EPA Asks Electric Utilities to Reduce Leaks
The EPA has recently begun asking electric utilities to voluntarily reduce SF6 gas leaks at their facilities. SF6 is widely used as an insulator in the electric power industry, particularly in high-voltage circuit breakers and switchgear. It is an almost perfect dielectric, and although it is chemically inert, it is a potent greenhouse gas, and its release into the atmosphere is therefore undesirable.
The conventional method of locating SF6 gas leaks is the soap bubble test, which not only is time-consuming, but also requires the costly and burdensome effort of de-energizing the substation equipment. EPRI, the collaborative science and technology development organization for the power industry, has introduced the GasVue laser camera. The camera can locate SF6 leaks without the equipment being taken out of service.
The laser camera illuminates the scene with infrared (IR) energy at a wavelength that SF6 strongly absorbs. An IR detector then forms an image on a screen. The SF6 gas, which is normally invisible, is seen as black smoke against a lighter background. The GasVue laser camera was developed with EPRI support by Laser Imaging Systems of Punta Gorda, Fla.