Geothermal Energy

Question 1

What is geothermal energy?

Answer 1

Using the natural heat found with depth, into the Earth’s Lithosphere.

Question 2

What is geothermal gradient?

What would a steep gradient mean?

Answer 2

The change in temperature with depth.

A steep geothermal gradient means there are high temperatures close to the surface.

Question 3

Name a country with a steep geothermal gradient

Answer 3

Iceland

Question 4

What is the potential of geothermal energy compared to current consumption?

Answer 4

Potential to provide 10 times GPEC

Question 5

How has geothermal energy impacted Iceland’s development?

Answer 5

• Evolved from a poor country, reliant on peat and oil imports, to a more developed, prosperous country that is virtually self-sufficient in terms of energy.

Question 6

What % of Icelandic homes have direct heat from geothermal energy?

Answer 6

89%

Question 7

What is geothermal energy used for in Iceland?

Answer 7

• Heat for homes, cooking, growing crops etc.
• Electricity
• Tourism, such as heating the lake of the Blue Lagoon

Question 8

Name the location of a geothermal project in the UK

Answer 8

Southampton

Question 9

Southampton:

• How many tonnes of oil are being saved every year?
• How is the energy being used?

Answer 9

• 1000 tonnes

- Heating and hot water

Question 10

What type of location or underlying geology is suitable for extracting geothermal energy?

Answer 10

• Volcanically active plate margins
• Granite areas with high heat flow
• Sedimentary basins with shallow rock strata

Question 11

Give 3 advantages of geothermal energy

Answer 11

• Low emissions, reduces greenhouse effect and acid rain etc.
• Reliable; not impacted by weather and can be used all year round
• Low land use

Question 12

Give 3 disadvantages of geothermal energy

Answer 12

• Few sites are suitable for the technology currently available
• High initial cost of drilling
• Heating systems can be expensive and some require large amounts of clean water and/or anti-freeze in winter (which can produce greenhouse gases)