BRASILIA, May 18 (Reuters) - Brazil's lower house of Congress will vote on Wednesday on a presidential decree proposing the privatization of state-run power company Eletrobras, House Speaker Arthur Lira said on Tuesday.

Lower house lawmakers began debating the measure on Tuesday afternoon.

"It is important that there is a broad debate on the topic. We have an agreement that, out of respect for the Senate, we give senators 30 days to analyze presidential decrees," Lira tweeted.

The decree's sponsor, lawmaker Elmar Nascimento, presented his proposals to the lower house on Tuesday.

One key element is that the privatization "will depend on establishing prior contracts for natural gas-powered generation with the government" later this year, something that will not affect the timetable, he said.

Nascimento told lawmakers that 99% of the text is in line with the government's position. He also said he withdrew from the text, at the government's request, a clause that would provide for energy regulator Aneel to intervene in the market.

Eletrobras Chief Executive Rodrigo Limp said last Thursday that Lira had indicated his optimism that the vote would pass.

Earlier this month, privatization secretary Diogo Mac Cord said he expected Eletrobras would be privatized by January 2022 and that congressional support for the decree being put to lawmakers is "fantastic."

The government has said it hopes the sale of Centrais Eletricas Brasileiras SA, as the company is formally known, will deliver 25 billion reais ($4.7 billion) to Treasury coffers. ($1 = 5.26 reais) (Reporting by Luciano Costa in Sao Paulo and Lisandra Paraguassu in Brasilia Writing by Jamie McGeever Editing by Matthew Lewis)