SERRE, Italy -- In the foothills south of Naples, the world's biggest solar power station stands testimony to the quest for a source of plentiful, cheap, clean energy.


Packed into metal racks several hundred meters long, some 45,000 solar cells soak up the energy of the sun, giving off a blue-violet sheen as they turn its rays into electricity.


But touch the leads that protrude from either end of the solar panels and you will receive a lethal jolt of over 300 volts.


When the sun is out, the station pumps up to two megawatts of energy into the national power grid. Its output will eventually rise to 3.3 megawatts.


That is enough to power some 2,000 households.


"This is the largest solar power plant in operation today," Roberto Vigotti, a senior solar power engineer with state energy group ENEL, said.


He was speaking at the plant, located near the small village of Serre a short distance from the ancient Greek temples at Paestum, south of Naples.


Solar power is not yet economically viable, but scientists hope that by the start of next century enough progress will have been made to make it feasible.


In the next 10 to 15 years, Vigotti believes up to one percent of Italy's electricity consumption could come from the sun.


"Given the amount of energy that is used in Italy, that is quite an ambitious target," he said.


Having turned its back on nuclear energy in 1987 and with hardly any oil reserves of its own, Italy has tried to boost the use of renewable energy sources.


Most of its northern mountains produce hydroelectric power, and a large part of ENEL's annual $266 million research budget is dedicated to developing alternative forms of energy like wind, wave and solar power.


The returns from solar power seem meager at present but the sun's potential as a source of energy is huge. Its rays cost nothing and turning its energy into electricity does not give off any pollution.


To generate an equivalent amount of energy, a normal coal-fired power station would produce some 90,000 tons of carbon dioxide -- the gas held responsible for the warming of the earth's atmosphere through the "greenhouse effect."


Unlike nuclear power, whose spent fuel is highly radioactive and takes tens of thousands of years before it is no longer toxic, solar energy produces no nasty leftovers.


Solar power technology was first discovered in the 1950s when scientists were looking for ways to power satellites that were orbiting around the earth.


Although much progress has been made since the Soviet Union launched the first Sputnik satellite in 1957, there is still plenty of scope to improve solar power technology.


At present, only 11 percent of the energy that reaches the solar panels at Serre is actually converted into electricity.


The rest is reflected off the solar panels or lost as heat.


A further 10 percent of the electricity that is produced is lost when it is converted from direct to alternating current -- the type of electricity that all national power grids supply.


Solar power's drawbacks -- the fact that it is slave to the weather, the seasons and is useless at night -- mean that the nearby port city of Naples may never be entirely reliant on it as a source of power.


But Vigotti said it could still play a very valuable role.


"The next step is not to make more power stations, but to find ways in which power can be generated very close to where it is being used," he said.


Offices and shops, which use most of their power during the day, could be decked out with solar cells to help supplement their consumption.


Any surplus could be fed into the national grid. "The hitch is finding a safe and secure way of doing it," Vigotti said.


"But eventually, we will try to put them on the rooftops, the skylights and the terraces."