Listen to part of a lecture in an environmental science class. The professor is discussing renewable energy sources.
Professor: We often hear about solar and wind power as the future of energy, but today I want to focus on a less talked about source: geothermal energy. Unlike solar or wind, which depend on weather conditions, geothermal energy taps into heat stored beneath the Earth's surface. This heat originates from the planet's formation and radioactive decay. To harness it, we drill deep wells into geothermal reservoirs, where hot water or steam can be brought up to drive turbines and generate electricity. One major advantage is that it provides a constant, reliable power supply, operating 24/7, unlike intermittent sources. However, there are challenges. Geothermal plants are location-specific; they need to be near tectonic plate boundaries or hot spots. Also, drilling deep wells is expensive and can cause minor seismic activity. But with technological advances, enhanced geothermal systems may expand its potential globally. Overall, while not a silver bullet, geothermal energy offers a stable complement to intermittent renewables. Now, who can tell me one key difference between geothermal and solar power?
❓ Pregunta What is one key advantage of geothermal energy mentioned by the professor?
A. It is more cost-effective than other renewable sources.
B. It provides a constant and reliable power supply.
C. It can be installed in any location around the world.
D. It does not require drilling into the Earth's surface.
✅ Respuesta correcta
It provides a constant and reliable power supply.
TOEFL Listening Tips
Skim the questions first to predict the content
Watch for signal words in lectures and conversations (however, actually, in fact)
For main idea questions, focus on the beginning; for detail questions, focus on examples and data
For attitude questions, pay attention to the speaker's tone and word choice
Take notes on keywords; don't try to write down every word
