Transformer Buyers for EV Charging Sites

On the ground

How EV Charging Sites use power

EV charging produces peaky load with long idle periods. Several DC fast chargers can ramp together as vehicles arrive from I-40 or I-85, then leave the transformer lightly loaded overnight. Fleet depots may instead concentrate charging after delivery trucks return.

Charger power electronics can introduce harmonic currents, while repeated charging sessions change winding temperature through the day. Before evaluating a retired unit, distinguish a transformer fault from charger trips, upstream voltage problems or an undersized service using relay records and service reports.

Local reality

The equipment you will find

Padmounts commonly serve outdoor charging plazas, with underground primary cables entering locked compartments and secondary conductors feeding charger distribution equipment. Record the primary voltage, secondary voltage, kVA and impedance from the nameplate; a 480Y/277-volt secondary does not establish the primary rating.

Dry-types may sit inside depot electrical rooms, while small substation units serve larger charging installations. Photographs should show enclosure vents, bushings, radiators and cable connections as applicable. For liquid-filled padmounts, include the fluid designation, bayonet fuse compartment and evidence of gasket leaks.

Around the site

The state's EV Charging Sites footprint

North Carolina's interstate corridor sites include charging locations along I-40, I-85 and I-95. Transformer removal at a highway-adjacent plaza must account for customers moving between chargers, restrooms and parking spaces.

A crane setup cannot assume the charging stalls are an empty laydown area.

Fleet depots in Charlotte, Raleigh, Durham and Greensboro present different access conditions from interstate plazas. Delivery vans may occupy the approach before morning dispatch. Check gate width, overhead clearance and the route from the transformer pad to the loading position before choosing lifting equipment.

Where it sits

The decision chain

The charging operator does not necessarily own the transformer beside its dispensers. Duke Energy or another serving utility may own equipment upstream of the service point. Confirm ownership against the service agreement and asset records before including any unit in a removal scope.

For customer-owned equipment, the facility director or asset manager typically coordinates with the electrical contractor and charging operator.

An EPC contractor handling a canceled depot build should provide transfer documentation, transformer identification and written release authority, rather than relying on the construction schedule alone.

On the ground

Schedule and regulatory pressure

A charging site's opening date may already be public while utility energization remains the constraint. That mismatch can leave an installed transformer unused or force a replacement decision.

Keep the utility's service approval separate from the owner's authorization to release the outgoing unit.

Removal must follow electrical isolation procedures and any applicable fluid-handling requirements. For an older liquid-filled transformer at a converted fleet depot, retain PCB documentation or arrange appropriate testing when status is unknown.

Coordinate the outage with charger shutdown controls and the serving utility.

Local reality

Removal logistics

A padmount can remain connected beneath its cabinet even after the chargers stop operating. Qualified personnel must isolate, verify absence of voltage and disconnect the cables before lifting. Protect exposed cable ends and confirm whether the concrete pad and grounding connections will remain.

At a busy corridor plaza, plan barricades around the crane and truck rather than closing only the nearest charger stall. Use documented weight and approved lifting points to select rigging, a spreader bar or a lowboy. Radiators and bushings need clearance throughout the lift.

Around the site

What to send us

Send a readable nameplate photograph, overall cabinet views and the North Carolina site location. Identify whether the unit is a padmount, dry-type or small substation transformer.

Include kVA, primary and secondary voltages, phase, fluid type where applicable, and the number of units being released.

Explain why the transformer is leaving the charging site: failed winding, charger expansion, canceled opening or depot redevelopment. Include ownership confirmation, available test reports, disconnect status and the required removal window. Access photographs should show charger islands, bollards, gates and the truck approach.