Lesson 2: Electricity Generation Choices
15 Topics Lesson 3: Producing Electricity
4 Topics Lesson 6: Activity – Megawatt Mansion
20 Topics 
4j. Cost of Expanding the Grid
Expanding the electrical grid is expensive, reaching as high as over one million dollars for a mile of 345 Volt lines. For the average electric bill, about 7% of the cost comes from building and maintaining transmission lines.
| Transmission Line Voltage | Cost/Mile |
| 60,000 kV | $125,000 |
| 115,000 kV | $250,000 |
| 230,000 kV | $500,000 |
| 345,000 kV | $1,500,000 |