Western Power, owned by the WA government, runs the transmission and distribution lines of the South West Interconnected System, outside the National Electricity Market. It sells no electricity: most households buy it from Synergy. About 70% of the Perth metro network is underground.

Electricity network
- Activities
- TransmissionDistributionMetering
- Customers
- 1.22 M· connections, June 2025
- Smart meters
- 700,000+ advanced meters, June 2024
- Outage time
- 184.8 min· normalised SAIDI 2024-25
- Outages
- 1.94· normalised SAIFI per customer, 2024-25
- Network length
- 97,309 km· 31,405 km underground, June 2025
- Coverage
- South West WA
- Perth
- Mandurah
- Bunbury
- Geraldton
- Albany
- Kalgoorlie
- Kalbarri
255,064 km² from Kalbarri to Albany and east to Kalgoorlie, plus 317 stand-alone power systems in regional areas (June 2025).