Commenting on the event in the Welsh capital, energy minister Malcolm Wicks said it was "critical" that as many views as possible were heard on the subject and promoted a new website launched on the subject.
"We're part way through a week consultation and I want as many people as possible to feed into that via the interactive website," he explained.
"This is a big decision with consequences either way. It's critical that we listen to all the views and get it right."
The government's forum on energy comes a week after companies including EDF Energy, GE-Hitachi and Toshiba-Westinghouse submitted their applications for the construction of a new UK reactor to the Health and Safety Executive and Environment Agency.
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