Electricity & Energy Grids

What is Electricity?

Flow of charged particles (electrons) through a conductor.

What are the characteristics of Electricity?

Clean at point of use, versatile energy source, but not a primary energy source.

Current (I)

Flow rate of electric charge.

Voltage (V)

'Push' driving current (potential difference).

Resistance (R)

Opposition to current flow.

Ohm’s Law

V = I × R.

How do Generators Work?

Using electromagnetic induction, moving a conductor through a magnetic field induces electric current.

What are the components of the Electric Grid?

Generation, transmission, distribution, and storage.

Eastern Interconnection

Covers states east of the Rockies.

Western Interconnection

Covers the Rockies westward.

Texas Interconnection (ERCOT)

Isolated grid that avoids federal regulation.

Layered Cake Model Purpose

To match supply to demand in real-time without large-scale storage.

Baseload

Steady, always-on sources of energy like nuclear or coal.

Intermediate Load

Adjustable energy sources such as natural gas or hydro.

Peak Load

Fast-response energy sources like gas turbines or batteries.

Advantages of Electricity: Clean at Point of Use

No direct emissions, ideal for indoor use.

Advantages of Electricity: Highly Versatile

Powers a wide range of devices and systems.

Advantages of Electricity: Efficient Energy Conversion

Electric motors have >90% efficiency compared to ~30% for combustion engines.

Advantages of Electricity: Precise Control

Allows instant on/off operation with adjustable voltage and current.

Disadvantages of Electricity: Not a Primary Energy Source

Must be generated from other resources and can cause pollution.

Disadvantages of Electricity: Storage Challenges

Batteries are expensive and limited in capacity.

Disadvantages of Electricity: Transmission Losses

Resistance in wires can lose ~5–8% of energy.

Disadvantages of Electricity: Dependence on Grid Reliability

Blackouts can disrupt homes, hospitals, and industries.

Disadvantages of Electricity: High Initial Costs

Building power plants and grid infrastructure requires massive investments.