President Barack Obama's $3.55 trillion budget, which was unveiled on Thursday, maintains his strategy to reduce carbon dioxide emissions that contribute to climate change by selling off all emission permits to industries. This approach differs from some members of Congress, including some within Obama's own Democratic Party, who advocate for giving away at least 50 percent of these permits in the initial stages of the plan to help ease the transition to a less carbon-intensive economy. Critics are concerned that imposing charges on companies for their carbon emissions could further strain an already struggling economy. The plan to sell all emission permits is expected to generate $646 billion in revenue during the program's early years, and White House budget director Peter Orszag confirmed that this figure would not change when more details about the budget request are released next week. Orszag informed reporters that there would be no alterations to the climate proposal, despite not providing full details of the upcoming announcement. In the previous year's presidential campaign, Obama expressed his desire for all emissions permits to be sold rather than distributed for free, but he has indicated some flexibility on this issue. According to Obama's plan, carbon dioxide emissions from various sources would be limited, and companies exceeding the limit would need to purchase emissions credits from those emitting less. The purpose of this cap-and-trade system, as emphasized by the director of the Congressional Budget Office, is to incentivize companies to reduce emissions. David Elmendorf of the CBO explained to the Senate Finance Committee that giving away allowances is essentially equivalent to selling them and donating the proceeds from the auction. Elmendorf stated that revenue from auctioning emissions could reach around $1.2 trillion over a decade. The increase in costs for companies emitting emissions will result in higher prices for consumers. Some of the revenue from the cap-and-trade plan in Obama's budget is intended to be given back to consumers to counteract these price increases. Elmendorf explained that the price hike is necessary to encourage changes in behavior, and while it can be distributed differently, it cannot be avoided entirely. A bill for cap-and-trade, sponsored by Representative Henry Waxman, is currently being considered by Congress. Waxman is aiming for the bill to be passed by the end of May, but a senior Republican has suggested that it may be delayed in order to focus on healthcare reform. Representative Joe Barton believes that a delay could help Democrats gather more support for the climate change legislation. Some Democrats on the committee, such as Mike Doyle, anticipate that industry will initially receive most of the emission permits needed under the cap-and-trade plan for free, rather than through auctions, for the first 10 to 15 years of the program. President Obama has expressed a preference for limiting carbon emissions through legislation, but also has the option of using regulation to achieve the same goal. The U.S. Environmental Protection Agency announced last month that greenhouse gas emissions pose a threat to human health and can therefore be controlled as a pollutant.