He also said a Bolsonaro government would push ahead with the massive Belo Monte hydro dam on the Xingú river, a tributary of the Amazon, which was criticized for displacing indigenous communities. Shelved plans for other dams in the Amazon basin could also be revived.
Ferreira said private investors would be called on to help build the infrastructure Brazil needs and that environmental factors would be fully taken into account.
Belo Monte and other hydro plans for the Amazon, the world's largest tropical rainforest, have been slammed by environmentalists for harming its biodiversity.
Bolsonaro, a 63-year-old former army captain-turned-congressman favored by financial markets, fell just short of an outright majority in Sunday's election. He will face leftist Fernando Haddad, a former Sao Paulo mayor, in a second-round ballot on Oct. 28.
Popular with Brazil's powerful evangelical and farming lobby, Bolsonaro has pledged to pull Brazil out of the Paris Agreement climate deal due to disagreements over how the Amazon should be protected.
His top agriculture adviser told Reuters on Tuesday that his government would slash fines for farmers who break environmental laws in sensitive areas like the Amazon rainforest.
Ferreira said hundreds of unfinished infrastructure projects, from railways and roads for exporting grains, will be studied and completed if viable with the help of investors through public-private partnerships.
But energy will be a priority.
"If Brazil is to return to the rates of growth that we all want, there will be a need for energy that cannot be supplied from other sources," he said in an interview late on Wednesday.
A Datafolha poll on Wednesday showed Bolsonaro strengthening his lead to 58 percent of voter support, compared with Haddad's 42 percent.
Bolsonaro, who is recovering from a near-fatal stabbing while campaigning last month, plans to rally the support of elected lawmakers on Friday near his home in the Barra de Tijuca beach district of Rio de Janeiro.
In an interview posted late on Wednesday to social media, Bolsonaro said his team had an economic agenda "practically ready" to present upon taking office in January, if he wins, including a tax reform that would not raise taxes but rather cut red tape.
Ferreira said Bolsonaro favored privatizing the transmission and distribution units of Brazil's largest utility Centrais Eletricas Brasileiras SA, known as Eletrobras, but retaining state control of power generation.
He emphasized that a Bolsonaro administration will focus on "clean" energy from hydro to wind and solar, and that environmental concerns will be given "full attention."
Ferreira struck a less moderate tone in an interview published on Thursday by newspaper O Estado de S.Paulo, where he described environmental regulators as a nuisance.
When the army was responsible for opening up roads in the Amazon during the 1964-1985 military regime, trees could be felled without permission, but today to cut down one tree "a handful of people will come and bother you," he told the paper.
Environmentalists are most concerned with Bolsonaro's plans to stop recognizing new native reservation lands and to merge the agriculture and environment ministries under the control of a farm lobby representative.