Nuclear fusion is a potential source of clean energy Magnetic field and laser are used to the fusion reaction Cost to build the power station is very high A tokamak is nuclei in an effort to u them to trw VACUUM FELD COIL PLASMA Fig 19.16 a fusion reactor called the Large Helical Device is being built and tested by researchers in Japan. These coils create a magnetic field that contain the hot ionized gas within which nuclear fusion takes placeNuclear fusion is a potential source of clean energy Magnetic field and laser are used to the fusion reaction. Cost to build the power station is very high. Fig 19.16 a fusion reactor called the Large Helical Device is being built and tested by researchers in Japan. These coils create a magnetic field that contain the hot ionized gas within which nuclear fusion takes place