The 133-year-old energy holding company had an up and down 2019. Exelon’s revenue slipped 4.3% last year, down to $34.4 billion from nearly $36 billion the year before. Net income, however, surged an impressive 46%. (For that, you can credit higher utility earnings, made possible by regulatory rate increases across the majority of Exelon’s divisions, including Baltimore Gas and Electric.) The Chicago-based energy giant remains a powerful force in generation, transmission, and distribution of electricity and natural gas.