Yes, the attractiveness of installing a photovoltaic module is strongly influenced by your latitude, because the amount of generated electricity depends on how much light the FV modules will receive from the sky.

Decades of studies have allowed the definition of detailed maps, whose visual result I find as fascinating as interesting. They report the yearly sum of electricity generated by each single KWp (KiloWatt-peak) in every area: an amount that can even double if you move from Central Europe to Southern Italy or Spain.

I’m publishing a map of the whole Europe, but many local maps are available here and some googling will definitely cover any other world area.

Solar irradiation is an essential parameter indeed: on equal terms, it could even halve the break-even period of your investment. But many other parameters are relevant, starting from compelling public incentives. This explains why Germany, even though its territory appears quite sad in the map above, has rapidly become one of the world main hosts and producers of photovoltaic systems.

Ernst & Young has developed a research named Renewable Energy Country Attractiveness Index, whose aim is to give a complete picture of the renewable energy market. Many interesting details, including the ambitious targets set by the world’s main countries, are reported in this excellent article published in 2007. More recent and really complete data can be found in the EPIA (European Photovoltaic Industry Association) latest Solar Generation Report, developed in collaboration with Greenpeace.

Are we really going to build a clean planet for our children? Recent developments, like soaring oil prices and President Obama’s ambitious plans, give us hope.