At 1:31 p.m. on June 4, 1962, a switch is turned on and power from the 20-megawatt reactor near Rolphton, Ont. flows into the local power grid to "help slake the power thirst of Southern Ontario." It's a big moment for science, but nuclear power is still years away from being able to compete with coal and hydro.

• "Nuclear Power Demonstration" or NPD is the unimaginative name of the first reactor to power Canadian homes. NPD was the first Candu reactor, with a completely replaceable core that could be refuelled while operating at full power.
• NPD was located on the Ottawa River about 200 kilometres northwest of Ottawa, along the Ontario-Quebec border. It was a 20-megawatt reactor — enough to power about 10,000 homes. It operated for 25 years; long after more powerful Candu models came online.

Medium: Radio
Program: CBC News Roundup
Broadcast Date: June 4, 1962
Host: Frank Stalley, Reporter: Tom Earle
Duration: 2:01