Many states are creating a de facto trend toward decentralization in energy policy. SPS, however, is inherently a centralized power source and will require regional coordination of powerplant regulation and transmission interties. And, while there is increasing regionalization of utility planning for generation and transmission, there is no corresponding regional coordination of regulations. Land-intensive SPS rectennas may require federally mandated, state coordinated land use and energy planning. Where federal preemption of certain state and local regulatory authority exists (as could be the case with microwave radiation regulation), state and local policies may conflict with federal policies on the SPS, with state and local regulations generally being more restrictive. Another regulatory problem not unique to SPS, but which could impact its rate of development and deployment, is the time required to gain regulatory approvals for powerplant siting and operations. The effects of the time required, now estimated to be at least a decade, could be more severe for SPS than for other technologies because of the greater number of regulatory entities likely to be involved. The establishment of a national power grid, currently under study at the federal level, may alleviate or solve some of these problems. b. Regulation of Microwave Radiation11 Currently there are no federal standards protecting the worker and/or the general public from the potential hazards of nonionizing microwave radiation exposure. The SPS power transmission system would transmit power to the rectenna via a microwave energy beam. The configuration of microwave density in the vicinity of the rectenna is shown in Exhibit 4. The U.S. "voluntary" guideline of 10/mW/cm2 is a recommended value for occupational exposure set at a value 10 times below the known threshold for biological damage and was established by the American National Standards Institute (ANSI) in 1966. It has been adopted by most of the Western World. Soviet and Eastern European microwave exposure standards are three to four orders of magnitude lower than comparable U.S. values. To a large degree, discrepancies between Eastern and Western standards are due to contrasting philosophies. For the U.S. and a majority of western countries, the concept of a risk/benefit criterion has been accepted in setting standards. This involves the use of an adequate safety margin below a known threshold of hazard.