@@eFIXXENERGY the layer also has a geometry tradeoff that's constrained by the anti reflective coating. Most modules now use a trapizodal bucket rather than linear surface
The UK gets between 2.2-2.9 solar hours per day on average depending on location so take your daily kWh use and divide by say 2.5 to get the kWp that would be optimal for you. Then size a battery system that will accommodate your ability to load shift your use. Standards size panels are now 400W+ each so you can very easily create arrays that will be beyond the basic DNO import limits, but the benefit would be you generate more in winter months since your array will be oversized but capped by either inverter capacity or the DNO limit.