Bescom Lt6 connection for home charger

 

Once we bring our EV car home, the next logical task is to get a charger installed at home. In most cases the sanctioned load in our home may not be sufficient to meet the needs of the car charger and hence we will have to enhance the sanction and change the electricity meter along with it. Thankfully for those of us in Bangalore, Bescom has a special tariff plan - LT6 which offers electricity at a flat & lower rate for EV owners.

Like most EV owners, I too got a 7.2kW charger. The sanctioned load on my existing connection was just 2kW. So I had a choice to enhance the existing load or take a separate LT6 connection. I decided to take a separate LT6c connection and in this post I am sharing my analysis of the difference in cost between the two decisions. Getting the separate connection costed me about 35,000 in total including the deposit, new meter charges, material etc. Further below, you will find the process I went through for getting the connection as well as contact info for my electrical contractor who did the job for me. But first, the math to see if a dedicated LT6c connection is worth it.

Price comparison:

Enhancing the existing connection means a single connection of 10kW, which is 2kW for existing house load plus a 8kW additional load because of the charger. Although it might be possible to enhance the load to 8 or 9kW in total, it will mean you have to shut off all major home appliances such as heater or A/C when charging the car. Hence I was recommended to enhance to 10kW and that is what I am using for calculation. The fifth column in below table '10kW LT2 connection' is representing this number.

The fourth column 'Lt6c dedicated + current Lt2' represents the total cost incurred by both the 2kW home connection plus the LT6 dedicated connection.

To make the comparison close to real life, I am making the following assumptions :

- Car usage of 25kms per weekday and 25kms over the weekend. This would all be city usage which will require charging at home. This translates to 150kms per week or 600kms per month.

- Economy rate of 6km/kWh which is an acceptable average I have seen when driving within city traffic.

This translates to 100kW or 100units consumption per month for charging the car. House consumption column in the table below shows various consumption levels and reflects what we see in our bill. The number would naturally be higher in summers and lower in winters. But the idea is to get an idea across the board.

I have used the slabs and pricing published by Bescom here, to do the below calculation and also verified the math against our last few months bills to ensure the calculations are correct.  I have also included FAC charges applied by Bescom (fixed per unit cost) but have not added taxes. 

The table above clearly shows having a dedicated LT6 connection results in overall lower cost even if house consumption is very low at 40 units per month. Indeed the difference only gets larger if the house consumption is larger. Extrapolating the same trend to increase our car usage, the delta gets larger as well. In summary, higher the consumption lower is the price for us with the dedicated LT6 connection. Ofcourse there is an initial cost for getting the new connection, but there will also be an initial cost for enhancing the existing connection's sanctioned load - deposit for the additional 8kW sanction plus the new meter. My electrician estimated that the cost would not have been less than 30,000 for it. So, the difference of 5,000 would be broken even in 10 months. Assuming Bescom continues to have the same pricing and rebate for LT6c.

To understand these numbers a little more, below is how I arrived at them. The first table below is calculating each of the fixed and variable cost for a 10kW sanction load. Fixed cost is the same throughout since its dependent on the sanctioned load (100 for first kW and 110 for each thereafter). Variable cost or energy consumption cost increases based on slabs and hence it can be seen increasing exponentially.

The second table below is the same view but for two connections - The existing LT2 for home use and the LT6c for car. Variable or energy consumption cost is the same for LT6c as there are no slabs for LT6c connection. Its a flat rate of Rs5 per unit.

Process of getting the separate LT6c connection

My electrical contractor did it very easy to get the connection by taking care of most of the leg work necessary. The only amount of work I did was an initial enquiry at the Bescom office to get the connection. I was told by someone that the LT6 connection is only for commercial uses. Then a friend at Bescom informed me about an amendment circular (link) which showed that Bescom would give it for individuals too. I then contacted Arasu, my electrical contractor, and asked him to do the necessary work. He called me at frequent intervals to obtain the necessary documents such as my existing Bescom bills, house floor plan and to get the signatures. Then, once it was sanctioned he gave me the papers requesting deposit to be paid. I got the DD from bank. He then took care of rest of the work to do the wiring as per specifications given by the charger company, get in inspected and approved all the way until writing the RR number on the new meter. I am completely happy with Arasu and would recommend him to anyone. I am sharing his number below.

