Hmm... I just try to work on the math problem.
Assuming a 5kw system produce = 450kwh (5kw x 3sun hour x 30 days) while a 7.2kw system produce 648kwh
Assuming your monthly usage is 750kwh (so you want your original 5kw solar power system to offset the higher tier and left you with 300kwh lower tier), in ringgit, your 750kwh cost RM320.25 (bill calculator from https://myelectricitybill.my/bill_calculator_domestic.html).
With a 5kw solar system, your usage will be 300kwh costing RM71
With a 7.2kw solar system, your usage will be 102kwh costing Rm20.20, so difference is Rm50.8 extra savings per month
So you spend additional 3k  for the system

Rm3000/50.8 = 59months = about 5 years

For a 5kw system, your monthly saving is RM249.25. The ROI is obtained after 20000/249.25 = 80.24months = 6.69months
For a 7kw system, your monthly saving is RM300.05. The ROI is obtained after 23000/300.05 = 76.65months = 6.39months (THIS)

So in short, for your system, it is better to get the higher capacity system because
Cost to generate 1kw in 5kw system is 20000/450kw = Rm44.4 per kw
Cost to generate 1kw in 7.2kw system is 23000/648kw = Rm35.49 per kw

Anyone else final bill before NEM get charged 8% tax for all?

1-600kwh should be tax free. Only 601 and above get charged 8%.

Meaning I was charged 8% for 1-600kwh as well.

I was quoted rm16k for 4.92kwp n 22k for 7.38kwp, a diff of 6k.

Btw 270 to 330.

So, after some comparison and my usage,

I went for 5.94kwp around 17k (trinasolar 0.495kw , solis 5kwAc, string)
so far the vendor response is very good and supportive.

ETA installation, early march

Hope some chinese dude comes up with a low cost breakthrough for home solar ala deepseek for the sake of humanity.  right now it is still too expensive to go green.

hi, anyone add on meter to track how much solar energy go out to TNB?
for huawei inverter, anyone done it ?

With so many advantages over string..and negligible price difference..why many still choose string over micro inverter?

I still don't understand why can't we put solar panels ground level. I have enough space for it

Guys..
My billing cycle supposedly start on 1st mthly…
Since I activated on 2/3, I’ve yet to receive my Mar statement per app. Kindly adv if this is norm for those whom just moved solar ..

just wondering does dc battery help can prevent clipping as the excess energy generated is stored? does huawei inverter has that function?

Thanks for sharing your insights. I read somewhere dc battery can receive the excess energy that the inverter can’t convert to ac.

I believe the clipping that you mentioned is inverter reaching the max AC power output

for example, your solar panel peak output is 6.5kwp, but inverter only can support AC output 5.5kw, at noon with clear sky, DC input power could reach 6kw, but inverter with 98% efficiency is clipped at 5.5kw ac output only. this is clipping

in this case, clipping is nothing to do with battery system. battery system is for system does not want to export energy to TNB, but want to store excess energy for night use.

what battery do Huawei inverter support?
worth all the afford for that extra KWH?

High guys, for the last two months, one of the micro inverters (PG Solar) experienced auto shutdowns. pg said it’s because of voltage surge (more than 270V). They refer TNB which came two days ago and they reaffirmed that the grid voltage is normal (238V). This auto shutdowns happened in the afternoon during peak Solar generation. TNB said it’s now for PG to solve the issue.
Anyone ever experienced similar issue? Tq

no, when high voltage, it keep restarting and shutdown, the whole day solar only produce less than 10kwh on sunny day, in normal time, i can get more than 20kwh per day.

in reality when solar panel go into grid, no people can different the current is from solar or other power generation.

when we send solar power to TNB, TMB will record it as green energy,

when they sell energy to commercial, they can sell higher price from the recorded green energy from us.

something like green energy certificate.

so company don't generate any green energy, but buying green energy certificate to proof they using green energy.

TNB is your big battery, why do you need battery? you only may need to consider battery after 10 years

if you want to have electricity during power trip, you will also need to make sure inverter is hybrid and wont shutdown if grid no longer supply power.