Compare energy and mineral options by costs and benefits

Grade 9 Science Worksheet

Circle the best answer.

1. Read this first

   Use the table

   U.S. utility-scale electricity, 2025 (EIA)

   Source	Share of generation	Capacity factor
   Natural gas	about 41%	58.7% (combined cycle)
   Nuclear	about 18%	91.1%
   Coal	about 17%	48.8%
   Wind	about 11%	33.8%
   Solar	about 7%	24.0% (photovoltaic)
   Hydropower	about 6%	34.4%

2. 1.

   EIA: the U.S. made about 4.43 trillion kWh in 2025, and about 41% came from natural gas. About how much is that, by Bo's math?

   • About 1.8 trillion kWh
   • About 0.18 trillion kWh
   • About 2.6 trillion kWh
   • About 18 trillion kWh
3. 2.

   Using the EIA table, about how many times as much electricity did nuclear make as solar in 2025, by Esme's math?

   • About 3.8 times
   • About 0.4 times
   • About 2.6 times
   • About 11 times
4. 3.

   Using the EIA table, about what share came from natural gas and coal together, by Jun's math?

   • About 24%
   • About 41%
   • About 58%
   • About 107.5%
5. 4.

   Using the EIA table, what does nuclear's capacity factor mean, by Luz's reading?

   • Plants stood idle for about 91% of the year
   • Plants made about 91% of what nonstop full power would make
   • Plants turned about 91% of fuel energy into electricity
   • Nuclear made about 91% of U.S. electricity
6. 5.

   Why is solar's capacity factor lower than nuclear's, by Milo's reading (EIA)?

   • Solar makes the most U.S. electricity, so it wears out
   • Available sunlight changes with time of day, season and weather
   • Solar panels give off CO₂ that slows them down
   • Nuclear plants also run on sunlight

7. Table, CO₂ from generation, 2023 (EIA), with columns Source, CO₂ per kWh

   Coal, about 2.31 pounds; Natural gas, about 0.96 pounds; Petroleum, about 2.46 pounds; Nuclear, hydro, wind and solar, none while running.

8. 6.

   Using the CO₂ table, how much more CO₂ does 1,000 kWh from coal give off than 1,000 kWh from natural gas, by Noah's math?

   • About 2,310 pounds
   • About 1,350 pounds
   • About 1.35 pounds
   • About 3,270 pounds
9. 7.

   Using the CO₂ table, about how many times as much CO₂ per kWh does coal give off as natural gas, by Pia's math?

   • About 0.42 times
   • About 1.35 times
   • About 2.4 times
   • About 3.3 times
10. 8.

    Model data: a town moves 500 kWh a month from coal to wind. About how much running-plant CO₂ does that avoid each month, by Ren's math (EIA rates)?

    • About 1,155 pounds
    • About 0 pounds
    • About 216 pounds
    • About 480 pounds

11. Table, Metals and recycling (USGS 2024; EIA), with columns Measure, Figure

    Aluminum from old scrap, about 37% of U.S. use; Aluminum from all scrap, about 3.6 million tons, 44% of it old scrap; Copper from scrap, about 35% of U.S. supply; Energy for cans from recycled aluminum, about 95% less than from ore.

12. 9.

    Model data: making a batch of cans from ore takes 100 units of energy. Using EIA's 95% figure, about how much would recycled cans take, by Zee's math?

    • About 5 units
    • About 195 units
    • About 95 units
    • About 0.95 units
13. 10.

    Using the metals table, what share of U.S. copper supply came from sources other than scrap, by Ari's math?

    • About 3.5%
    • About 65%
    • About 37%
    • About 135%