Radiation from our star is unlimited (time wise, on human timescales). Our - or for that matter any living organism's - ability to capture it is limited by resource availability and the laws of physics: be it rainfall, topsoil and structural strength of wood, or be it the availability of silicon, copper, aluminum etc., and our capability to manufacture them. Not to mention adverse effects like killing ecosystems on large swaths of land by covering them with photovoltaics. One can try, but the wisdom of it is beyond me.