Energy company Umea Energi has decided to install ultra-violet lights at about 30 bus stops for people, which will be in place for the next three weeks.

"This is so people can get a little energy kick as they are waiting," said Umea Energi marketing chief Anna Norrgard. Umea is about 600 km north of capital city Stockholm.

The company also wanted to highlight the fact that its energy comes from environmentally sound sources, she said. Any harmful rays from the light have been filtered out of it, the company said.

Much of Sweden is plunged into long, dark winters, often with lots of snow. The sun in Umea currently rises at about 8 a.m. local time (0700 GMT) and sets at 3 p.m. The daylight hours are shortest in December, when the sun comes up at about 10 a.m. and disappears again at about 2:30 pm.

Some towns north of the Arctic circle have no daylight for several weeks in the winter. (Reporting by Patrick Lannin, editing by Paul Casciato)

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