Energy giant SSE insisted it was battling "difficult" energy market conditions as it revealed a £115.4 million loss in its retail supply business just weeks after announcing a hike in household bills.
The group, which has more than nine million customers and is the UK's second largest generator of electricity, blamed the performance on rising costs of wholesale energy, environmental and social policies and distribution.
Its overall underlying group profits fell 11.7% to £354 million in the six months to September 30.
The first half loss in its retail supply arm compares with a £48.3 million operating profit a year earlier.
SSE was the first of the major suppliers to announce a tariff rise, saying last month that it would lift prices by an average of 8.2% from Friday.
More top news
Research by Swansea University showed one in 20 students had worked in the sex industry while studying for a degree.
Writing for ITV News, Dr Daniel Cooper says the world should not become complacent about Ebola and other problems affecting Sierra Leone.
Charities warn that sitting down too long can lead to health risks such as type 2 diabetes and cardiovascular disease.