Bell Ringer

Instructions: Select one of the Bell Ringers for students to reflect on and answer.

Vocabulary

Instructions: Go over important terms and their definitions before watching the Science of Geothermal video. The student vocabulary list can be found in the Student Guide and Science of Geothermal – Starter Pack.

WordDefinitionExample
plate boundarynoun phrase; the place on Earth’s surface where two tectonic plates, which are large pieces of Earth’s outer layer, meet and move“At geological plate boundaries . . . the heat of the Earth’s interior comes very near the surface . . .”
hot spotnoun phrase; an area where magma, which is melted rock from beneath Earth’s surface, rises through the crust to form volcanoes, islands, or hot springs (like Yellowstone).“At . . . geological hot spots . . . the heat of the Earth’s interior comes very near the surface . . .”
superheatverb; to heat a liquid above its boiling point without it turning into vapor“. . . the heat of the Earth’s interior comes very near the surface and it superheats the groundwater.”
groundwaternoun; water found underground in soil and rock layers“. . . the heat of the Earth’s interior comes very near the surface and it superheats the groundwater.”
radiatornoun; a device that gives off heat from hot water or steam to warm a space“We can drill wells to tap into this hot water and steam, which can then be circulated into people’s homes through simple radiators.”
turbinenoun; a machine that spins when water, air, or steam flows through it to generate electricity“[Hot water and steam] can be used to drive steam turbines similar to those in other kinds of power plants to make electricity.”
hydraulically fracturedverb phrase; when rock deep underground is cracked open by fluid pumped in under high pressure“Vertical wells are drilled and hydraulically fractured, much like an oil and gas well.”
experimentaladjective; describes a technology or process that is still being tested and studied“ . . . . but today, it’s experimental and therefore expensive for the amount of energy that it returns.”
trenchesnoun; long, narrow ditches dug into the ground for pipes, cables, or equipment“ . . . we bury a long closed loop of pipe either in trenches or vertically to as little as 200 feet . . .”
conventionaladjective; describes a method or technology that is widely used and well-established“These systems are twice as expensive to install as conventional heating and cooling . . .”
emissionsnoun; pollutants or gases released into the air, usually from vehicles or power plants“. . . but they’re cheaper to operate, longer lasting, and produce fewer emissions.”

Quiz

Instructions: Review key concepts after watching the Science of Geothermal video. The Student Guide and Science of Geothermal – Starter Pack contain the quiz and cloze notes.
Answer Key: Q1:A Q2:C Q3:D Q4:D

Reading

Instructions: Provide students with the Science of Geothermal – Reading info sheet for an in-depth exploration of the topic.

Middle School Comprehension Answer Key:

  1. Heat from the Earth.
  2. From Earth’s formation, radioactive decay, and moving rocks.
  3. They show that heat is close to the surface.
  4. By drilling wells to reach hot water or steam.
  5. Steam spins a turbine to make electricity.
  6. Hot water is piped into homes or schools.
  7. It moves heat between buildings and the ground.
  8. Iceland, the United States, or Kenya.
  9. It is low-emissions and renewable.
  10. It is expensive to build and not available everywhere.

High School Comprehension Answer Key:

  1. Heat from Earth’s interior: residual heat, radioactive decay, and tectonic friction.
  2. It is always available and does not depend on sunlight or weather.
  3. Volcanoes, hot springs, geysers, and tectonic boundaries.
  4. Wells bring hot water or steam to the surface for energy use.
  5. EGS injects water into hot rock to create steam and expand access to more regions.
  6. Dry steam, flash steam, and binary cycle; they differ in how they use heat and pressure.
  7. It emits no steam or gases because it is a closed-loop system.
  8. Hot water is piped into buildings through district heating systems.
  9. Heat pumps transfer heat between stable underground temperatures and buildings.
  10. Iceland for heating, the United States for electricity, and Kenya for national power supply.
  11. Low emissions and renewable heat source.
  12. Land subsidence, seismic activity, and possible groundwater contamination.
  13. Drilling and surveys are expensive, but operation needs no fuel.
  14. Enhanced Geothermal Systems and advanced drilling can reach deeper, hotter zones.
  15. It is reliable, low-emission, renewable, and efficient.

