Lawrence Livermore National Laboratory
Inertial Fusion Energy
This miniature "star" was created in the target chamber of the Nova laser, NIF's predecessor, as 300 trillion watts of power hit a 0.5-millimeter-diameter target capsule containing deuterium-tritium fuel.
NIF's 192 intense laser beams will replicate the extreme conditions needed to achieve not only fusion ignition and burn, but also energy gain – two key milestones in the scientific pursuit of fusion energy as a source of electricity. If successful, NIF will be the first facility to demonstrate both phenomena in a laboratory setting. Determining the minimum input energy needed to start the fusion process is critical to determining the viability of inertial fusion energy. Thus NIF can provide the basis for evaluating future decisions about inertial fusion energy development facilities and programs.
Fusion, nuclear fission and solar energy (including biofuels) are the only energy sources capable of satisfying the Earth's need for power for the next century and beyond without the negative environmental impacts of fossil fuels. The simplest fusion fuels, the heavy isotopes of hydrogen (deuterium and tritium), are derived from water and the metal lithium, a relatively abundant resource. The fuels are virtually inexhaustible – one in every 6,500 atoms on Earth is a deuterium atom – and they are available worldwide. One gallon of seawater would provide the equivalent energy of 300 gallons of gasoline; fuel from 50 cups of water contains the energy equivalent of two tons of coal. A fusion power plant would produce no climate-changing gases, as well as considerably lower amounts and less environmentally harmful radioactive byproducts than current nuclear power plants. And there would be no danger of a runaway reaction or core meltdown in a fusion power plant.
NIF is designed to produce fusion burn and energy gain using a technique known as inertial confinement fusion (see How to Make a Star). NIF's intense laser beams, focused into a tiny gold cylinder called a hohlraum, will generate a "bath" of soft X-rays that will compress a tiny hollow shell filled with deuterium and tritium to 100 times the density of lead. In the resulting conditions – a temperature of more than 100 million degrees Celsius and pressures 100 billion times the Earth's atmosphere – the fuel core will ignite and thermonuclear burn will quickly spread through the compressed fuel, releasing ten to 100 times more energy than the amount deposited by the laser beams. In a fusion power plant, the heat from the fusion reaction is used to drive a steam-turbine generator to produce electricity.
NIF will not be used to generate electricity, for reasons discussed in How IFE Works. But NIF experiments should bring fusion energy a major step closer to being a viable source of virtually limitless energy by demonstrating fusion ignition and burn and energy gain in the laboratory. And the timing is fortunate: Energy experts estimate that over the next 75 years, the demand for energy could grow to as much as three times what it is today, while supplies of petroleum and natural gas will decline steadily and may well be exhausted by the turn of the century. View Video
