Mr Fayyad's plan would have gradually enhanced the country's power supply through the state-owned Electricite du Liban (EDL), eventually providing full-time electricity by 2025-2026.
The goal was not achieved because of limited funding from Lebanon's central bank, Mr Fayyad said on Thursday.
Despite this, a "small and relative success" has been achieved in Lebanon, Mr Fayyad said.
People in Lebanon will now go from less than an hour of power a day to four hours of power a day.
"There was an intention to increase the power supply to eight to 10 hours, but the limited funding from Lebanon's central bank kept the supplying period at four to five hours," Mr Fayyad said at a press conference with EDL director general Kamal Hayek.
The announcement came as Lebanon grapples with constant power failures, forcing those who can afford it to rely on private generators for a 24-hour supply of electricity.
The shortage of electricity is not a new problem in a sector crippled by corruption and chronic underfunding, but the past three years of economic crisis have taken a significant toll on the sector.
Mr Fayyad said: "The increase in power supply is sustainable, as it is supported by a tariff that covers its cost. The figures show that the cost of a kilowatt-hour per house is approximately 40 per cent of the cost of kilowatt-hours provided by private generators."
In November EDL drastically increased the price it charges for electricity for first time since the 1990s, which officials said was to fund the increased supply of power. On Wednesday, EDL workers negotiated a discounted rate for electricity costs after controversy in the cabinet, after their union called for a week-long strike.
An increase in power supply depends on fuel supply, which Mr Fayad asked to be guaranteed by the central bank. But rapidly depleting reserves led to a delay in opening a credit line to pay suppliers.
"It is important that there be dynamic co-operation between the Ministry of Finance and the central ank to open the credits. We hope that the central bank will open the credits as soon as possible, so as not to delay the fuel," he said.
The overhaul of the country's electricity infrastructure is considered a crucial requirement by donor nations for providing financial assistance to lift Lebanon out of its financial woes.
Lebanon is currently facing an economic crisis that has resulted in 80 per cent of the population falling into poverty and the country's currency losing 98 per cent of its value.