But recently, in a historic shift, more than a dozen companies around the United States have suddenly become eager to build new nuclear reactors. growing electric demand, higher prices for coal and gas, a generous Congress and a public support fo radical cuts in carbon dioxide emissions have all com bined to change the prospects for reactors, and many companies were ready to try again. The old problems remain, however, like public fear of catastrophe, lack of a permanent waste solution and high construction costs And some new problems have emerged: the credit crisis and the decline worldwide of factories that can make components. The competition in the electric market has also changed Nonetheless, industry executives and taxpayers are spending hundreds of millions of dollars to plan a new chapter for nuclear power in the United States and set the stage for worldwide revival How it works Nuclear power is essentially a very complicated way to boil water Nuclear fuel consists of an element- generally uranium-in which an atom has an usually large nucleus. The nucleus is made up of particles called protons and neutrons. The power produces by a nuclear plant unleashed when the nucleus of one of these atoms is hit by a neutron traveling at the right speed The most common reaction is that the nucleus splits- an event known as nuclear fission-and sets loose more neutrons. Those neutrons hit other nuclei and split them, too At equilibrium-each nuclear fission producing one additional nuclear fission- the reactor undergoes a chain reaction that can last for months oreven veaBut recently, in a historic shift, more than a dozen companies around the United States have suddenly become eager to build new nuclear reactors. Growing electric demand, higher prices for coal and gas, a generous Congress and a public support for radical cuts in carbon dioxide emissions have all combined to change the prospects for reactors, and many companies were ready to try again. The old problems remain, however, like public fear of catastrophe, lack of a permanent waste solution and high construction costs. And some new problems have emerged: the credit crisis and the decline worldwide of factories that can make components. The competition in the electric market has also changed. Nonetheless, industry executives and taxpayers are spending hundreds of millions of dollars to plan a new chapter for nuclear power in the United States and set the stage for worldwide revival. How It Works Nuclear power is essentially a very complicated way to boil water. Nuclear fuel consists of an element – generally uranium – in which an atom has an usually large nucleus. The nucleus is made up of particles called protons and neutrons. The power produces by a nuclear plant unleashed when the nucleus of one of these atoms is hit by a neutron traveling at the right speed. The most common reaction is that the nucleus splits – an event known as nuclear fission — and sets loose more neutrons. Those neutrons hit other nuclei and split them, too. At equilibrium – each nuclear fission producing one additional nuclear fission – the reactor undergoes a chain reaction that can last for months or even years