Computation

Instructions: Provide students with the Science of Geothermal – Computation activity for math integration and practice.
Answer Key: Q1: Energy (MWh) = Power (MW) x Time (hours)
35 MW x 24 hours = 840 MWh
Q2: Monthly Savings: 2,000 kWh – 800 kWh = 1,200 kWh
Yearly Savings: 1,200 kWh x 12 months = 14,400 kWh
Q3: Monthly Savings: $200 – $90 = $110
$110 x 12 months = $1,320
Q4: $18,000 / $1,500 per year = 12 years
Q5: Conventional System: $10,000 + ($2,000 x 10) = $30,000
Geothermal System: $20,000 + ($700 x 10) = $27,000
Answer: Geothermal is cheaper by $3,000 after 10 years.

Data Set

Instructions: Provide students with the Science of Geothermal – Data Set for data literacy and analysis practice.

Data Table: Installed Geothermal Capacity

Cumulative installed capacity of geothermal energy, measured in megawatts

CountryInstalled Geothermal Energy Capacity, 2000 (MW)Installed Geothermal Energy Capacity, 2024  (MW)Relative Change
ChileX84X
China2226+19%
Iceland172788+385%
Indonesia5252,639+403%
Italy590772+31%
Japan533489-8%
Kenya58940+1,520%
Mexico843999+18%
New Zealand4181,275+205%
Phillipines1,8471,952+6%
Russia2381+254%
Türkiye181,734+9,535%
United States2,7932,725-2%

Source: Our World In Data

Answer Key: Question 1: Answers will vary. (Example: Countries like Türkiye, Kenya, Indonesia and Iceland made geothermal energy a national priority. The evidence is in their massive energy increases: Türkiye grew by 9,535%, Kenya by 1,530%, Indonesia by 403%, and Iceland by 385%. These huge jumps showed that they invested heavily in geothermal projects in a short period of time.
Question 2: Explanations may vary. (Example: Japan shows the biggest decrease, a drop of -8%. This suggests that Japan may have shifted away from geothermal energy to other energy sources, or faced challenges like high costs, land limitations, or environmental concerns that slowed geothermal growth.)

Question 3: Answers will vary. (Example: Mexico, Italy, and China expanded their capacity slowly but steadily. Mexico grew by 18%, Italy by 31%, and China by 19%. This suggests that they see geothermal as useful but not their main energy focus. They may be balancing this growth with growth of other energy sources.
Question 4: Answers will vary. (Example: Both Indonesia and Türkiye look like future global leaders. Indonesia has the higher total capacity at 2,639 MW, showing it already plays a major role. But Türkiye’s 9,535% growth shows it is catching up fast and putting enormous focus on geothermal energy. Both countries seem to have the resources and government support to expand further.)
Question 5: Explanations may vary. (Example: The Philippines had a surprisingly small increase – only 6%. This might be because it already had such a large geothermal base in 2000, so there wasn’t much room to expand. It could also mean the country is focused on maintaining existing plants rather than building new ones, or that it turned to other energy sources to balance its energy mix.)

Geothermal Conductivity Lab

Instructions: Use the Geothermal Conductivity Lab – Student Handout and the following Teacher Guide to conduct the lab activity.

Introduction

In this lab, students investigate how different materials transfer heat by testing substances such as sand, soil, clay and gravel. By comparing results, they will see that materials vary widely in their ability to conduct heat, and that water content and density play important roles. This activity helps students connect their observations to real-world applications in geothermal energy, where engineers must understand how underground materials affect heat flow. 

Student Objectives

Students will be able to

Materials

(per group)

Procedure

  1. Preparation Before the Lab
    • Run a trial run before class to gauge heating times with your equipment. 
      Check hot plate type: If dial-based, do some trail runs to figure out the right setting on the dial to keep the temperature around 50 degrees Celsius for this experiment (window of 40 – 60 degrees). If digital, set the target surface temperature to 50 degrees Celsius. 
    • Ensure trays or beakers fit securely on the hot plate surface, and have heat-resistant gloves and tongs available (whichever is applicable). Demonstrate safety procedures before students begin the experiment.
  2. During the Lab
    • Each student group will be assigned a material to test, and then follow the instructions on the Student Handout to safely conduct the experiment. 
    • Give students specific instructions on what setting to put their hot plates on, based on the pre-lab preparation conclusions.
    • Students will not be touching the trays or hot plate surfaces once the heating begins. They will only handle the thermometers.
  3. After the Lab
    • Turn off hot plates and allow containers to cool before disposal or clean up. 
    • Provide a location on the board or poster paper where groups can report the rate of heat transfer (this calculation is part of the graphing section of the Student Handout). Students will use this whole class data to answer the analysis questions.

