---
title: "Geothermal energy and applications"
subject: "Energy Environment and Society"
chapter: 3
key: "semester_7/energy_environment_and_society:geothermal-energy-application"
source: https://www.bctengineer.com/q/semester_7/energy_environment_and_society/geothermal-energy-application
site: BCT Engineering
---

# Geothermal energy and applications

Energy Environment and Society · Chapter 3: Renewable Energy Sources

- Asked in: 2069 Chaitra, 1+2 marks; 2069 Chaitra, 2 marks
- Video: [Geothermal energy is renewable and powerful. Why is most of it untapped?](https://www.youtube.com/watch?v=c7dy0hUZ9xI) — DW Planet A
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_7/energy_environment_and_society/geothermal-energy-application
- Whole chapter: https://www.bctengineer.com/md/semester_7/energy_environment_and_society/chapter-3

## Question

What is geothermal energy? Write down its application.

## Short answer

Geothermal energy is heat stored inside the Earth from formation and radioactive decay. Applications include electricity generation, direct use for heating (space, greenhouse, aquaculture, industrial, spas), and geothermal heat pumps for building heating and cooling.

## Answer

**Geothermal energy** is heat energy stored inside the earth. It comes from the heat left from the earth's formation and from the decay of radioactive elements in the crust. The temperature rises by about 25–30 °C per km of depth, and in volcanic or tectonic areas hot water and steam are found near the surface (hot springs, geysers). It is renewable on human timescales and available all the time (24 hours).

In Nepal there are many hot springs (for example Tatopani in Myagdi, Sindhupalchowk and Rasuwa), but the resource has been used mainly for bathing and tourism. The geothermal potential is estimated at about 30 MW (not yet exploited), and feasibility studies have been carried out at some sites.

#### Applications
**1. Electricity generation**
- Dry steam, flash steam and binary-cycle power plants. Large producers: USA, Indonesia, Philippines, Iceland.

**2. Direct use of heat**
- Space heating and district heating (Iceland)
- Greenhouse heating and agriculture; crop and fruit drying
- Fish farming (aquaculture)
- Industrial process heat, drying of timber, food processing
- Bathing, spas and tourism (balneology)

**3. Geothermal heat pumps**
- Use the almost constant ground temperature (10–15 °C) at 2–100 m depth for heating in winter and cooling in summer in buildings.

**4. Others:** snow melting, and extraction of minerals (lithium, silica) from brines.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. What is the origin of geothermal energy?
   A. Solar heating of the ground surface
   B. Heat of the earth's formation and decay of radioactive elements
   C. Friction of ocean tides
   D. Combustion in the earth's crust
   Answer: B. Geothermal heat comes from earth's formation heat and radioactive decay in the crust. (Key point: Origin)

2. Why can geothermal heat pumps heat in winter and cool in summer?
   A. Ground temperature at shallow depth is almost constant (10-15 deg C)
   B. The ground is always above 100 deg C
   C. They burn stored steam
   D. The ground temperature follows the air temperature
   Answer: A. The nearly constant ground temperature acts as a source in winter and a sink in summer. (Key point: Geothermal heat pumps)

3. Which is a direct-use application of geothermal heat?
   A. Photovoltaic power
   B. Wind pumping
   C. Biogas digestion
   D. Greenhouse heating and fish farming
   Answer: D. Direct uses include space and district heating, greenhouses, aquaculture, drying and bathing. (Key point: Direct use)

## Related in Energy Environment and Society

- [Solar thermal energy and application](https://www.bctengineer.com/question.md?key=semester_7%2Fenergy_environment_and_society%3Asolar-thermal-application) — Energy Environment and Society, chapter 3
- [Wind and geothermal advantages in Nepal](https://www.bctengineer.com/question.md?key=semester_7%2Fenergy_environment_and_society%3Awind-geothermal-advantages-nepal) — Energy Environment and Society, chapter 3
- [Types of geothermal power plant](https://www.bctengineer.com/question.md?key=semester_7%2Fenergy_environment_and_society%3Ageothermal-plant-types) — Energy Environment and Society, chapter 3
- [Wind machines, applications, limitations](https://www.bctengineer.com/question.md?key=semester_7%2Fenergy_environment_and_society%3Awind-machine-types-limitation) — Energy Environment and Society, chapter 3, asked 2×
- [Wind machine types and Nepal applications](https://www.bctengineer.com/question.md?key=semester_7%2Fenergy_environment_and_society%3Awind-machine-types-nepal-applications) — Energy Environment and Society, chapter 3, asked 2×
- [Solar intensity factors and applications](https://www.bctengineer.com/question.md?key=semester_7%2Fenergy_environment_and_society%3Asolar-intensity-factors-applications) — Energy Environment and Society, chapter 3

## Related in other subjects

- [Biomass compared with geothermal energy](https://www.bctengineer.com/question.md?key=semester_8%2Fpower_plant_design%3Abioenergy-vs-geothermal) — Power Plant Design, chapter 1
- [Geothermal energy uses and plant types in Nepal](https://www.bctengineer.com/question.md?key=semester_8%2Fpower_plant_design%3Ageothermal-use-nepal) — Power Plant Design, chapter 1
- [CMYK colour model and application](https://www.bctengineer.com/question.md?key=semester_8%2Fmultimedia_system%3Acmyk-colour-model) — Multimedia System, chapter 3
- [Application of AR system](https://www.bctengineer.com/question.md?key=semester_5%2Fcomputer_graphics%3Aar-system-application) — Computer Graphics, chapter 1