Finaly i have for me the perfect, and . . i think a very nice solution.
First the plot and after that the correspondenting script.
The highlights are;
maks = STATS_max_y
min = STATS_max_x
afgenomen = gebruikt-zon
set palette defined (-(min) "#D30000", 0 "#00F000", .1 "#FFF900", (maks) "#FF0700")
plot for [i=51:1:-1] file u 1:(($10/51)*i):(($10/51)*i) w boxes lc palette notitle,\
file u 1:10 w boxes fill empty notitle,\
For all the examples that i have made look on my site: http://ccvd.eu/Energie.html