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Typical Electrical Load Expected for Precast Parking Structure 1

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KootK

Structural
Oct 16, 2001
18,183
I'm structural but I'm being asked to ballpark the electrical load required for a parking structure that I'm involved with. Anybody able to provide some numbers on a per square foot basis etc for something like that? The scale of the structure will be similar to that shown below. Pretty small.

C01_ztjicn.png
 
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Lighting and HVAC would normally be the largest loads - at least in the past. Lighting is generally minimal - a couple of watts/sq ft. HVAC is normally just ventilation, but you will need to get some clarification. BUT ..... You will need to ask if there should be provisions for EV charging stations. This will substantially increase the electric power demand. Maybe you should get some mechanical and electrical support?
 
Some places have engine heater outlets; maybe an elevator, some allowance to operate an automated gate system, maybe an occupied booth?
 
The Canadian Electrical Code will give a Watts per square foot meter basic load.
To that add a load for block heater receptacles (see the CEC) and any other loads such as elevators etc.
Elevators might have a peak load representation
See the code for any applicable demand factors.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
There will be a single bay elevator.

There will not be an occupied booth.

There will be a dozen or so EV stations.

There will be no M&E support for this phase. PM decision, not up to me.

Thank you, all, for your help.

 
KootK
I haven't updated my copy of the code since I retired.
I did not quote actual rules and/or tables as there may have been changes and I didn't want to lead you wrong.
There have been changes but I don't know what I don't know. grin
EV stations? I don't know but that field is a work in progress.
You need current information.
It may be that the minimum allowable service will be adequate, but to assume that may become expensive.
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
EV charger station load is all over the map -
[ul]
[li]Level 1 ~2kW[/li]
[li]Level 2 ~19kW[/li]
[li]Level 3 ~50kW and up[/li]
[/ul]
Screenshot_from_2023-12-14_05-50-18_ogmyhc.png


Check with the electric utility, they may have a program to provide service and chargers as a service.

A few 50 kW chargers and you have a substation.
Selecting an appropriate diversity factor for chargers is going to be a problem as they can be expected to have significant periods of simultaneous high load often enough to matter, and also periods of inactivity.
 
For most kinds of occupancies Washington state is adding a requirement for 10% of parking to have EV chargers plus an additional 20%-45% of parking must have have conduit/raceway/panel capacity preinstalled. The electrical room must be sized to for charging at 40 amps at 208/240 V per EV charger, unless there is an automatic load management system in place that reduces the required capacity to 16 amps per EV charger.

Even if you do not build to Washington's requirements, hopefully you can include provisions for conduit/raceways and space in the electrical room that will make it feasible to retrofit additional EV chargers over time.
 
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