ABSTRACT
In contrast, photovoltaics (PV) provides such high efficiency. An efficiency of about 10% for a surface normal to the sun (that is the one receiving the 10 000 times the present consumption) is today possible with two-axis tracking panels implying that only 1/1000 of the Earth surface can provide the present Human needs, or about 1/250 of the Emerged Lands. This is incomparably less than the space required for food and means that there is not a problem of space, despite the frequent claim to the contrary.
