By BOB METCALFE
After the Internet, the next big thing will be cheap and clean energy. Coal, oil and gas pollute and are increasingly expensive: We need alternatives. Because nuclear energy (stored among particles inside atoms) is millions of times more dense than chemical energy (stored among atoms in molecules), nuclear reactors belong high on our long list of energy alternatives.
Nuclear energy is released during fission and fusion. During fission, large elements like uranium are split into smaller elements. During fusion, small elements like hydrogen are combined into larger elements. These two processes have occurred naturally since the beginning of time -- 13.7 billion years. The Earth is warmed naturally by its own nuclear fission reactors within and also by the sun, that big nuclear fusion reactor.
Today, 20% of our electricity is provided by 104 nuclear energy plants in the United States. These are already cheaper and cleaner than burning coal, oil and gas with all their pollutants, especially CO2. But these plants are all run on big old nuclear reactors, which nobody but the utility companies likes very much.
The good news is that the big names in nuclear energy -- like Areva, Hitachi, General Electric and Toshiba -- have recently been joined by a bevy of high-tech start-ups seeking to develop advanced nuclear-reactor designs for both fission and fusion energy production. So far, there are five fission and two fusion start-ups, among them Hyperion, NuScale and Tri Alpha.
Balance of article: The Wall Street Journal