02. Electricity, Circuits & Powering Robots

Electricity doesn’t just appear out of nowhere — it has to be generated from different sources. These sources give us the electrical energy needed to power everything from homes and schools to mobile phones and robots.

Let’s explore the main types of energy sources used to produce electricity.

⚡ Main Sources of Electrical Energy

1. Batteries (Chemical Energy)

• Most robots and small electronic devices use batteries.

• Batteries store chemical energy and convert it into electrical energy.

• Common battery types: AA cells, 9V batteries, Li-ion rechargeable batteries.

🧠 Did you know? The small round battery in your wristwatch is called a button cell.

2. Solar Power (Light Energy)

• Solar panels convert sunlight into electricity using photovoltaic cells.

• This is a clean and renewable source of energy.

• Many modern robots use small solar panels to stay charged during outdoor tasks.

🌞 Fun fact: Some school calculators and garden lamps work without batteries — just sunlight!

3. Wall Sockets (Power Grid / Electrical Outlet)

• In homes and schools, electricity comes from a power plant through wires.

• This is how large appliances and chargers get power — by plugging into the electrical grid.

4. Wind and Water (Mechanical Energy)

• In some parts of the world, electricity is generated by wind turbines or hydroelectric dams.

• These use moving wind or water to spin turbines, which generate electricity.

🌬️ In windy areas, entire villages can be powered by wind energy alone!

5. Fuel-Based Generators

• Generators use diesel or petrol to run a motor, which then produces electricity.

• These are often used when there’s a power cut or in remote places with no grid connection.

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