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dawkinsp

Usage of around 6 - 7.2KWh Pd
BYD 2x 2.4 (4.8) 4KWh usable @ 20%
2.7Kh @ 9x 300W LG

Given some sort of winter / Directed charging (possible using remote mode) the profile should be optimal. Summer time feed in at max should be 100% of usage.
Hydrogen Fuel Cell + hydrogen storage would also allow 100% ‘off grid’ or balance.
Estimate that with new full spectrum that 2.7kh would be 9kwh and would accommodate an full electric vehicle for local commute etc.

http://www.solax-portal.com/dz/home/overview/103525
dwilliams
Hi, I am pleased to see another SolaX installation with a link to your dashboard. It will be very useful to have another site to compare performance/behaviour. I am sure I will have a few questions if that's OK? David
dawkinsp
Sure David.
dwilliams
Thank you. I would just like to be sure I understand your installation and usage correctly from your post so that any comparison is valid. You use 6 - 7.2 KWh a day. You have 2 x 2.4KWh batteries (Lithium?) Does the 2.7Kh @ 9 x 300W LG refer to your panels? Looking at your roof on Google Earth I can only see 8 panels. Your roof orientation is almost perfect for PV being a few degrees south east with no obvious shading. Is the installation of the SolaX battery storage system a retrofit for an existing PV FIT installation & did your battery storage start 11/05/2017? I have read the second part of your post above which mentions winter / direct charging, hydrogen fuel cell etc. but I am not sure I understand it yet.
dawkinsp
This is a new install and will not show on google yet. (You are looking at the neighbours)

The batteries are 2x BYD B-Plus 2.5 kwh Lithium Ion Battery.
2.7Kw composed of 9 panels LG300S1C-A5

http://www.lg.com/us/business/solar-panel/all-products/lg-LG300S1C-A5

The batteries are now active (27th June) so you will get a good idea going forward how it plays out.


The second bit is a bit of wishful thinking based on some research. The ‘full’ spectrum panels that will pop up in a few years will see 3x the performance of those currently available. With that and some form of long term storage based on efficient hydrogen production and a 4Kw fuel cell etc.
TerFar
I've been keeping a close eye on the developments and cost of battery storage and it looks like it is now beneficial. My only disatisfaction with the SolaX is that we cannot charge the batteries from off-peak mains in the winter.

The explanations given so far are just nonsense. Ask this question:

Do the generating companies prefer you to use power off peak during the nighttime or do they prefer you to use power during peak times?

Well the answer is that they obviously want you to use it off peak which is why off peak costs 4.62p/kWh and peak costs 12.17p/kWh.

SolaX is totally bonkers setting up the storage with off peak charging disabled. I definitely won't be purchasing from them.
dwilliams
dawkinsp
This is a new install and will not show on google yet. (You are looking at the neighbours)The batteries are 2x BYD B-Plus 2.5 kwh Lithium Ion Battery.2.7Kw composed of 9 panels LG300S1C-A5http://www.lg.com/us/business/solar-panel/all-products/lg-LG300S1C-A5The batteries are now active (27th June) so you will get a good idea going forward how it plays out.The second bit is a bit of wishful thinking based on some research. The ‘full’ spectrum panels that will pop up in a few years will see 3x the performance of those currently available. With that and some form of long term storage based on efficient hydrogen production and a 4Kw fuel cell etc.

Thanks for the clarification. Over the year (ours was installed May 2016) I have noticed a few “issues” which I really need/want to understand. A quick glance at your dashboard suggests that your installation may experience similar issues. Don't get me wrong, I am delighted with the way the SolaX X-Hybrid works and without doubt we have saved money over the last year. I think it's best to deal with each issue separately to start with.

SolaX recommends that the minimum battery discharge setting should be 20%. The main reason for this is to maintain sufficient battery capacity should you need to switch to EPS mode during a power cut (do you have EPS mode and have you used it?) From reading up about the type of Lithium Ion batteries we have I see it is recommended that they should NOT be totally discharged so that may be another reason.

