Exelon said in reporting earnings that Constellation had a "record" year in 2015 driven by higher realized margins that benefited from a lower cost to serve load and strong performance in its portfolio management group.
In 2016, Exelon expects Constellation to have a more normalized cost to serve load and portfolio management performance, which the company expects will have a negative impact on earnings relative to its "extraordinary" 2015.
Constellation's load serving business experienced growth in both power and gas. In 2015, Constellation's served 195 TWh of wholesale and retail load, materially growing from 155 TWh in the prior year.
Constellation is now a top 10 marketer of natural gas and significantly increased its delivery of retail gas 40% to about 720 Bcf last year.