Maybe these codes will help you. 
For a solar plant you don't need no output good.
Obj=factory
name=Windkraftwerk
needs_ground=1
Location=Land
DistributionWeight=100
Productivity=50
Range=10
MapColor=134
pax_level=1
Dims=1,1
intro_year=1977
climates=water,temperate,tundra,rocky,arctic
Obj=factory
name=Kohlekraftwerk
Location=Land
DistributionWeight=120
Productivity=222
Range=120
Smoke=Industry_Smoke
SmokeTile=0,0
#SmokeOffset=0,-24
SmokeOffset=0, -36
SmokeSpeed=32
InputGood[0]=Kohle
InputCapacity[0]=1000
InputSupplier[0]=2
MapColor=131
pax_level=15
intro_year=1890
Dims=2,2