Complex sentence: But, when Plogoff was proposed by EDF as a site for a nuclear power plant, the local residents blocked access to the site in 1976, while renewed protests occurred in 1978 and 1979.
Split into simpler sentences: But, when Plogoff was proposed by EDF, as a site for a nuclear power plant. Local residents blocked access to the site in 1976, with renewed protests in 1978 and 1979.