Although easing the $5 billion “circular debt” is the principal problem, experts say money is only part of the solution. Deep-rooted structural issues, exacerbated by political interference and systemic graft, lie at the heart of Pakistan’s power crisis.

Electricity theft, by rich and poor, is common. Slum dwellers steal power through illegal connections; powerful politicians and government departments simply refuse to pay their bills. Electricity officials and the police, fearing retribution, dare not cut them off.

Corruption is notorious in the private power sector, where political supporters win lucrative contracts, often at inflated costs or without even producing a megawatt of power. In 2011 the auditor general noted that the government had committed to $1.7 billion in such contracts, yet added just 62 megawatts to the national power grid.

One prominent candidate in this election — Raja Pervez Ashraf, the country’s last prime minister — has been closely identified with the power crisis. After he lost his parliamentary seat in a crushing defeat, officials with the national anticorruption body stepped in, summoning Mr. Ashraf last week to answer accusations that he had taken kickbacks worth tens of millions of dollars from foreign companies on power projects.

Even those supposed to be enforcing the law are breaking it. At one police station in Sindh Province, officers erected an illegal power connection for their air-conditioners. In other areas, electricity company officials are afraid to disconnect defaulters for fear of attack.

About 20 percent of the electricity supply disappears across the country, and up to 33 percent in the worst-affected district, as a result of dilapidated transmission lines or outright theft, said Fariel Salahuddin, a power sector consultant.