Building wide load sharing for EV charging

[Sporty]

I'm looking for pointers to charging stations that can be configured as a group to not exceed the buildings available power. Either by reading the current buildings power load or by having a defined maximum value the EV charging network must stay below.

The setup is a condominium building with owner owned parking spots with individual power meters in the garage. So, each service could be wired to each owner’s meter. But each port would need to be managed in some way to avoid overloading the building.

Additionally, I’d rather not have a monthly subscription to such a setup. I know Charge Point has something but in addition to paying for each station they want 20/month per charging port. On one hand that doesn’t sound like a lot, but on the other if you don’t drive a lot in a month it could double the cost to charge. And some owners would need 2 ports given how the garage is setup.

 

[theflyer]

I'm looking for pointers to charging stations that can be configured as a group to not exceed the buildings available power. Either by reading the current buildings power load or by having a defined maximum value the EV charging network must stay below.

The setup is a condominium building with owner owned parking spots with individual power meters in the garage. So, each service could be wired to each owner’s meter. But each port would need to be managed in some way to avoid overloading the building.

Additionally, I’d rather not have a monthly subscription to such a setup. I know Charge Point has something but in addition to paying for each station they want 20/month per charging port. On one hand that doesn’t sound like a lot, but on the other if you don’t drive a lot in a month it could double the cost to charge. And some owners would need 2 ports given how the garage is setup.

So many variables. Here are the issues you need to resolve for your particular community. I have been unable to square the circle yet with respect to these questions:

• Do the EVSEs need to have authentication to prevent someone else from using the EVSE?
• How will the power be metered/billed?
• How far does the power have to be pulled? Is there a central EV panel from which each individual EVSE is connected to for power?
• What type of connectors are needed?
• Do all ports need to be 240v/50a or is a 110v solution possible?
• Is the community at the location willing to do any cost-sharing or does the burden for costs fall only on the EV drivers?
• What is the current need vs the likely future need? Can you accommodate ad-hoc solutions now and wait for a more holistic solution in the future?
• How many different types of users do you need to support (deeded parking spots, guests, first come, first served, etc.)?
• How important is it to have a solution that allows you to over-subscribe the power (e.g. have more chargers than would be allowed on dedicated circuits? More companies are offering services that load balance dynamically to allow oversubscribing by 4x or more.
• Where does management and/or the Board of Directors fall in terms of wanting to provide cost-effective solutions? In other words, do you have allies or are you just trying to force compliance with right-to-charge laws?

Would be interested in hearing what other questions people have had to deal with in trying to accommodate charging in high-density locations and how you squared the circle? What balance did you strike between keeping installation and monthly costs low for EV drivers vs. having simple managed services in which the EVSE are much more expensive and there are significant monthly costs?

 

[theflyer]

For a low-cost solution, check out: Orange Charger

They offer 110v/20A and 240v/20A solutions. No setup fees but they do add $0.05/kWh to cover their costs and profit. Not all EVs have a 240v/20a adapter for their mobile connectors.

Edit: These units don't load share but because the power draw is much lower, it is less needed, especially if the 110v/20A version is used.

 

[mociaf9]

Check out PowerFlex. Their core EVSE product is based around large installations of multiple stations with load-managing of the type you're looking for. I have no idea what their pricing/billing set ups are, but I know their tech can accomplish what you're looking for.

 

[owen.shift]

Tesla's own Wall Connector might just be able to do that. It says that Power Sharing for up to 16 units will be supported in a future firmware update... maybe someone else knows more about this?

Have a look in the user manual – Power Sharing starts on page 23.

 

[ATPMSD]

Tesla's own Wall Connector might just be able to do that. It says that Power Sharing for up to 16 units will be supported in a future firmware update... maybe someone else knows more about this?

Have a look in the user manual – Power Sharing starts on page 23.

Interesting, but the online guide for setting up Gen 3 power sharing supports only the a master and 3 slaves.

Wall Connector Power Sharing | Tesla Support

With Power Sharing, you can allow up to six 3 Wall Connectors to share power and charge multiple vehicles at once. Learn how to set up and troubleshoot Power Sharing.

www.tesla.com

 

[owen.shift]

Yes, currently it's up to 3 – but with a future firmware update, as I mentioned, it'll be up to 16. So the hardware is there; and we know that Tesla actually delivers on software.

 

[theflyer]

Check out PowerFlex. Their core EVSE product is based around large installations of multiple stations with load-managing of the type you're looking for. I have no idea what their pricing/billing set ups are, but I know their tech can accomplish what you're looking for.

I'll be emailing them today. Details are in short supply on their site.

Tesla's own Wall Connector might just be able to do that. It says that Power Sharing for up to 16 units will be supported in a future firmware update... maybe someone else knows more about this?

Have a look in the user manual – Power Sharing starts on page 23.

Yes, and it does authentication too. It appears you'd need another solution for monitoring power. There are some single-phase solutions on Amazon.com that would work although you'd have to double whatever they read.

Interesting, but the online guide for setting up Gen 3 power sharing supports only the a master and 3 slaves.

Wall Connector Power Sharing | Tesla Support

With Power Sharing, you can allow up to six 3 Wall Connectors to share power and charge multiple vehicles at once. Learn how to set up and troubleshoot Power Sharing.

www.tesla.com

True but you could have four blocks of four, each on a 50 Amp circuit. It is sub-ideal solution as you can't make full use of all available power across all 16 devices and the units have to be within physical wi-fi distance of each other but it might work in some instances.

 

[RTPEV]

Another option I just ran across the other day is Atom Power's PURPL EV charging system: PURPL™ Advanced EV Charging

I don't know whether this would support connecting each EVSE to the individual owerns' meters or not.

For that kind of capability, here is another option: DCC-9 EVEMS for Electric Vehicle Charging in Condos and Apartments

This unit effectively does load sharing at the individual unit level. I.e. it shares load with the end user's own unit.

 

[theflyer]

Another option I just ran across the other day is Atom Power's PURPL EV charging system: PURPL™ Advanced EV Charging

I don't know whether this would support connecting each EVSE to the individual owerns' meters or not.

For that kind of capability, here is another option: DCC-9 EVEMS for Electric Vehicle Charging in Condos and Apartments

This unit effectively does load sharing at the individual unit level. I.e. it shares load with the end user's own unit.

Thanks for these links. I was not aware of either.

The DCC-9 looks pretty cool for those with individual meters. Many older buildings do not have individual meters though.

I'm going to contact Purpl for more information. Their webpage is tantalizing but lacking in detail.

 

[RTPEV]

Thanks for these links. I was not aware of either.

The DCC-9 looks pretty cool for those with individual meters. Many older buildings do not have individual meters though.

I'm going to contact Purpl for more information. Their webpage is tantalizing but lacking in detail.

True. I reached out to Atom Power and asked them several questions about their ability to do load sharing. They got right back to me and confirmed that they did, even though it's not clear from their web site that it has this capability. In my mind, that is their killer feature and I hope that they eventually highlight it better on their site.

 

[ai4px]

Before wife and I both had tesla's I used a J1772 controller called SmartEVSE from netherlands. It came with a power measurement coil and could measure and adapt to loads on other outlets. For example, I got 32 amps when wife wasn't home, but when she plugged in I got the balance of what her model S wasn't using.

 

[Jeepxj]

powerflex.com can help.