Last week, Mr O'Shea said the way that the energy pricing mechanism worked meant that building of renewables would not "materially" reduce UK electricity prices from current levels.
He told Laura Kuenssberg on a visit to the North Sea platform that decarbonisation was important and also a "huge economic opportunity".
However he added that "the price we see today for electricity is the same as the price that we're given to new renewable developments".
"Therefore, that new renewable development will not bring down the price."
He added that he thought the government's 2030 target for clean energy was "very challenging, but I think it's right that the energy secretary has set a very stretching target".
"It's not impossible, no, but it's not easy."
The Department for Energy Security and Net Zero said: "As shown by the National Energy System Operator's independent report, our mission for clean power by 2030 is achievable and will deliver a more secure energy system, which could see a lower cost of electricity and lower bills."