National Grid:

• National energy grid is a network of interconnected parts providing electricity to all economic sectors.

• Starts at power stations and feeds into large transmission lines.

• Transmission lines are supported by pylons and have high currents.

• Electric current is sent at high voltages and low current to prevent energy waste.

• Transformers change voltages at different grid points

• Power surges or grid overloads can cause blackouts and disruptions.

Power Surge:

• A power surge is a sudden increase in an electric circuit, causing an increase in current strength.

• Causes include: lightning strikes near transmission lines, faulty wiring and energy-intensive appliances or equipment

• Short changes in voltage can cause a surge.

• National grid points can detect power surges or grid overloads, cutting off power supply to affected areas.