Chapter 10 Flashcards
What is the main problem with trying to rely on renewables such as wind turbines, solar PV and solar thermal
They are not reliable due the weather not constantly being the same
How will storing energy help increase the effectiveness of renewable energy
Decreases reliance on fossil fuels
Decreases use of fossil fuels which will help fight climate change
Increases nations or regions energy security
Offering the possibility of nations or regions exporting excess energy for more income
What is compressed air energy storage
A technique used to store renewable energy during off-peak times when demand for energy is low
What are the stages of compressed air energy storage
Energy is generated during a time when demand is low which can be stored and used later
This is achieved by using this energy to operate an electrical compressor which compresses air
The compressed air is transported and stored in large quantities in an underground cavern
This compressed air can then be used at times when demand is high
The compressed air is then transported to a gas turbine where natural gas is added the gas is heated so that it expands.
It is now used to turn a gas turbine which is connected to a generator which produces electricity
What is pumped hydro storage
Energy is stored during low demand time and used at high per demand times
How does pumped hydro work
Electricity is generated at low demand times and used to operate electrical pumps
These pumps transfer water from the lower reservoir to the upper reservoir. The water at the higher level has much more energy in the form of gravitational potential energy as the water is now at a greater height.
When demand is high the water is released from the upper reservoir travelling at high pressure to the lower reservoir
The moving water spins a turbine which drives generators which produce electricity
What are the best conditions for using compressed air energy storage for storing energy
Having an already existing cavern underground
The cavern being close to high voltage power transmission
Availability of natural gas supply
The caverns location need to accessible for construction
No environmental concerns that would deny planning permission
What are the best conditions for pumped hydro as a method to store energy
Availability of existing lakes and reservoirs
Suitable topography
The site needs to be close to high voltage power transmission
Location of site needs to be accessible for construction
Needs to be no environmental issues that could deny planning permission
