What is the cost of a photovoltaic system ?

With the selection of various options, this can not be said in general terms. Sure, everyone wants, as in the supermarket, to know the price of a product easily, offers on the Internet are available in abundance ... but : The "plant design" is to be determined individually, for each household. Off the shelf" is quickly uneconomical and thus not conducive to ecology. Island/OFF-grid plants above a certain size are usually always uneconomical. Grid/ON-Grid systems with batteries are often at the limit of economic efficiency, only systems without batteries have a great potential to be economical and to have an ecological effect.