Session 2 Flashcards
What are 2 methods to account for primary energy
There are two ways to do accounting for primary energy.
- Direct equivalent method -> this way shows a bigger portion of fossil fuels
- Substitution method account for therma losses when using fossil fuels.
define Secondary energy
Converted energy (e.g., electricity, gasoline, kerosene)
define Final energy
Energy delivered to end users (electricity at socket, often via market transaction)
define Useful energy
Energy actually converted by devices into useful functions (e.g., heat, motion, light).
What is supply side mitigation ?
- Focuses on how energy is produced
- Includes:
○ Renewables (e.g., solar, wind)
○ Nuclear power
○ Fossil fuels with Carbon Capture and Storage (CCS)
○ Hydrogen production
What is demand side mitigation ?
- Focuses on how energy is used in end-use sectors
○ e.g., buildings, transport, industry- Strategies:
○ Energy efficiency
○ Behavioral change
- Strategies:
How does the electricity grid work in 3 steps ?
- Generators
○ Produce electricity using various technologies (fossil, nuclear, wind, solar, etc.)- Transmission Network
○ High-voltage system
○ Transports electricity over long distances - Distribution Network
○ Lower voltage
Delivers electricity to consumers (homes, businesses)
- Transmission Network
What does dispatchable generation mean ? give examples of dispatchable vs non dispatchable energy
= sources of electricity that can be programmed on demand at the request of power grid operators.
Dispatchable: gas, hydro
Non-dispatchable: Solar, wind, nuclear (variable, dependent on weather/continuous generation)
Define learning rate
The fractional reduction in cost for reach doubling of cumulative production or capacity
What is brown hydrogen?
Hydrogen produced using fossil fuels like coal, typically through gasification. It has high carbon emissions.
What is blue hydrogen?
Hydrogen produced from natural gas ,with carbon capture and storage (CCS). Lower carbon than brown, but not zero-carbon.
What is green hydrogen?
Hydrogen produced using electrolysis powered by renewable energy (e.g., wind, solar). It is the lowest carbon option.
Why should hydrogen strategies consider country-specific factors?
diff types of hydrogen might not be suitable for all countries depending on energy infrastructure, emissions goals, and resources available in a country.
what is capacity factor ?
= The ratio of actual electricity output/max capacity
Used to compare consistency in electricity generation of different techs (help spot dispatchable/non dispatchable sources)
eg. capacity factor of solar 15-25%, vs nuclear 80-90%
What is levelised cost of electricity
LCOE =Total lifetime cost ÷ Total electricity produced
To compare generating techs with different cost profiles.
Helps assess which sources are most cost-effective in the long run
What does LCOE not account for ?
LCOE doesnt account for
- non dispatchability ( System Integration Costs)
- effect of variability
in $/kWh
eg.
Backup and flexibility costs needed to manage variable renewables:
Energy storage (e.g. batteries)
Grid infrastructure (e.g. interconnection between countries)
What is emission intensity ?
= total lifecycle emissions (construction, materials, operation) per unit of electricity produced.
in gCO₂/kWh
What is land area
land (in km2) required to generate a certain amount of electricity (1 TWh/year)
in km2/Twh/yr
Important for comparing technologies — especially renewables.
