From taobao.
https://item.taobao.com/item.htm?spm=a1z0d....id=586611033726

I wonder the current trade war will affect the price of things in taobao or not? 

5kw panel + hybrid inveter + 48v150AH Lead Acid battery = 22k
Additional 48v500AH Lithium Iron Battery = 13k
Coming month : additional 4kw panel and hybrid inverter for the back of my house. Currently all my panels are at the front of the house and I just realized half of the year the sun rises from the back of my house.  Should costs about 15k

I use the power to do bitcoin mining. So the time of ROI depends on bitcoin price. My estimation should be around 6-8 years.
If bitcoin goes into crazy bullrun then ROI will be a lot more faster hahaha.

If I use solar to offset my TNB bill without mining, I will never ROI.

Another thing that can be done with the battery if TNB implement peak metering, charge the battery full during off-peak and use battery power during peak time. 

Hi, i'm new to this and don't know much about solar energy, i'm exploring solar panel for own personal use since will be moving to a new place. I contacted TNB and one of the contractor (Gsparx) got back to me on 6kw package for RM30,000. Potentially would give me RM250-350 of electricity generation in monthly basis. Can someone share with me the experience for installing solar panel? is it worth while in long term basis. What would be the maintenance cost after the warranty period. Anything that i should look out for ? thank you.

Well, the monitoring tool on the inverter doesn't have a good reporting function so I have calculate it using other method.
On average with the current 5kw panel and 48V100AH batt I manage to run 1600w of load 6 hours without using TNB.
Thats about 9.6kwh of generated power per day. Currently the sun rises behind the panel. Less effective 

The battery is usually full before 12pm, unable to absorb more power from panel.
I think when additional battery arrives the generated power will improve even more.
Additional 4kw not yet installed so not sure how effective it will be.

48v100ah, Average 1600w load, About 2 hours 10 minutes.
I setup inverter only use about 80% of the battery charge.

This inverter has higher efficiency because its design to work with 48 system (42v-58v range) only so optimization can be made.

Lithium Iron Phosfate battery are design to have 2000 cycle on 100% discharge rate. If you only use 80% discharge rate the cycle can go up to 3k+. These numbers are cycles the battery go through before their capacity drops to 80% of original manufactures capacity.
I am expecting at least 10 years for my LFP batteries.
BYD's LFP battery pack that use for home solar power storage has 10 year warranty up to 80% of claimed capacity.
Note:
This is not the normal lithium battery we use in our phone or torchlight. Those lithium use in phone is Lithium Cobalt Meganize and usually has about 800 cycles.

Btw lithium titanite (ya another type of chemistry) has up to 20,000 cycle but its quite rare to see it here. Works well at -30 degree cold weather.

which one? 50AH or 400AH?