No no, both r premium micro, 51K with BESS, 32K without.

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RM39,000/RM458/12 = 7.1 years ROI. Correct.?
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Hybrid inverter size?

Battery cell price already gone up 10% in China but I think local complete unit price will be absolved by importers so don't expect it to go down much.

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My bad, you are correct. Thanks for the correction. Eg .......


= a 12.4kWp solar system produces 1,300kWh per month = 43kWh per day but the BESS/battery  can only store 32kWh (usable = 30kWh.?) during daytime (for usual use at night) = about 10kWh per day exported to TNB at RM0.21 per kWh, and 3kWh self-use during daytime.

Also, the Tesla Model 3 AWD has a 75kWh battery = needs about 50kWh to charge from 10%-80% overnight but the BESS/battery has only 32kWh (usable = 30kWh.?) stored from daytime = about 20kWh or more will need to be imported from TNB at RM0.40 per kWh.
....... So, an EV car will set back the above ROI from 7 years to about 8 years. Correct.?

Under ATAP, for most households who use most of their electricity at night, the above 12.4kWp solar system with BESS that costs RM45k, can save; ...

- BESS/battery savings per month = 30kWh X 30 = 900kWh X RM0.40 = RM360 ...
- Extra solar E exported to TNB per month = 10kWh X 30 X RM0.21 = RM62 ....
- 3kWh self-use during daytime per month = 3kWh X 30 X RM0.40 = RM36

... can save a total of about RM458 from their monthly TNB bill.

ROI = RM45,000/RM458/12 =  about 8.2 years. Correct.?
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I don’t recall  Bess will be 6years in my calculation.  It’s about 7.5-8 years.  Coz the saving really fluctuates especially when u have afa. Maybe in best case scenario it will be 7 years. Or if u do those diy stuff with cheaper parts.

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According to the above Solar company, Trdenergy, it's more like your calculation of around 6 years ROI may not work like 90% NEM (after contract ends) and the new ATAP.
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The summary is in the highlighted and/or bolded parts. Please read.
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So, under ATAP with BESS, if the household uses most of its electricity (90% or more) at night, which is most households, the ROI for the above RM39k Solar system is about 7 years, ...
.... but if the household uses some of its electricity (>20%) at daytime, eg got elders at home, the ROI is about 6 years. Correct.?
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AFAIK, most households with Roof Solar use most of their electricity at night, eg cooking dinner, bathing with water heater, using Internet, TV, computers, etc in aircon living room, charging EV car overnight, sleeping in aircon rooms, etc. Correct.?
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For battery, a 32kwh battery will theoretically provide 960kwh at night. But after factoring 90% DOD, it’s only about 860kwh, and also there are days when you ar unable to fully charge due to low production.  In good months for example, there will be 15% - 20% of the days when u get lower than expected yield and unable to fill up ur battery. This hasn’t include the conversion efficiency which will eat up a few more kWh along the way.

Plus, if battery is fully charged by noon on good days, all those extra generation will only be paid 20cent (if under atap) or go to waste if not under atap.

Then we have negative afa on certain months. Electricity tariff is lower with the new calculation, so it will also drag the ROI a bit too.
For example, in the past , the before solar and after solar bill has a bigger difference, but even under nem, the gap narrow a bit.

The good thing about the Bess is the possibility to get the eei incentive as the import is lower significantly compared to nem.

The best scenario for ROI  will be those with over  1500kwh usage, and with the system will be able to reduce the import figure to just a few hundreds units. If your bill is around this usage, then it’s possible to have quicker ROI as what u mention, (6years).

I would think 6 years is always on paper. Expect some delay in ROI coz lots of factors might affect it unlike nem, which is quite straight forward.

It’s not that straight forward. Coz you can’t total the 100kwh jsut like that. It’s on daily basis. If you have more days of lower generation, expect to be hit with higher bill. A 100kwh could be just due to 3 day low yield but also it can be due to 6-7 days of low yield. This could also affect.

To achieve 500 saving, it would be easier if usage is above 1500kwh, coz ur bill before solar is based on 37 cent per kWh excluding other charges instead of 27 cent. This is also one thing that can speed up the real ROI.

Going solar has been a long term commitment. Even under nem, it’s about 5-6 years. So Bess at 7 years is very acceptable. Who doesn’t want free solar setup and battery from Tnb right? Instead of jsut paying for electricity.