L7 - Fossil fuels 2: Carbon capture and storage

Question 1

How much carbon can be emitted to still achieve the 2 degree target?

Answer 1

• Current estimation is about 300GtC (or less for more ambitious targets).
• That’s about 25 years with current rate. From then it has to be zero.
• Some have argued that “carbon budget” for 1.5°C is already spent.
• These numbers are ofcourse highly uncertain and widely contested.

Question 2

How much carbon can be emitted to still achieve the 2 degree target?

Answer 2

• Current estimation is about 300GtC (or less for more ambitious targets).
• That’s about 25 years with current rate. From then it has to be zero.
• Some have argued that “carbon budget” for 1.5°C is already spent.
• These numbers are ofcourse highly uncertain and widely contested.

Question 3

Which are the four components of CCS?

Answer 3

1) CO2 capture at large point source of emissions
2) CO2 transport and logistics
3) CO2 injection into a geological storage site
4) CO2 storage for an extended time period

Question 4

Which are the storage possibilities? Describe them.

Answer 4

• Current projects and this lecture focus on geological storage. This means storing CO2sort of like fossil gas has been stored in their wells for millions of years.
• Carbon could also be stored as carbonate rocks, woody biomass, biochar, organic matter in soils or sediments or dissolved in oceans.
• O2 is liquefied and injected into porous rock layers located hundreds or thousands of meters below the surface. Consumes significant compression and pump work.

Question 5

What is EOR?

Answer 5

Enhanced Oil Recovery

CO2 is injected into depleted oil wells to extend production.

Question 6

What is the goal of CO2 capture?

Answer 6

The goal is to obtain as pure CO2 as possible.

Question 7

What is air capture of CO2?

Answer 7

CO2 capture from ambient air would allow for “negative emissions”, with CO2being actively drained from the atmosphere.

Question 8

What is BECCS?

Answer 8

Bio-Energy CCS

CO2 is drained from the atmosphere when biomass grows, and provided in concentrated formas flue gas from biomass plants.

Question 9

What is the LCOE

Answer 9

Levelized Cost Of Electricity (LCOE)

The required average selling price of electricity produced to cover building and operation of a power plant over its assumed economic lifetime.