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Installing charging in Multi-Unit Dwellings

Discussion in 'California' started by RandyS, Jun 23, 2018.

  1. RandyS

    RandyS Fan of Elon

    Jul 8, 2012
    San Diego
    I work in the Clean Transportation group at the electric utility in San Diego (SDG&E), and was asked to start a new thread with this previously posted information about the steps it takes to get charging installed in a multi-unit dwelling. Please let me know if you have any questions. Every installation is a little bit different, but there are some common threads...

    * Get approval from your condo HOA or your Property Manager to install a charger in your space. The goal is usually to do the installation in such a way that the energy used will be paid for on your own electric bill and not the HOA power. That seems to be a common misunderstanding by the HOAs; they think they will have to subsidize the installation. Once they realize that you're paying for everything, sometimes that makes a difference. If you need to refer to California Senate Bill 880 that allows you to install a charging station as long you meet certain requirements, that might be helpful. You can't move past this step until you get approval.

    * If the installation is one of the few very easy ones where a charger can be added to your existing electric service or meter, all that is needed is an electrical permit from your City before starting. This might be more applicable to a single family home than a multi-unit dwelling. In a MuD, usually the electrical panels for the units are installed up in the unit. So it could be several floors above the parking garage and not in a good space to install any new wiring for charging. So my experience is that usually a new second meter needs to be installed in the electric room near the parking garage for a charging station. That's the situation address by the steps below.

    * After getting approval from the HOA, have the SDG&E Planner visit the site for a meeting. I can help introduce you to the correct Planner for your address... It would help during this step if you have hired a contractor / electrician for the job and they can be present, otherwise the opportunity to ask questions to the Planner on-site is lost and playing catch-up later just takes more time.

    * At the time of the visit, the Planner will outline the process. He/she will be looking for specific materials later from you and your contractor. This is where I've seen many people stop, because the process seems a little difficult, but it really isn't if you approach the requirements methodically with your contractor. The gist of the steps is to ensure that adding this new charging load to your building won't overload the existing electric service / feed.

    * For this example, say that the building has a 4,000 amp electrical service. Your contractor will need to figure out what the maximum load is on the building for a period of time (with a clamp-on recording meter, for example). The purpose of this is to determine whether your building's panel and the electrical feed has the necessary capacity to install the charging station(s) or if the service is near capacity or even overloaded.

    * You'll need to decide what size of circuit you want to add for the charging station(s) (40 amps, 100 amps, etc.)

    * During the site visit, the Planner will be looking for a location that you can install a new meter since most likely it will be difficult to connect to your existing meter. In many cases, there will be a spare meter socket or two that can be used for new EV charging. If there are no spare or available meter sockets, then the job can get a little tougher. The new meter will be in your name and can be on one of the EV time of use rates so you can save money by charging in the midnight hours or other super off-peak times. Both your existing meter and your new meter would be aggregated on the same bill, and they can be on different rates (although you probably want to use one of the EV time of use rates for the car).

    * Here's the important part. After measuring the building actual load over time, the contractor/engineer will need to get the as-built electrical drawings for the building and add in your load for the new charging station(s), resulting in an updated one-line electrical diagram for the building. You would submit this to the Planner so they can write a "Service Order" for the job. Getting the as-built drawings and updating the one-line diagram can take some time, but this is routine for adding any kind of load to an existing building.

    * Once the Planner gets that information, they will study the utility side of the electrical connection and make sure that the infrastructure will support what you're trying to add. You can see that adding one EV charging station is easier, and adding a bank of 10 starts to get more difficult as you start to reach the capacity of the building's electric service. Once The Planner does their work, and if all is well, then the Planner writes the Service Order. The Service Order document is then used by your contractor / electrician to get a permit from the City, and once that occurs, then work can begin to install your charging station.

    In advance of doing this, during the process of interviewing and hiring a contractor / electrician, you may want to have them come out and evaluate the job in advance, check things out to see how far the run will be from the electrical room to your space, whether concrete has to be core-drilled, etc. I've seen easy jobs and I've seen really complex and expensive jobs, so it just depends on your situation. I had one customer trade/sell their deeded parking spot with another resident that was closer to the electric room so that the electrical run was easier. They recorded the deeds and made the transaction official, and that customer is now charging their Model S in their parking garage...

    Anyways, that's the gist of the process to install a new electric service...I hope it helps....
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