junction (where two types of silicon meet to create an electrical reaction)
  5. Space charge region (area where electrons and holes interact)
  6. Anti-reflective coating (material to reduce light reflection)
  7. Passivation layer (coating to prevent electron recombination)
  8. Encapsulant (adhesive protecting solar cells)
• Task
  1. Match words to definitions (e.g., Photon = a) particle of light b) type of silicon c) protective layer).
  2. Teacher models pronunciation; students repeat.
  3. Quick check: “What do you think a photon does in a solar cell?” or “Why is an anti-reflective coating important?”
• Vocabulary for extension
  • Sum – The result of adding two or more numbers or quantities.
  • Total – The complete amount after adding everything together.
  • Add – To combine numbers or quantities to increase the amount.
  • Plus – A word used to indicate addition (e.g., 2 plus 2 equals 4).
  • Increase – To make something larger by adding to it.
  • Combine – To bring two or more things together to form a whole.
  • Accumulate – To gather or collect gradually by adding over time.
  • Aggregate – A total created by combining several elements.
  • Increment – A small addition or increase in quantity.
  • Supplement – To add something extra to improve or complete.

Listening/reading (15 minutes)

Objective: Develop listening or reading comprehension for main ideas and details.

• Activity 1: First listening/reading for gist (5 minutes)
  • Play the audio (or read aloud) the transcript up to 3:15 (from start to “Space Charge Region”).
  • Question: “What is the main topic of this part?” (Answer: How solar cells generate electricity using photons and electrons.)
  • Students discuss answers in pairs.
• Activity 2: Listening/reading for details (10 minutes)
  • Play/read the transcript again (up to 5:29, “Supporting Structures”). Provide a handout with 5 comprehension questions:
    1. What do photons do when they enter a solar cell?
    2. What is a P-N junction, and why is it important?
    3. What does “doping” mean in the context of solar cells?
    4. True/False: N-type silicon has an extra free electron.
    5. True/False: Electrons can move backward in the space charge region.
  • Students answer individually, then check answers in small groups.

Grammar focus: Passive voice (10 minutes)

Objective: Practice the passive voice, which is common in technical descriptions (e.g., “Photons are absorbed by electrons”).

• Activity
  • Highlight 3-4 passive voice sentences from the transcript:
    • “Photons are absorbed by available electrons.”
    • “N-type silicon is doped with phosphorus.”
    • “Anti-reflective coating is added for improved efficiency.”
  • Explain structure: Subject + be (is/are/was/were) + past participle.
  • Task: Provide a gap-fill exercise (5 sentences) where students convert active to passive voice or fill in the correct form, e.g.:
    • Active: “They add an anti-reflective coating to the cell.”
    • Passive: “An anti-reflective coating ___ (add) to the cell.”
  • Students work in pairs, then review answers as a class.

Speaking practice (15 minutes)

Objective: Use new vocabulary and grammar to discuss solar power or renewable energy.

• Activity 1: Pair discussion (7 minutes)
  • In pairs, students discuss:
    • “Why is solar power important for the future?”
    • “What challenges might solar power face?” (Prompt with ideas: cost, weather, storage.)
  • Encourage use of vocabulary (e.g., photon, efficiency, encapsulant) and passive voice (e.g., “Solar cells are made with…”).
• Activity 2: Group presentation (8 minutes)
  • In groups of 3-4, students prepare a 1-minute explanation of one part of a solar cell (e.g., P-N junction, anti-reflective coating) using 2-3 vocabulary words and at least one passive voice sentence.
  • Each group presents to the class; the teacher provides feedback on pronunciation and grammar.

Wrap-up and homework (5 minutes)

Objective: Review key points and extend learning.

• Activity
  • Ask: “What’s one new word or fact you learned about solar power today?”
  • Summarize key vocabulary and the role of the P-N junction in solar cells.
• Homework
  • Write a short paragraph (80-100 words) explaining how a solar cell works, using at least 4 vocabulary words and 2 passive voice sentences.
  • Optional: Research one other renewable energy source (e.g., wind power) and write 2-3 sentences about how it works.

For further reading:

• How Does Solar Work? – Department of Energy
• How does solar power work?