PV modules generate electricity without emitting local air pollution or acid rain precursor gases, water pollution, or noise. Since stand-alone PV systems provide electricity without power lines, their use in protected forest areas and buffer zones can be particularly valuable for ecosystem preservation. Power-line corridors can open access for the development of forested areas, change the diversity of species within ecosystems, and cause ecosystem fragmentation. Furthermore, power-line construction and maintenance activities themselves can be quite disruptive. In many developing countries, migration from rural to urban areas is creating tremendous social and ecological problems.
People move to the city for jobs and to gain access to electricity and other modern amenities.
But urban infrastructure often has not kept pace with population growth. While it is unlikely that electricity alone will stem the tide of rural to urban migration, it is possible that solar electrification in rural areas can help by improving the quality of life there. A negative environmental impact from SHS dissemination can result from the improper disposal of lead-acid batteries. While careful recycling of lead-acid batteries is the best way to prevent this, current recycling practices vary substantially by country. As SHSs become widespread, it will be important to encourage well-managed battery recycling programs.