Most companies didnt bother to respond, some did but soon lost interest when they realised I had done my research and didnt want to just go with 'what everyone else does' (whatever that means). I started making enquiries to Solar installation companies in the autum of 2022. M H September 2023 I was left with a professional and tidy installation. You don't have to do this, I just like to :) As a user I get access and control over the system, enabling me to tweak and adjust as I need. Even at this time of year my bills have been halved and will only improve as I get the system setup to my liking.

As to the actual result from the installation, very pleased with the outcome so far. Based on my experience there is nothing I could find fault with the company and I plan to recommend them highly if anyone asks (my first is already talking to them). After sales service has been excellent, including a follow up visit from a technician to go through any queries I had and to verify all had been done correctly. This resulted in no surprises at installation. Checking the roof, the attic where I was siting the equipment, the main fuse board and even where the earth was situated in the hotpress. Their site visit was the most thorough of them all.

From the outset, each member of staff I dealt was fantastic. You have a fair idea of what you are getting into with them before even making contact. Their prices are very competitive and they show clear indicative examples on their site, which I think is very open. At no point did I find them trying to oversell what I didn't need. I found them not only knowledgeable but willing to discuss any concerns and ideas that I had. However your system probably is never discharged more than about 50% but factoring in that inefficiency, your net real world charging time is still right around that 70 hour mark in my estimation.Paul Doyle November 2023 Each member of staff I dealt was fantastic I did a lot of research and spoke to many Solar installers before settling on Purevolt. You advise your charger provides 23 A 48 v, so if your batteries were completely discharged (which they never should be, and not accounting for the losses due to inefficiency of the charging process which others on this site indicate are as much as 40%!) it should theoretically take about 70 hours to recharge your system. So in effect, you have created a 48 v 200 ah battery out of each group of 4, and you then tied 8 of those groups together in PARALLEL to form a system of 48 v 1600 ah. You say they are in PARALLEL in groups of 4, but you probably meant in SERIES in groups of 4 as you indicate that you have a 48 v system. I am no expert but I will take a shot at this, though your question was a year ago and I assume you got an answer by now! You have 32 12 v batteries. so your formula is way off! replacing 120Ah with a 13a charger would require at least 24 hours. If the battery had a capacity of 240Ah, and was discharged to 120Ah, (like your example) it would take about 6 hours to replace 72Ah (50-80%), and significantly longer to replace the other 48Ah (80-100%) keeping in mind 14.6v would not really get you to 100%… this would require a higher (equalizing) voltage of say 15.5v for several hours. so, the charge rate decreases and charge time increases significantly, as the battery becomes more charged. so by the time it’s at say 90% charged, it may only accept about 5 or 6 amps. but then, as the battery builds up resistance, the amps begin to taper off, and taper off more quickly as the battery becomes increasingly charged.

So, 50% of available capacity = 60Ah… at 14.6v and 13a, it would take about 3 hours to get from 50% – 80% available capacity. this alone throws your charge times way, way off. also, you are assuming the top 20% of battery capacity (80-100%) is replaced at the same rate as the first 30% (50%-80%). nor have you considered a 120Ah battery should only be discharged to 60Ah (50% of its capacity). You have not factored in the charge voltage.

24 volt solar battery