Electric Vehicle Charging Stations

Electrical Vehicle Charging

Recent news stories have shown agreement that the supply of and demand for electric vehicles (EV) is growing. Car and Driver even posted an article recently outlining all of the promises that car manufacturers have made regarding plans to create a variety of new EV’s, including hybrids, plug-in hybrids, EVS and hydrogen fuel-cell vehicles. Most manufacturers are working on new models, and one thing is for sure: the US will need a huge increase in infrastructure to provide enough electric vehicle charging stations to meet the demand for charging these vehicles.

Recently our clients have begun to think about installing underground infrastructure so that their building sites are ready to add charging stations at a later date. Today we’ll take a look at what is necessary for prepping a site for this use. 

What are EV Charging Stations?

Electric Vehicle (EV) Charging stations are similar to what a gas station is to traditional vehicles – they’re the means by which an electric vehicle ‘fuels’ it’s ‘tank’. Many EV owners charge their vehicles at their homes in the evening, but as adoption of these types of vehicles increases, there is becoming a need to have charging stations in publicly available locations for longer trips, or those who don’t have their own home or garage to plug in to for the purchases of charging their cars.

Currently, there are three levels of EV chargers available:

Level 1
A standard 110-120 volt wall outlet, like you would find in your home. This is the slowest way to charge a vehicle.

Level 2
These chargers are a 220-240v outlet, similar to the voltage that powers up the average household clothes drier. This is the most common way that homeowners charge their EV’s and it may require a full night of charging to complete.

Level 3
Also knows as ‘fast chargers’, ‘DCFC chargers’ and ‘DC Fast Chargers’, these are 400v or more and are the quickest way to charge an EV, sometimes in 1 – 2 hours or less.

In addition to the level of charging, there are different types of plugs on each vehicle which may or may not connect to every type of charging station.

Underground Infrastructure

Like other electrical components in a building, the EV charging stations require a hard-wired power source, which means that underground conduit must be installed to run wiring from the public power grid to each charger.

On a recent project that Perlo constructed, the owner wanted infrastructure in place to add EV chargers to their entire parking lot at a later date.  This required sixteen 4” diameter conduits be placed underground with many vaults onsite.  Nearly 5 miles of conduit runs through that one single site for future charging stations.

Such a large infrastructure installation, if installed at a later date, would require tearing out most of their parking area to complete. With the conduit run during the new construction phase, the owner will be able to minimize downtime and re-work when they’re ready to complete the charger installation.   

Construction Schedule Impacts

For new construction, the impacts to the schedule duration will be dependent on the quantity and location of the charging stations. However, the conduit does require additional trenching and this work can delay the installation of some critical path work items, such as curbs and sidewalks, finish grading and paving for parking lots. With proper planning, however, the work can be accounted for to minimize those schedule impacts.

For a post-project installation, the work will require saw-cutting, trenching, and placement of conduit, followed by backfill and re-paving.  The duration will be highly dependent on the number of stations being installed and the EV charger locations relative to the power source. To minimize schedule impacts, it’s best to know that EV charging stations are desired during the preconstruction phase of the work. This will allow for planning conduit routing, sizing of electrical gear and procuring an electrician that fully understands the needs of charging stations.

Optimal Site Conditions

The infrastructure for EV charging stations can certainly be installed on any site, but the complexity to complete the work will depend on the conditions of the ground that the contractor must work in. Because the conduit work requires so much trenching, an ideal site will be dry, with stable, or even rocky ground. Ideal site conditions make installation simpler and safer for the workers placing the conduit. If sites have unstable ground, such as in very wet dirt, or sandy soils, there are safety risks such as trench cave-ins, and a need for more dewatering procedures.

Power Requirements

The question of ‘how much power do I need’ for future EV stations is a complicated question. The technology for these stations is evolving and if an owner doesn’t plan to install the stations for several years, it’s possible that the power requirements at that time will be less than they would be today.

Another complicated factor about power for EV stations is ensuring that the local power utility has the quantity of power necessary for the site. The volume of power needed for an entire parking lot of charging stations is significant compared to a standard building. An owner will need to work closely with their utility provider to verify that it can provide the quantity of power they’re wanting or enter into discussions to achieve that power within a reasonable time frame.

Final Thoughts

The best way to ensure a successful installation of infrastructure for electric vehicle charging stations is to pre-plan the work very early in the design phase of the project. With pre-planning, we can work through schedule impacts, routing, and procurement of a qualified electrician for the work. Additionally, conversations with the local utility provider will be paramount to ensure that adequate supply can be brought to the site.

If you’re considering the installation of electric vehicle charging stations, contact our estimating teams now for more information.