Whow!
I take back all the little "nasties" I said about your programme. It sounds like you are almost home free from grid charges & only a year and 1/2 to break even point. Not a bad set up at all.
If you are considering a Listeroid for back up "if,as & when" the grid goes down occasionally....not a bad idea either.
Should you be looking ahead to WTSHTF and you want/need to incorporate your present set up with a potential to run your whole house for a longer time period...you have another cost expenditure to consider with the inverters, batteries, etc. or you might want to consider investing now in a larger than a 6/1 lister & gen head for future potential & peace of mind.
With your expertise in electricity you are well placed to convert the system you have one day to your own use, if need be.
Enjoyed your article, never seen a stand alone wind set that high without guide cables before.
Keep us posted on your decisions, the reasoning behind them and your progress. We all love listers. binnie (thanks for the input & the article).