The number of people in Mexico with no access to electricity has decreased in the past 10 years, mostly by grid extensions with some modest contribution from renewables, mainly PV. A highly dispersed rural population and a rough terrain make grid extensions technically difficult and economically unviable, so conventional electrification rates have decreased in recent years. On the other hand, former government programs for poverty alleviation, such as PRONASOL (1989), PRO – GRESA and OPORTUNIDADES, which were the source of funds for PV rural electrification, have been phased out or have declined to small local projects. Hence, the number of PV installations has remained practically unchanged in the last few years. Today, over 2500 rural communities have been fully supplied with SHS and other communal services through government programs, which means there are over 60 000 SHS in the whole territory. It is estimated that another 30 000 SHS have been installed outside government programs on a purely commercial basis. In addition, thousands of other PV-powered rural services have been provided, including rural telephones, schools, health centers and communal buildings. In a recent program by the Agriculture Ministry, partially financed by a GEF-World Bank grant, hundreds of small PV water pumps have been installed. The technology is becoming popular among farmers, and new programs to promote its use are in preparation. Also in preparation is another program to bring basic electricity services to 50 000 households in remote areas. In most instances PV will be the technology of choice. Total PV installed capacity in Mexico at the end of 2007 was reported at 21.7MW, of which 15.5 MW belong to rural electrification.
A distinctive characteristic of the early Mexican PV rural electrification programs was the active participation of the national electric utility (CFE) as technical normative agency, a central element for quality assurance and sustainability [29]. Under contract to CFE, the Electrical Research Institute of Mexico developed, in the early 1990s, a set of technical standards and specifications for project implementation. Laboratory testing and field evaluation protocols were also developed and implemented. Systems procurement and installation were carried out according to the prevailing law for public works.
Finance to purchase the PV systems has been mostly provided by the Federal Government, with lesser contributions from the state and municipal governments. Communities are requested to contribute to the project according to their own economic capacity. In-kind contributions, such as carrying the PV equipment to the community from the nearest point where vehicles have access, is one of the most frequent services by the community in support of the project. Funds are provided by the government as part of the patrimony for the community and, hence, no a priori money repayment mechanisms are established. However, communities are free to implement any fundraising activities that can help them maintain their systems and purchase additional equipment. A popular mechanism is the so-called communal fund, in which members of the community contribute money or man-hours or both to a common fund managed by the community representatives. The communal fund is then used to maintain the PV installations and/or to implement other projects
for the benefit of the community, such as waterworks repair, building a new schoolroom and the like. A more detailed description of the Mexican PV rural electrification program can be found in the literature mentioned in references [28, 51, 52].