"It is very clear that electricity has been a constraint on growth," Gordhan told reporters ahead of his 2014 budget speech.
"The delays at Medupi are unfortunate... really they're regrettable because if we had those supplies earlier the economy might have grown a little bit better and might have created a bit more certainty in our environment.
"But... there is not much we can do about that," he added.
After several delays, it is expected that the first of six 794MW units at Medupi will start producing electricity in the second half of this year.
The Estimates of National Expenditure show that for the next three years the bulk of the energy department's budget will go to Eskom and expanding the national energy grid.
It reveals that Treasury has made an allocation of R190m to the SA Nuclear Energy Corporation to improve its facilities.
It, however, gave no indication of far greater amounts that will be needed to procure 9 600MW of nuclear power, in a surprise step announced by President Jacob Zuma a fortnight ago.
"The additional funding is to make improvements to the Safari-1 nuclear reactor, conduct research and development and upgrade and refurbish the Pelindaba facilities in 2014/15," the Estimates of National Expenditure states.
The research reactor has been in operation at Pelindaba for nearly 40 years.