KABUL—Afghanistan’s capital could be plunged into darkness as the winter sets in because the country’s new Taliban rulers haven’t paid Central Asian electricity suppliers or resumed collecting money from consumers.

Unless addressed, the situation could cause a humanitarian disaster, warned Daud Noorzai, who resigned as chief executive of the country’s state power monopoly, Da Afghanistan Breshna Sherkat, nearly two weeks after the Taliban’s takeover on Aug. 15.

“The...

KABUL—Afghanistan’s capital could be plunged into darkness as the winter sets in because the country’s new Taliban rulers haven’t paid Central Asian electricity suppliers or resumed collecting money from consumers.

Unless addressed, the situation could cause a humanitarian disaster, warned Daud Noorzai, who resigned as chief executive of the country’s state power monopoly, Da Afghanistan Breshna Sherkat, nearly two weeks after the Taliban’s takeover on Aug. 15.

“The consequences would be countrywide, but especially in Kabul. There will be blackout and it would bring Afghanistan back to the Dark Ages when it comes to power and to telecommunications,” said Mr. Noorzai, who remains in close contact with DABS’s remaining management. “This would be a really dangerous situation.”

Electricity imports from Uzbekistan, Tajikistan and Turkmenistan account for half of Afghanistan’s power consumption nationwide, with Iran providing additional supplies to the country’s west. Domestic production, mostly at hydropower stations, has been affected by this year’s drought. Afghanistan lacks a national power grid, and Kabul depends almost completely on imported power from Central Asia.

Currently, power is abundant in the Afghan capital, a rare—if transient—improvement since the Taliban takeover. In part, that is because the Taliban no longer attack the transmission lines from Central Asia. Another reason is that, with industry at a standstill and military and government facilities largely idle, a much bigger share of the power supply ends up with residential consumers, eliminating the rolling blackouts that used to be commonplace.

That, however, is likely to come to an abrupt end if the Central Asian suppliers—particularly Tajikistan, whose relationship with the Taliban is rapidly deteriorating—decide to cut off DABS for nonpayment. Tajikistan has given shelter to leaders of the anti-Taliban resistance, such as former Vice President Amrullah Saleh, and recently deployed additional troops to its border with Afghanistan, prompting Russia to call on both nations to de-escalate.

A hydroelectric dam in southern Tajikistan in 2018. Tajikistan has been a key source of imported electricity for Afghanistan.

Photo: Agence France-Presse/Getty Images

“Our neighboring states now have the right to cut our power, under the contract,” said Safiullah Ahmadzai, the DABS chief operating officer who stayed on after the Taliban takeover and is now serving as acting CEO. “We are convincing them not to do that and that they will get paid.”

The Taliban spokesman’s office and a spokesman for the new government’s energy and water ministry didn’t respond to requests for comment.

At the time of the Taliban takeover, DABS had some $40 million in cash in its accounts, money that Mr. Noorzai said some officials of the former government tried to force him to hand over. The Taliban, starved of funds because of international sanctions, haven’t approved the use of that money to pay invoices from power suppliers. DABS liabilities have since grown to more than $90 million and are rising, Mr. Ahmadzai said. Collection from customers, meanwhile, shrunk by 74% last month, with only $8.9 million in revenue since Aug. 15, according to DABS officials.

The Taliban spokesman’s office and a spokesman for the new government’s energy and water ministry didn’t respond to requests for comment.

With government ministries not paying salaries for months and the banking system paralyzed, many Afghans don’t have the means to pay their power bills. Last year, customers in Kabul accounted for about half of DABS’s $387 million in total revenue, according to company documents.

“‘The consequences [of a blackout] would be countrywide, but especially in Kabul.’ ”

— Daud Noorzai, former CEO of Afghanistan’s state energy monopoly

Massoud, a 28-year-old who goes by only one name and sells fresh pomegranate juice from a cart on the streets of Kabul, said he hasn’t paid his DABS bill for two months. The Taliban takeover caused food prices to rise, leaving him with not enough money to settle the bill, which runs between $6 and $12 for a family of eight. “Our problems are growing every day,” he said.

“I request the international community to help us,” he said. “Our problems are growing every day.”

Farooq Faqiri, a 32-year-old market-stall holder who sells plastic jewelry in Kabul, said that his family of seven used to be able to eat meat every day but now lives on potatoes. The number of buyers of his jewelry is now a fifth of what it was. He said that they would have to skip even some of those meager meals to save enough to pay the electricity bill, which is a month in arrears. “The electricity comes from a corporation so they will not let us off the bill,” said Mr. Faqiri. “If they cut us off, we will have to go back in time and use oil for light and heat in our rooms.”

DABS needs an urgent infusion of $90 million to stave off a collapse, said Mr. Ahmadzai. He urged international donors to either settle the company’s arrears with the Central Asian nations directly or to cover the unpaid bills of Afghan consumers. “This is not a political issue, this would be a direct payment to the poor people of Afghanistan, not the government” he said. “And electricity is needed to keep the wheels of the economy turning.”

The international community pledged over $1 billion in emergency aid for Afghanistan at a conference organized by the United Nations last month. But a Western diplomat said that donors wouldn’t want to see that money—meant for saving lives in Afghanistan by providing food, shelter and healthcare—go instead to Central Asian power generators. He said that it was up to the Central Asian countries to use the money owed as leverage over the new Taliban regime.

While much of the old DABS central-management team still remain in office, the Taliban have replaced key provincial directors with clerics, though they retained company executives as deputies, said Mr. Ahmadzai. On the DABS Facebook page, Mr. Ahmadzai has praised the Taliban’s new Islamic Emirate for bringing peace to the country. Many of the professionals at DABS, just as elsewhere in Afghanistan’s corporate and government bureaucracies, have either fled abroad since the Taliban takeover or are actively trying to do so.

Mr. Noorzai said that advantageous pricing in existing power-purchase agreements with Central Asian nations is at risk unless the arrears are settled quickly. “If we do not pay them on time, then we default on our contracts and—as happens everywhere in financial markets—you compensate the risk of the client by increasing tariffs.”

Write to Yaroslav Trofimov at yaroslav.trofimov@wsj.com and Saeed Shah at saeed.shah@wsj.com