Eskom estimates that over the next three years its debt will total R300-billion.
On Thursday, the utility announced its annual results.
Eskom made an annual net profit of R13.2-billion.
But Finance Director Paul O' Flaherty said they are still balancing a growing debt burden.
"There's debt we have on our balance sheet that matures in 2042. We had better make sure that you have your operations and your plant and you treat it with care [so] that you can actually repay that going forward."
Eskom has secured 77.6 percent of the funding needed for its construction programme.
Public Enterprises Minister Malusi Gigaba said: "We would want to see the urgent and timely completion of the current bill programme – which means that the company must continue to focus on its project management capacity."
Eskom Chief Executive Officer Brian Dames said they are already reaping the benefits.
“Our build programme has made some significant progress. We’ve added 535 megawatts of additional capacity, almost 631 kilometres of high voltage transmission lines and a significant amount of transformer capacity throughout the country.”
Meanwhile, some organisations in Cape Town said promoting energy efficiency among staff remains a priority.
Eyewitness News visited a number of buildings in the Cape Town CBD on Friday, both private and public organisations, to gauge whether they are heeding calls to conserve electricity. EWN visited the Eskom offices in Bellville as well.
On the face of it most appear to be doing their bit to save electricity.
Similar calls have become commonplace to households, especially as the winter chill sets in.
At 10PM on Friday the City of Cape Town’s office block was virtually in darkness except for one floor. The Western Cape legislature in Whale Street was also dark while most lights on the parliamentary precinct were off too.
However, it proved to be a different story at Standard Banks offices in Cape Town where all lights were on and at Eskom’s head office where most of the lights were still on.
(Edited by Tamsin Wort)