Complex sentence: Both these plants are of 300MW capacity and are being built at Chashma city of Punjab province called "CHASNUPP-I", began producing electricity in 2000, and'CHASNUPP-II', began its operation in fall of 2011.
Split into simpler sentences: Both these plants are of 300 MW capacity and are being built at Chashma city of Punjab province. The first of these, "CHASNUPP-I", began producing electricity in 2000, and'CHASNUPP-II', began its operation in fall of 2011.