Car owners are being encouraged to swap their combustion engine cars for zippy electric vehicles (EVs) as a way of reducing emissions and being friendlier to our environment.
That is easier said than done, for the move towards EVs requires plenty of support. Tax incentives, the availability of affordable electric models, and of course, lots of charging points, will influence the take-up rate.
Much attention has been given to charging stations. The Government wants every HDB estate EV-ready by 2025, and 60,000 new charging points across Singapore by 2030.
The Land Transport Authority is launching a tender for 12,000 new charging points across nearly 2000 carparks. It has also introduced a new national charging standard, TR25:2022, which will allow providers to upgrade the charging limits for fast chargers.
Installing new charging stations sounds simple, but it can actually be complicated. To find out more about this, Torque sat down for a chat with Muhammad Khairul bin Mubarak, SP Group’s Deputy Director of Sustainable Energy Solutions.
Muhammad Khairul, who is a Professional Engineer, tells us about the processes involved and explains why installing charging stations isn’t as straightforward as just plugging them in.
How does the process of installing charging stations begin?
The landlord or property owner will either call a tender or appoint a provider. For commercial properties, the landlord would be firms such as CapitaLand or Frasers Property.
After a tender is secured, the agreements are signed and other necessary approvals are secured. We will discuss the placement of the charging points and cable routing. All of these must be in writing.
Next, we must do site surveys and seek permission from the building’s Licensed Electrical Worker (LEW), who handles the property’s electrical matters. The LEW will indicate the available electrical capacity.
The charging points aren’t connected on the spot, but are powered by cables that run from the building’s switch room. To connect them, an electrical shut down must be performed. We work closely with the LEW to find a suitable date to avoid impacting downstream users.
If possible, we’ll try to dovetail our installation with the building’s annual shut-down to avoid any inconvenience.
How do you determine how many charging points can be installed?
This depends on several factors, but the main ones are the landlord and electrical capacity. Every property has excess capacity available because property owners have to anticipate future needs.
Let’s say there is a 100A (ampere) breaker. From there, we can calculate how many chargers can be supported, which we will then propose to the client.
Installing more chargers is more expensive. But cost aside, not every landlord wants to designate so many parking spaces for EV charging. SP Group typically proposes four (two AC and two DC) chargers, which is acceptable to most property owners.
On average, how long does installation take?
It’s usually between three and four weeks. Let me explain why.
First, let us assume that we’ll be installing a typical configuration of four charging points (two AC and two DC). Let’s also assume that the equipment (the chargers and cables) is available and that the electrical shut down can be performed when needed.
Now, the main factor determining the installation speed is the distance between the switch room and the location of the charging points. We want the parking spaces closest to the switch room, because this means shorter cables and lower costs. Let’s say we get these as well.
The next issue is working hours. Shopping malls are busy places. Most times, we can only start work after they close. We need space for our tools and materials, so we will occupy other parking spaces, too.
At some sites, we only begin work at 10pm or even 11pm and end at around 4am. After the shut-down is performed and the chargers are powered, engineers then conduct user acceptance testing (UAT) and iron out any kinks.
How would you install chargers in spaces such as surface carparks?
It’s the same – we still need to locate the switch room first. But for surface carparks, it is usually relatively far away. However, we have not had to draw power from an overground (OG box), which are those grey metal boxes you see along the street.
In buildings, power cables can run through the ceiling. But in a surface setting, we may need to excavate to lay the cables, which complicates things.
Engineers must perform cable-detection works to avoid damaging existing cables or pipes. Only when these have been properly mapped can the excavator be brought in to start digging.
What happens if a customer wants fast charging at home, but the power supply in his area doesn’t support it?
Here’s the thing: We don’t encourage the installation of fast chargers in private residences even if it is possible.
Based on driving patterns in Singapore where motorists average 50km a day, you don’t have to charge your EV daily.
Let’s say you have a 7.4kW AC charger in your house. If you plug in your car the moment you reach home, it will be fully charged by the next morning. A slow charge overnight is enough, even if you drive 300 or 400km a day.
Hardware- and capacity-permitting, we could install a 22kW AC charger. But if the EV you’re driving can only accept 11kW AC, then there’s no point.
Let’s say my residence can only support 3.7kW AC charging. Is there any way to upgrade this?
You’ll need to hire an LEW to conduct checks, and then write to SP Group to ask for a power supply increase. The requests are granted on a case-by-case basis.
If you were to install chargers in a HDB carpark, who would the stakeholders be?
The main stakeholders are HDB and our LEWs. They will advise where we can locate the chargers and how much capacity we’d be given.
Based on the installations done by Charge+ and ComfortDelGro in HDB multi-storey carparks, the chargers are not on the lower floors. As you’d imagine, most residents wouldn’t be happy seeing charging spots on the first and second levels.
As the provider, does SP Group have more say over the location of the charging stations?
It’s always a mutual decision. Of course, we want spots closest to the switch room, but the landlord will have other considerations.
Installing charging points in older HDB estates is tricky because EVs and chargers were never considered to begin with. But in new estates, such as Tengah, charging points are part of the plan. Additional capacity has also been factored in.
Can you still install chargers in properties with power constraints?
Yes. We will employ smart charging, which utilises an algorithm to ensure that the charging points share the total available capacity.
Suppose the capacity is only 64A, and one car can take 32A. If there are two EVs being charged simultaneously, then each one takes 32A. Now, to enable four EVs to charge, smart charging would split the load so that each car gets 16A, not 32. That way, the power supply won’t “trip”.
Of course, how much each EV gets also depends on its state of charge. A battery that’s almost fully charged won’t need as much power as one that’s running low.
What makes up the bulk of the cost of charging points?
Cables are very expensive. The longer the distance, the more cable needed and the higher the cost. Plus, the further away the cables are from the switch room, the larger the voltage drop.
To mitigate this, we have to include additional sets of cables, which will really drive up the cost. DC chargers, with their higher power, require thicker cables, which are more expensive.
Will the SP Utilities app eventually allow EV drivers to reserve charging points?
The current demand for chargers isn’t high enough to implement such a feature yet. But it is something that the team is studying. It’s either this or an anti-hogging feature.
SP Group’s charging costs are uniform across Singapore. Will this change in the future?
I won’t rule out a change if the demand for charging stations increases. We could have different prices for peak and off-peak hours, with the latter being cheaper, of course.