The dense smog that has enveloped Delhi is capable of causing not only health problems but also power cuts. Suspended dust particles in the air sit on power lines and combine with fog-induced moisture, leading to short circuits and tripping of electric lines. Power transmission utility Delhi Transco was to replace 11,000-odd porcelain insulators of widely used 220kV lines with silicon polymer insulators that do not trip in such foggy conditions.

But, according to sources, there has been a delay in procuring the insulators and the power department will not be able to replace them this year.

“We had planned to purchase the insulators from the Power Grid Corporation of India. But their rates were higher,” an official said, adding: “We then decided to invite tenders. The process has just begun so we will not be able to replace them.” Transco has, however, replaced porcelain insulators on 400 kV lines.