EMIR Madruga, manager of ECOSOL, considers solar energy a fundamental strategic element for sustained development.

"Every square meter of Cuban territory receives a volume of solar energy equivalent to half a kilogram of combustible oil or 5 kilowatts of electrical energy per day, an average value that is virtually invariable throughout the year and almost uniform throughout the country," he informed Granma International.

"A product of acquired experience with the demonstrative installations developed and the infrastructure created within Copextel for design, mounting and maintenance, in conjunction with the efforts of the Electronics Industry in the production of panels, the country has been able to solve numerous electrification needs for social and economic targets in areas isolated from the network.

Madruga told us of applications such as the photo-voltaic electrification program for family doctor consultancies in the mountains and isolated rural areas, with more than 400 installations up and working; mountain hospitals, boarding schools, social centers; 2,364-plus elementary schools where TV and VCR equipment was installed in an initial stage to support the audiovisual program in the framework of the Battle of Ideas and, in a second stage, solar systems in the same number of schools to guarantee the function of computers; in more than 1,860 television salons, veritable centers for the universalization of culture; in high schools and other locations with a non-reliable service; all of which confirm the positive nature of this solution.

"Other recent applications have come to occupy a dominant place within solutions at international level," he added.

"There is already a small advance with the electrification of some 200 homes in the remotest areas of the Yateras and San Antonio del Sur municipalities in Guantánamo.

The ECOSOL specialist affirmed that "applications where photovoltaic systems are the most competitive are isolated services in places where the National Electro-energetic System (SEN) do not reach. The major advantage of these systems is their autonomy and independence, as well as the reliability of their functioning.

Phot-voltaic systems connected to grids are being more and more frequently employed. Initially they were developed for large-scale photo-voltaic plants. As electronic development advanced, smaller and more manageable systems began to be designed, installed as small domestic plants, totally adapted to housing allocated with a conventional electricity supply from public networks. In that way investment and operating costs are largely reduced and supplies are increased.

"Injection into the network systems, as in Germany, Japan and other countries can be an important complement to stability of the National Electricity Service, based on the installation of a program that develops this significant application in an accelerated manner in our country. Given the ample possibilities of its use, in the medium term the connection systems to the network should become the sector of greatest demand for PHV panels.

"Hybrid systems are being used a lot in remote applications on account of their high reliability, minimum maintenance, little or zero fuel need and reduction in batteries required. One combination that is gaining ground in importance is the eolian-photo-voltaic-Diesel. 'Intelligent control systems' (that have had a tremendous evolution) have an ample field of application in hybrid systems.

"One area of extreme importance in which solar energy is being introduced is transportation, in buses using hydrogen produced by solar panels and combustible cells."

At world level the power of photo-voltaic installations connected to the grid has virtually doubled every year since 1998; for example, of the 120 MW installed in 2000, the power grew to 200 MW in 2001. This trend is being maintained and has expanded in recent years. Countries in the vanguard of this photo-voltaic application are Japan and Germany, with 90 MW of systems installed in the grid in 2001. A very strong growth has been confirmed in recent years. In New Mexico, United States, the government installed a generator and has made plans for a further five. In comparison with Japan, systems connected to the grid in Cuba have to compete with advantages. In the case of Europe, and of Germany in particular, the generation of a Cuban system will produce more energy, due to greater insulation and radiation in our latitudes.

Another example of electricity for homes occurred at the end of 2003, when Jean Paul Robles, the manager in Cuba of Total, the fourth international oil and gas group, was dining with campesino friends of his in Viñales, but night fell and as they had no electricity, they had to end the meal in candlelight.

" Total donated modules to light 43 homes there, at a cost of 43,500 euros. It also took charge of transportation costs to the Port of Havana, according to an agreement with the UN Development Fund (UNDP) - which contributed 24,769 euros.

"We can now launch the second phase of 52 houses, with a $105,000 budget , given that we have the money and the houses are built; we just have to take off. If there are no logistical problems, it should be finished by the end of this year.

In a process like the Energy Revolution that is underway in Cuba, alternative energy is important, not only in terms of the hydrocarbon savings that it represents at a time of rising oil prices makes solar energy less economically unfavorable than that produced before, when oil prices were more competitive. To learn of international opinions on this issue Granma International continued talking to the Total representative.

"Solar energy can be taken advantage of in various ways," Robles affirmed, "either as energy in places where there is no electricity supply or as a backup for a country's distribution network. In other words, you can take advantage of solar energy to boost the normal electricity distribution network; for example, as an aid, a reinforcement in hours of high consumption: the peak hours.

"It is also applicable for savings in places where the classical system is very difficult, where the cost per kilowatt is very high. The need is calculated by specialists and is implemented, as has been the French experience in Martinique, where solar energy is cheaper than energy produced in the normal way."

In relation to situations of disaster Robles believes that solar power is interesting tin terms of backing up or producing energy in the case of hurricanes or lengthy power cuts. It can be accumulated or, as it is easily mounted and dismantled, can be produced before or after an atmospheric phenomenon without major problems or danger.

"For example, the illumination of any building, such as a hospital, can be fed with solar energy; likewise it can fuel emergency apparatuses and equipment; again, like those used in hospitals.

"Without any doubt the entire system of a hospital or another building could be made operable. You would have to do the calculations, multiply the number of panels in line with the consumption needs of the building in question and the complete power required."

In relation to costs the Total representative noted that in comparison with an oil-fired plant the initial investment might be larger, but there is no need for fuel; it is more certain and cleaner. In the case of Viñales he estimated that taking into account illumination and access to the modern means of communication like television and radio-tape recorder included in the module, the cost was $1,925 per home.

A photo-voltaic system connected to the grid basically consists of a photo-voltaic generator linked to an investor that operates in parallel with the conventional electricity grid. The concept of injection has a wide margin of applications, from small systems with low peak megawatts (LKW) of installed power to stations of various peak megawatts (PMW). The photo-voltaic generator captures solar radiation and transforms it into electrical energy which, instead of being stored in batteries, as in isolated and hybrid systems, can be directly utilized for consumption or handed over to the electrical distribution grid. These two functions are realized by a direct or alternate current converter especially designed for this application. The photo-voltaic generator or field of panels can be incorporated into the roofs or facades of homes or buildings, or via special structures.

Among the principal advantages of these systems are the following: transmission losses are eliminated (by 8-12%) and in distribution (16-22%) of electrical energy. They can also be easily installed on any building or park area well exposed to the sun and without obstacles or neighboring buildings that project shade without consuming more space than that already occupied by a building in an urban environment. They do not produce contamination or harmful side effects. They are unit systems: they allow investment in a progressive form. Operational and maintenance costs are incomparably lower than those of thermoelectric plants. Most photo-voltaic panels produced today are connected to the network from sun roofs and facades with just a few KWP to electricity centers with dozens of MWP. Thanks to their flexibility, they suppose huge savings for the energy industry.