Arasu - +91 98451 42475

I am yet to get my first bill on the new connection, but am confident it will match my calculations above. Unless Bescom changes their tariff and removes the reduced pricing on LT6c, I will be able to have a low running cost and overall lower cost.

 

Bengaluru to Kodaikanal

        By now it's evident that I love doing long trips with my new EV and I grab every opportunity to do so. With the car being a month old and having completed 2.7K kms already, it was time for the challenge of a much longer drive to Kodaikanal. This entire trip clocked about 1000 kms and charging stops made almost zero difference to the travel time. If you are planning to do a similar trip, ensure to read the route and planning sections along with the tips at the end.

Route:

Onward journey to Kodaikanal

Onward journey:

- Started at 5:30AM and made first stop at 7:15AM at Hotel Surya complex, Krishnagiri. I had 72% SoC left when I reached and charging was not strictly necessary, but I did it to be rounded. The food was good at Sree Saravana Bhavan. In 45 minutes we had finished breakfast and car was at 100%, thanks to the 50kW charger.

- Next was a quick coffee stop at 11AM at Saravana Bhavan, Sankagiri. Charged from 55% to 95% in 35 minutes while having coffee. This too was a 50kW charger.

- Third and a critical stop at Ganpat grand, Palani. Charged from 30% to 42% in 16 minutes. This was at 3:40 PM.

- Reached hotel kodai international at 6pm with only 5% SoC left.

I stayed at LePoshe Kodaikanal. They refused to allow charging. So after deciding never to visit them again, I charged at Zeon 24kW at hotel Kodai international.

Return journey to Bengaluru

Return journey:

- Started from Kodaikanal at 9:30AM with 94% SoC

- First stop at Adyar Anand Bhavan, Rasipuram at 2PM. Had reached with 26% SoC left. Charged to 96% in 56 minutes on the 50kW charger.

- Then did a coffee stop at 5:30pm at Hotel Surya complex, Krishnagiri. Charging was not critically necessary, so decided to use the 24kW charger this time and topped up from 45% to 60% in 22 minutes.

- Reached home with 28% SoC at 10pm after crawling through the Christmas Eve traffic win the city.

Charging at Hotel Surya Complex, Krishnagiri

Planning:

Planning this trip had the inverse problem - the problem of plenty. There are so many charging options along the Bengaluru - Kodaikanal route that I could choose the stops where food was good and also had multiple backups.

After multiple recommendations and discussions in the MG ZS owners WhatsApp group, I had kept two route options : 

Option 1 - Krishnagiri - Salem - Karur - Dindigul - Kodaikanal

Option 2 - Krishnagiri - Salem - Erode - Palani - Kodaikanal 

In both options Zeon 50kW at Hotel Surya complex was the first stop, with Relux 30kW at Hotel Alps residency as backup.

Then in option 1 :

Second stop was 50kW Zeon at Adyar Anand Bhavan, Rasipuram and backup was Zeon 24kW at Omalur which is 20-30 minutes before Rasipuram. Not the ideal backup plan but what was available.

Third stop for a top up was at Zeon 24kW at Subbanna hotel, Karur. Tata 25kW at Kaveri Tata Dindigul, which is 74kms away was first backup and Zeon at hotel temple City which was even further away and 30 minutes deviation was second backup.

Similarly, for option 2:

Second stop was Zeon 50kW at Sankari, with backup as Relux 30kW at Perundurai.

Third top-up stop at Zeon 24kW, in Ganpat grand, Palani without backup.

