Justifying the cost of a solar panel
To have a 120w solar panel with a MPPT charger fitted costs in the region of about £400. Before any one says anything, we need the epanel to be fitted and the cost is £60. If we are off EHU for 30 days in total we save about £4 per night or £120 overall.
Our fridge on its own uses 420gm gas per 24hours, the cost will be about £21 gas used in the 30days. Minus this from the £120 saved and you are left with £99 saving. If you add in the cost of heating the hot water and cooking, this probbaly knocks off
at least another £14 bring the saving down to about £85.
Divide the £400 by 85 and it takes you over 4 1/2 years just to break even. If my figures are correct surely this means that fitting a solar panel is not really a viable option unless you rally a lot or spend weeks on a site with no EHU.
Granted we could opt for a lower wattage panel, but there is not a significant difference between the 100w and 120w panels. A 80w panel which we think is the absolute minimum is about £100 less.
The only real advantage I can see at the moment is that the battery is topped up during the winter and you can use CLs that are sometimes better located to an area than others with EHU and they are quieter CLs.
Can you persuade me otherwise?