Assessment Rubric

CategoryExceeds ExpectationsMeets ExpectationsNeeds Improvement
Safety and ProceduresConsistently follows all safety rules and sets up/uses equipment correctly without reminders.Follows most safety rules and sets up/uses equipment mostly correctly; may need an occasional reminder.Often forgets safety rules or sets up equipment incorrectly; unsafe or unreliable procedure.
Data Collection and OrganizationThe data table is complete, accurate, and neatly organized at all time intervals.Most data has been collected correctly; the data table is mostly clear and organized.Many missing/inaccurate data points; the data table is incomplete/
disorganized.
Analysis and InterpretationClearly explains Probe A vs. Probe B trends with correct reasoning; graphs are accurate and labeled.Describes trends with some correct reasoning; graphs may have minor errors.Little or incorrect explanation of trends; incomplete or missing analysis.
Hypothesis and ConclusionHypothesis is clear and based on material properties. Conclusion strongly supported by data, with discussion of errors/improvements.Hypothesis reasonable; conclusion somewhat supported by data; limited reflection on errors.Hypothesis vague or missing; conclusion unsupported or absent.
Connections and EngagementActively participates and makes strong, thoughtful connections to real-world geothermal applications.Participates and makes basic or general real-world connections.Rarely participates; no or inaccurate real-world connections.

Answer Key

The Student Guide contains the Geothermal Conductivity Lab – Student questions.

Analysis and Conclusion Questions

  1. Answers will vary.
  2. Answers will vary. (Example: Materials with higher density and more tightly packed particles usually conduct heat better. Moisture also increases conductivity because water transfers heat more effectively than air. On the other hand, dry or porous materials conduct heat more slowly. Composition matters too. For example, minerals like quartz or granite conduct heat better than organic-rich soils.)
  3. Answers will vary. (Sample response: Our material (moist soil) showed a moderate rate of heat transfer compared to others. It heated faster than dry sand and clay, but slower than gravel.)
  4. Answers will vary. (Sample response: Yes, my hypothesis was supported. I predicted that moist soil would conduct heat better than dry soil because of the water content.)
  5. Answers will vary. (Example: Possible errors include inconsistent probe placement, small variations in layer thickness, delays in recording the time, or slight differences in packing the material. Repeating the experiment several times would reduce random errors and give a more reliable average, making our conclusions more confident.)
  6. Answers will vary. (Example: Engineers need this information to know how quickly heat can flow toward wells or pipes. If conductivity is too low, the system may overcool the reservoir or underperform. With accurate data, engineers can design systems that extract heat efficiently long-term.)
  7. Answers will vary. (Example: If the rock has low conductivity, heat will not move fast enough to replace the heat being removed. This could cause the reservoir to cool too quickly, reduce the efficiency of electricity generation, and possibly make the plant unsustainable in the long-term.)
  8. Answers will vary depending on the material tested. (Sample response: Since our material showed high thermal conductivity, engineers could design the system to extract heat at a faster rate without cooling the reservoir too quickly. For long-term efficiency, they might use the site for electricity generation, since high-conductivity rock can provide a steady, reliable flow of heat.)
  9. The granite site would be better for electricity generation, because it allows a steady, strong flow of heat to the wells. Clay, with low conductivity, would heat up slowly and not provide enough energy for efficient electricity generation.)
  10. Answers will vary. (Example: Iceland likely has underground materials with high conductivity and active volcanic systems, so heat moves quickly to the surface and provides a strong energy supply. In regions with low conductivity materials underground, the heat does not travel as efficiently, making geothermal energy less effective and only useful for smaller-scale direct heating.)

Exit Ticket

Instructions: Access the Exit Ticket and have students reflect on and answer the prompt.