Human Interaction With Rocks (geothermal)

Question 1

What is geothermal energy

Answer 1

It is energy that is extracted from the earths core

Question 2

How is geothermal energy created

Answer 2

Heat from hot igneous rocks are used to heat water and create steam for electricity

Question 3

Name two country’s that use geo thermal energy

Answer 3

New Zealand and Iceland

Question 4

Where is iceland positioned which allows it to use geothermal energy

Answer 4

Its position on the mid-Atlantic ridge allows it to use geothermal energy to heat water and make electricity

Question 5

How many geothermal power plants are in Iceland

Answer 5

5

Question 6

What percentage does geothermal energy give hot water and electricity to

Answer 6

32% electricity

Provides water for 98% of homes

Question 7

What percentage of homes use geothermal energy as a heat source

Answer 7

85%

Question 8

What is Iceland’s capital

Answer 8

Reykjavik

Question 9

What does geothermal provide for some footpaths in rejkjavik

Answer 9

It beats some footpaths

Question 10

Explain how water is heated and how we get the water

Answer 10

> magma pushes through fissures and has temps of over 1200 degrees
magma near the surface heats water above boiling point (over 200)
hot water is captured by drilling 2km down into hot rock

Question 11

What can you say about rock temp increasing

Answer 11

Temp increases naturally with depth by 25 per km

Question 12

What happens after hot water is captured

Answer 12

It is distributed to home and industrys to supply hot water and heating

Question 13

How do greenhouses benefit from geothermal energy

Answer 13

Water is used to heat the greenhouses

This allows Iceland to produce salad crop cheaply and reduce expensive imports

Question 14

How is electricity formed by geothermal energy

Answer 14

Water is pumped into wells, heated and turned into steam

It then returns to the surface where it is used to turn turbines within a generator which in turn creates electricity

Question 15

What happens when the steam cools

Answer 15

It condenses back into water

Is injected back underground and cycle is repeated

Question 16

Name two environmental advantages of geothermal energy

Answer 16

It reduces the need for fossil fuels (low CO2 emissions compared to fossil fuels)
Helps reduce harmful greenhouse gas emissions
Could help reduce dangers of climate change

Question 17

Is geothermal energy cheaper than fossil fuels

Answer 17

Yes it is 80% cheaper and is low home heating costs

Question 18

Give 2 disadvantages of geothermal energy

Answer 18

Environmental concerns - geothermal energy leads to emmisons of sulphur dioxide which polluted out water system
High installation cost - equipment and technology is specialised (eg underground pipes)

Question 19

What happens if too much water is extracted

Answer 19

May lead to the subsidence of overlying ground

Question 20

What does subsidence mean

Answer 20

Gradual caving in or sinking of overlying ground

Question 21

Talk about the blue lagoon

Answer 21

Power plant south of Reykjavik uses mineral rock water from power stations to fill up nearby lake (blue lagoon)
It is kept at a temp of 40 degrees
There is a spa complex beside it

Question 22

What is a geyser

Answer 22

It is a spouting spring that erupts boiling water and steam every 5 minutes

Question 23

Talk about geysers in Iceland

Answer 23

They are one of the most famous tourists destinations due to the geothermal activity that occurs here
Several hot bubbling mud pools and geysers attract thousands of tourists to the area each year