Every time someone starts planning an EV charging station, the first question is AC or DC. It is the right question, but it is worth understanding what it is really asking, because the answer depends on where the AC-to-DC conversion happens — and that single detail drives the cost, the speed, and the grid requirements.
The one detail that decides everything
An electric car battery stores DC. The grid delivers AC. Somewhere in between, something has to convert one to the other. That “somewhere” is the entire difference between AC and DC charging.
AC charging piles — like the 7kW GHCAC-7 — do not convert anything. They pass grid AC straight to the car, and the vehicle’s onboard charger handles the conversion. Because the conversion lives inside the car, the pile itself is simple, small, and cheap.
DC charging piles — like the GHCDC-160 — do the conversion inside the pile and feed DC straight to the battery, bypassing the onboard charger entirely. That is why they can deliver so much more power: the car’s built-in charger is no longer the bottleneck.
The numbers you actually care about
| AC pile | DC pile | |
| Typical power | 7-22kW | 30-720kW |
| Time to add 60kWh | 8-12 hours | 15-90 minutes |
| Where conversion happens | In the car | In the pile |
| Equipment cost | $500 – $2,000 | $10,000 – $60,000+ |
| Grid supply | Single or 3-phase | 3-phase, high capacity |
Notice the cost gap. An AC pile costs roughly the same as a good laptop. A DC fast charger costs as much as a small car. The price difference is not markup — it is real hardware. Power electronics, transformers, cooling, and metering all live inside a DC pile.
When AC makes sense
AC charging is not a compromise; it is the right tool for the right situation. Choose it when:
- Cars will sit for hours anyway — hotels, workplace parking, residential overnight.
- Budget matters and you need many points, not fast ones.
- Your site only has single-phase or limited 3-phase supply.
- You want the lowest-cost way to add a dozen charging spaces.
A bank of 7kW AC piles at a hotel or office park is the highest-efficiency use of a modest budget. Drivers are there for hours; they do not need speed.
When DC earns its price
DC fast charging exists for the situations where an hour of waiting is a deal-breaker:
- Shopping centers and highway service areas where drivers expect a meaningful charge in under an hour.
- Commercial fleets — taxis, buses, logistics — where every minute a vehicle sits charging is lost revenue.
- Any site where you are paid per kWh and want to maximize throughput per parking space.
A 160kW dual-gun DC charger can serve two cars back-to-back and keep a busy bay busy. That is the business case in one sentence.
What the total cost really includes
The one thing we repeat to every charging station client: the equipment sticker price is a fraction of the project. A DC fast charging station carries real costs around it:
- Grid connection. High-capacity 3-phase supply is not free, especially in remote areas.
- Civil works. Foundations for floor-standing units, cable trenches.
- Transformer. Big DC banks usually need a dedicated step-down transformer — this is where a prefabricated substation can bundle several jobs.
- Power management. If you do not manage peak draw, the utility demand charge will eat your margin.
That last point is where a flexible charging stack earns attention. A stack shares power across terminals and lets you add modules as demand grows, so you do not over-build the grid connection on day one.
The practical answer for most sites
For most commercial locations, the answer is not AC or DC — it is both. A bank of low-cost AC chargers for the long-stay parking, plus a smaller set of DC fast chargers for quick-turnaround customers. That mix balances cost, throughput, and grid capacity better than going all-in on either one.
If you are building a dedicated fast-charging hub, plan for the full power chain — grid, transformer, distribution, and chargers — as a system rather than a row of boxes. It is cheaper to build that way, and it is far easier to maintain.
Planning a charging station? We can help you work through the mix.
Related Articles
- EV Charging Station Overview
- How to Choose the Right EV Charging Station Equipment
- How to Build a Commercial EV Charging Station
About the Author
GOHO Engineering Team — With over 15 years of experience in EV charging infrastructure, our team designs and produces transformers, switchgear, and charging equipment for DC fast charging projects worldwide. All GOHO products comply with IEC 61851, IEC 60076, and IEC 61439 standards. Learn more about GOHO.
Last Updated: September 2026