Kenya Power said that a technical fault at one of its substations in the north of the capital has caused an electricity outage that was affecting Nairobi, Mount Kenya and Coast regions, Reuters reported.

This is the first major outage in 2017, disrupting industrial activities in the capital where most businesses including salons, offices, hotels and many others rely on power to run operations. The power distributor’s General Manager for Network Management, Daniel Tare, said the fault disrupted the power feed to the city, adding that technical teams were on the ground working to restore supply, according to Business Daily.

Industrial consumers in Nairobi and the neighboring town of Thika, both affected by the outage, generate 60% of Kenya Power’s revenues. Yet, frequent power blackouts have seen many businesses install standby generators that come on during supply cut-offs, raising their operating costs.

Power outages have in the past been blamed on vandalism and an old power distribution infrastructure that is currently being upgraded. Old wooden poles are being replaced with new concrete ones for high voltage lines.