A proposed energy bill placing a cost on carbon dioxide emissions could mean huge public and private investment—and a big boost to some cutting-edge industries like biofuels, solar power, and even new developments in nuclear power.

President Obama, with the example of the Gulf of Mexico disaster fresh in the public’s mind, is renewing the push for just such legislation. He’s invited leaders of both Congressional parties to a White House energy summit Wednesday, repeating the strategy he used to pass health care reform, although this time he's hoping to get some Republican support for his plan.

If Obama and his congressional allies are successful, that could mean an extra $22.5 billion in annual spending in the energy sector alone by 2030. In all, the Peterson Institute for International Economics says more than $40 billion in government and private-sector funds would be spent on energy.

Here’s a quick look at five areas of opportunity for entrepreneurs should Congress pass energy legislation this year:

Electric vehicles: Already, there’s been plenty of movement on the electric-vehicle front this year. Nissan sold out its initial run of Leaf all-electric cars before the first one even rolls off the line. Electric-car maker Tesla plans an initial public offering and is teaming with Toyota to make electric cars in the future. And General Motors is rolling out its extended-range electric hybrid Chevrolet Volt later this year.

All of these developments already are being subsidized by tax breaks of up to $7,500 per vehicle sold. If comprehensive energy legislation passes, look for acceleration not just among the big carmakers toward electric vehicles, but in the industries that support such vehicles. Companies like Better Place, which is dedicated to building the electric equivalent of gas stations, could see their business boom, as could companies like A123 Systems Inc., which is building battery technology. Some investors, including Alan Salzman of Vantage Point Ventures, call this wave of electric vehicles the first generation and expect the technology to be both cheaper and more widely adopted within the next decade.

Wind and solar power: With pressure from the federal government coming in the form of a cost for emissions of carbon dioxide caused by burning coal, oil, and natural gas, look for a lot more action on the wind and solar front. That can include huge companies like Spain’s Iberdrola, the world’s biggest supplier of wind power, and General Electric, which makes wind turbines. But it’s also an area of opportunity for venture-funded companies like Bright Source, which is focused on building utility-scale solar electric plants, as well as for small players with innovative models for installing solar at individual homes and businesses. Another group of companies that likely would benefit are those developing so-called thin-film solar, which is less efficient but potentially cheaper than traditional photovoltaic solar panels.

Natural gas: Some form of oilman T. Boone Pickens’ vision of heavy transport trucks being driven by natural gas instead of diesel is likely to come to fruition if the nation moves away from oil. Such big rigs are too big for the current generation of electric-vehicle technology. But natural gas could be used to drive them. The good news is that the United States has plenty of natural gas locked in rock beds throughout northern Appalachia, Louisiana, and Texas. Some estimates put domestic natural-gas resources on par with Saudi Arabia’s oil riches. Natural gas is also a likely contender to take a larger share of U.S. power production if legislation capping carbon dioxide emissions is enacted, because natural gas is the cleanest burning of the fossil fuels.

Nuclear power: There’s a reason John Rowe, CEO of the giant Chicago-based utility Exelon has been an outspoken proponent of capping carbon emissions, and it isn’t entirely altruistic. His company is the nation’s largest nuclear power provider, and as such it could benefit from a system in which companies with high emissions have to buy credits from other companies with fewer emissions.

Nuclear’s biggest advantage is that it produces virtually no emissions. And Obama has already signaled that his administration is going to back new nukes. So what’s the opportunity for entrepreneurial innovation in an industry that’s been around for more than 50 years? Well, there’s the matter of nuclear waste. Anyone with an idea for recycling nuclear waste, or disposing of it in some new and environmentally friendly way, could turn that idea into a huge company. And there are those like NuScale Power that is experimenting with smaller, possibly portable nuclear reactors that could provide electricity for rural areas.

Biofuels. The government is already subsidizing the development and use of corn-based ethanol. But it’s the next generation of biofuels that should cause real excitement. Many of those companies, like Craig Venter’s Synthetic Genomics, have drawn investment from venture capitalists like the legendary Vinod Khosla and major corporations like Exxon Mobil, who are betting that the fuels they bring out of the lab will be both cleaner and more plentiful than drilling for oil.

Those are just five areas that could see huge growth from a new U.S. energy policy. But there could be others. The companies that come up with a better battery, for instance, or a more efficient system for running the electric grid, could be the Edisons and Rockefellers of the 21st century.