So to really ensure my ev is powered by solar and off grid my set up is this?

Solar panels (DC) > battery > wall mounted charger (ac) > ev?

If I don't wanna spend on a battery

Solar panels (DC) > converter > wall mounted charger (ac) > ev?

Second set up only allows me to charge during day time only right?

Hi sifus. I was proposed bifacial solar panel for a tiled rooftop installation. However, based on my understanding, to maximize bifacial gains, you would need to install the panels on an elevated racking system to allow the back panels to capture light. Would I be better off installing non bifacial panels?

No, during daytime we also get from the Grid, our solar energy is exported and we import the Grid energy. Hence they offset during daytime but not the night time when we have surplus from daytime generation.

The solar db is connected to our house db. It’s not connected to the Tnb grid directly. 

So it will be self consumption first, then extra will be sent out. This is confirmed.

Yes, u need to have Tnb supply to start generation. But that only to start. Once ur system produce enough, u don’t draw from Tnb anymore.

Also, one thing to consider. Ur system could be producing 1-2kw in the morning, before it peak, and at that time if u on aircond, maybe ur usage is more than 1-2kw, so the balance they draw from Tnb.

But when u peak at 10-12kw during afternoon, and ur appliances only run about 1-2kw, u will send the extra to them. 
So the net import figure from the bill is from this kind of usage.

If our inverted can do it, why can't during blackout period? Simply because our inverter cannot cater for direct usage.

Show me where its said this "Yes, u need to have Tnb supply to start generation. But that only to start. Once ur system produce enough, u don’t draw from Tnb anymore. "

I connect them to my 2nd floor DB ... So my ground floor not using solar energy? They do travel backward to the meter?

Can't I just connect solar panels to the ev charger without informing tnb/sesco? By my calculation to charge an ev I need 32 solar panels?

No , you have to consider whether your inverter is a 3 phase inverter or a single phase inverter.

Most installer want to sell cheap , and consumers do not know , so they only use single phase inverter. If it is single phase inverter, the inverter will only offset one of the phases. It does not offset all phases.
The other 2 phases will not be offset during the day time and continue to consume from the grid.

That's why when the1500kwhr ruling came out , some of the solar owners were charged because they were still using 1500kwhr from the grid.

The 1500kwhr, if you get it from the grid you will be charged extra. They don't calculate nett Export -Import , they just calculate what you get from the grid.

To the solar owner, in case you would like to monitor your solar generation, grid, and load in realtime (mobile app only), you can consider installing this bidirectional energy monitor (https://expo.tuya.com/product/1105297 , from Shopee or Lazada).  NOTE: This is for a single-phase house.

I will recommend an energy monitor with 2 CT, where the 1st CT (current transformer) monitors the TNB input (as Channel A), while the 2nd CT (as Channel B) can either monitor your load or solar wire (subject to the complexity of your wiring). For simplicity, monitor the solar AC input. Channel C is derived from Channel A and Channel B.

For example:-
Channel A: TNB input
Channel B: Solar input
Channel C: Channel A + Channel B = Load/Consumption

NOTE: The above works well if both TNB and solar input meet in the same DB box; otherwise, you will need 2 units of energy monitors, for example, one for the TNB on the ground floor and a second monitor unit on the 2nd or 3rd floor where your solar inverter is connected.

For smart home users using Home Assistant, this energy meter does not give valuable (limited) data for plotting graphical energy flow between grid, solar, and load.

Actuallu it’s possible to offset all 3 phase with single phase inverter. 

Not sure if this is possible with string inverter. Micro is possible.

a micro inverter does not offset all 3 phases at the same time.

but you can assign different microinverter to different phases , but a single microinverter DO NOT offset all 3 phases a the same time.

No , you have to consider whether your inverter is a 3 phase inverter or a single phase inverter.

Most installer want to sell cheap , and consumers do not know , so they only use single phase inverter. If it is single phase inverter, the inverter will only offset one of the phases. It does not offset all phases.
The other 2 phases will not be offset during the day time and continue to consume from the grid.

That's why when the1500kwhr ruling came out , some of the solar owners were charged because they were still using 1500kwhr from the grid.

Then you go and whack your solar vendor/installer, they are the expert and not advising you properly.

Then you go and whack your solar vendor/installer, they are the expert and not advising you properly.

Usually they will use the correct inverter according to the phases. Later no saving kena diao from customer ler.

Nope.  Most inverter sold now is single phase inverter connected to only a single phase in a 3 phase system.

Nope.  Most inverter sold now is single phase inverter connected to only a single phase in a 3 phase system.