Now the issue I have occasionally seen is that the battery (3 physical = 1 logical) does indeed stop discharging to power the house at 20% (exactly what time this happens will depend on how good a generating day it has been) but then it will continue to gradually discharge and the lowest I have seen it is 9%. Presumably you are familiar with the way the SolaX X-Hybrid increments the generation meter as it discharges the battery? … they call it “deferred generation”. What this means in practice is that discharging the battery from 100% > 20% clocks up the generation meter by the appropriate kWH which is fine. However, I have noticed that when the battery continues to gradually discharge below that 20% threshold that energy is NOT clocked up on the generation meter. That's 10% of previously PV generated energy lost/leaked?? One of the selling points of the SolaX X-Hybrid is that it has no effect whatever on the FIT income you receive before/after (in the case of a retrofit like mine). In view of this occasional (a couple of times a week) “lost/leaked energy” I beg to differ. I have 2 PV systems in close proximity … ours 3kWH (12 panels) and our son's 2.5kWH (10 panels). In the few years up to May 2016 i.e. before our SolaX was installed it was almost guaranteed that our larger system would generate proportionally more than his smaller system. In the last year this has never been the case and I can only assume it's this unaccounted for leaked power that explains the difference.

I've had a quick look at your SolaX graphs and see that on some occasions your battery has gone down with no obvious explanation e.g. 14/5/2017 0245 it was at 42% then by 0320 it was at 0%. There may be more instances you have noticed. Looking forward to your thoughts on this issue.
dawkinsp
Do not look at battery use before 27th as the BMS was not active and it was incorrectly being treated as Lead acid based on the voltage. This has now been corrected so the capacity and the charge / discharge will be correct.

You will get self discharge of a battery so if it is sitting there for any length of time without being recharged you will see it drop below 20%.

You will get loss on charge and discharge, nothing is 100% efficient.
So you may have a loss of more than 10% compared to feeding into the grid.
dwilliams
TerFar
I've been keeping a close eye on the developments and cost of battery storage and it looks like it is now beneficial. My only disatisfaction with the SolaX is that we cannot charge the batteries from off-peak mains in the winter.The explanations given so far are just nonsense. Ask this questiono the generating companies prefer you to use power off peak during the nighttime or do they prefer you to use power during peak times?Well the answer is that they obviously want you to use it off peak which is why off peak costs 4.62p/kWh and peak costs 12.17p/kWh.SolaX is totally bonkers setting up the storage with off peak charging disabled. I definitely won't be purchasing from them.

Hi TerFar, I totally understand and share your frustration about not being able to charge at off-peak times/prices to use during peak times. I have mentioned before that while SolaX do disable this by default it's just a setting which YOU can enable and set the charging times to accord with off-peak prices. The issue inhibiting us FIT users is the point at which their X-Hybrid system clocks up the generation meter. If you don't have a FIT then there is absolutely nothing to stop you doing exactly what you want. If you do have a FIT then you can still do it but risk being disqualified. If only “someone” would get a DC Generation Meter MID certified so that your PV generation could be recorded between panels & inverter then problem solved. This is the sort of feedback that Ofgem need as they try to move forward so that regulations & technology work in harmony.
dwilliams
dawkinsp
Do not look at battery use before 27th as the BMS was not active and it was incorrectly being treated as Lead acid based on the voltage. This has now been corrected so the capacity and the charge / discharge will be correct. You will get self discharge of a battery so if it is sitting there for any length of time without being recharged you will see it drop below 20%.You will get loss on charge and discharge, nothing is 100% efficient.So you may have a loss of more than 10% compared to feeding into the grid.

I appreciate that any battery will self discharge and the drop of 10% I have previously observed is the most extreme earlier in the year. However, last night until just after 2000 my battery was steady at the 20% threshold then suddenly a blip in the graph and it goes down steadily to 14% until just before 0900 this morning when it starts to recharge. I feel that a drop of 6% (of the capacity of a 7.2kWH battery) over 13 hours seems a bit steep. As you say, “if it is sitting there for any length of time” yes, but just overnight??
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