Authorities in Japan are urging people across wide areas to immediately reduce their electricity consumption.

They're warning of possible power outages Tuesday in the northeastern and Tokyo regions following a powerful earthquake last week.

The disaster is still affecting a number of power plants. The warning applies to areas served by the Tokyo and Tohoku electric power companies.

The problem is compounded by a cold snap. Temperatures are dipping, and people tend to need more power. The government wants people to conserve energy in the capital and 15 other prefectures.

TEPCO says usage in the utility's service area stood at 90 percent in the hour from 7 PM. Tohoku Electric Power Company says its rate was 98 percent.

Industry Minister Hagiuda Koichi said, "Unfortunately, if this situation does not change, widespread scheduled blackouts will be necessary to avoid accidental blackouts, like on the day of the quake."

It's especially concerning for people like Tokyo resident and ALS patient Hariu Atsushi. His ventilator only works for 12 hours on a spare battery, and a prolonged outage could put his life in danger.

His wife, Wakako, said, "I'm really worried about the possibility of the batteries running out amid a blackout."

The couple are praying any outage lasts for a short time only.