Not very much - Earth is arround 150 000 000 km from the sun, this means that all the energy from the sun hits an area of 2.8*10^17 sq.km at earths orbit, the earths radius is arround 6360 km. The earth dish is then 1.27*10^8 sq. km, so 4.5*10^-10 or 0.000 000 045% of the suns energy reaches the earth.