DTE Energy misses quarterly profit estimates as energy trading unit swings to loss

April 30 (Reuters) - U.S. Midwest utility DTE Energy DTE.N missed Wall Street estimates for first-quarter profit on Thursday, as a swing to a loss in its energy trading business offset stronger earnings from its electric utility unit.

DTE said it has invested more than $1.2 billion in its utilities during the quarter, with plans to invest more than $6 billion this year to improve the safety and reliability of its electric and natural gas infrastructure.

U.S. electric utilities expect to spend $1.4 trillion on power lines and other infrastructure-related costs over the next five years, driven by rising electricity demand, an aging grid and extreme weather such as wildfires and storms, according to a report by PowerLines, a nonprofit that advocates for utility reform.

At the energy trading segment, which consists of energy marketing and trading operations, the company reported a loss of $25 million, compared to a year-ago profit of $34 million.

However, DTE's electric segment, its largest unit by net income, reported profit of $218 million during the January-March period, compared with $147 million a year ago.

Quarterly profit in its gas unit rose nearly 2% to $210 million.

The company reaffirmed its full-year operating profit outlook in the range of $7.59 to $7.73 per share.

The Detroit, Michigan-based utility posted an adjusted profit of $1.95 per share for the quarter ended March 31, compared with analysts' average estimate of $2.01 per share, according to data compiled by LSEG.

DTE Energy serves 2.3 million electric customers in Southeast Michigan and 1.4 million natural gas customers across the state.