Well sort of and finally all combined at the same time.
The first battery system we were involved in as a team was way back in 2012. Back then, it was either for off-grid systems or and is still often the case, a wonderful talking point.
Now this all comes down to the cost of the battery versus how much power you get back and the break-even point. In some parts of the country, for example, they pay over 1 dollar per kilowatt. This means a 10kw battery that might cost 20 grand installed will give you $9 per day. Taking into account you can't drain the battery all the way! So, therefore, it will generate $3285 (in a perfect usage scenario we must add) per year. So, it will take 6.08 years to break even and will give you just under 4 years of free power.
This is all well and wonderful, but the figures do change drastically if you only pay 38 cents per kilowatt, as many reading this will do. Then the figures are more like $1248 per year, and you won't break even during the lifetime of a battery. Meaning if you do put one on, it's for other purposes rather than saving money.
Do beware of anyone selling you batteries as a magic solution without showing you the maths and then, double-checking yourself! It's such a common scam at the moment! However, for some, batteries do make sense and are a great addition to the home. It's up to you to do your research on how that will work for you.
As usual, we hope we've been able to shed some light on a complex and confusing topic.
Stay sunny everyone.