Given the no backup situation for Palani, the distance from Sankari and ghat climb of Kodai, I started with route option 1 in mind. Moreover, Relux app had a message that there was a maintenance and that charging would not be available that morning. So option 1 seemed ideal 

However, when nearing Salem we realised that we will reach Rasipuram at 11 which is too early for lunch. So, thought of making a lunch stop at Subbanna hotel Karur instead. But that charger was showing offline, so I made a split second plan change to head towards Sankari and then top up at Palani. All of which were showing available. The road was not very great, it went through small towns which cut down the speed and added to commute time.

Some learnings & tips:

1. Have ample amount of charge before starting the ghat climb. Atleast 60% or more. Account for a burn rate of 2km/kWh or less.

2. Route via Palani works better for onward journey, to start the ghat with plenty of charge. But also creates a critical dependency on the only charger at Palani.

3. Starting the return journey with 75% or 80% SoC might be better instead of near full charge. Regen will anyway push it to near full charge by the time of climbing down. Plus, regen 3 will help with breaking while climbing down. Regen doesn't work if battery is full and the vehicle keeps rolling.

Bengaluru to Agumbe - Seethanadi nature camp

Day 12 with the new car, 1K kms completed and first service was already done. We had planned a trip to Mantralaya. That would have been a continued temple run and couple of cousins wanted to go there with family. But that plan had to be changed due to ekadashi. The new destination was Seethanadi nature camp by JLR which is on the other side of Agumbe ghat. This trip was with 4 other cousins who are all ICE owners. So this was kind of an Agni pariksha for my EV on viability.

Route

Route to Agumbe from Bangalore goes via Sringeri, so this trip route turned out highly overlapping with the previous one. Infact we stopped at Sringeri in the morning for breakfast at holla's before continuing to Seethanadi. So, planning charging stops was not difficult as i had already done it last week. The changes from last week was that there was a new Relux charger at Shantigrama and i negotiated slow charging while staying at the JLR.

Onward journey : 

A stop at Relux Shantigrama right after Paakashala was not necessary. But we met another MG at paakashala who were returning from Mangalore, they said the new Relux at Shantigrama was not working. So we stopped to test out and report if there were issues. It was delivering only 20kW. 

Until here the journey was great and at par with a journey in any ICE car. May be a tad bit better on comfort, silence and pickup. The next charging stop brought in the impact to journey time due to EV. 

We had to do the critical stop at Gateway Chikmagalur. At the 24kW charger, going from 45% SOC to 100% took 1 hour and 21 minutes. We chose to take a nap in the car.

The drive through Agumbe ghat was fun and we gained 2% soc. (A seperate post coming up on the ghat topic.) We reached Seethanadi nature camp with 63% soc left.

They were accommodating enough at JLR to let me charge the car. The socket was far (~20ft) but my newly brought extension proved helpful. 63% to 100% SOC on granny charger took from 2pm to 11pm.

Return journey:

After starting from the camp at 100% , we drove through the rugged roads of Kudlu theertha falls and then reached Hariharapura for lunch at 67% SOC. We continued with the destination as Gateway Chikmagalur, but a reassessment during a coffee stop at Khandya cafe showed we could comfortably make it to Shantigrama. That would be a better choice for food.

We reached Sky bird Shantigrama at 12% SOC. But there was some issue with the charger. It would shut off immediately after charging starts and we had to move ahead after a couple of tries. Imagine if Relux wasn't there within a couple of kms distance, Phew!

The thankfulness to Relux soon turned into complaints! Isn't it human nature after all? Food is not great there, smell of grilling meat from Empire was pretty strong plus the charger was only delivering 20kW.

So we plugged out at 35% soc and decided to head to paakashala for dinner. It was 9:15 when we started from Relux and had to reach paakashala within an hour, since it closes at 10:30pm. So that meant a mad rush drive plus banian mode at stretches. We managed to reach Mayura at 2%soc and plugged in there since the 50kW at paakashala was occupied. We walked to paakashala for dinner while the car got charged and then after some negotiations, had the Nexon move to Mayura and we came to paakashala. Nexons can only take a maximum of 29kW, so the 50kW was being under utilised at paakashala until the swap.

We were able to pull in 49kW speed, charged until 95% and headed home. There were 2 Nexons waiting while we were charging at paakashala.