A fleet operator in Pune recently showed us a systems integrator's proposal for 15 planned AC chargers across three sites. It specified licensed SCADA software, an on-premise industrial server, Modbus-to-Ethernet converters at each site, VPN remote access, and an annual support contract. Total upfront cost: Rs 7.8 lakh, plus ongoing support. Implementation timeline: 10 to 12 weeks.
They were ready to sign when a colleague asked who would maintain the server when the Windows instance needed patching. Nobody had an answer. That led to a broader discussion about whether SCADA belonged in their operation.
SCADA's Original Design
Supervisory Control and Data Acquisition systems emerged from industrial automation in the 1960s and 1970s. Utilities, oil refineries, water treatment plants, and manufacturing facilities used them to supervise equipment across wide physical areas, with a central operator console reading sensor data and sending control commands in real time.
That heritage shapes the architecture. Field devices, typically PLCs or RTUs, communicate with a central SCADA server through industrial protocols: Modbus, DNP3, IEC 61850, or OPC-UA. The server runs on dedicated hardware, often in a hardened facility. Operators use a human-machine interface (HMI) showing color-coded physical infrastructure diagrams. Alarming, historian databases, and trend analysis assume a permanent, staffed control room.
This is not a verdict on SCADA as a category. It describes when another architecture fits better. SCADA remains right for grid operators needing real-time protection coordination at substation level, or hybrid solar-storage-charging sites where the inverter, battery management system, and chargers must communicate within milliseconds. It is not obsolete technology.
Why SCADA Misses Commercial EV Networks
A commercial EV charging operation with 10 to 50 chargers at distributed sites differs architecturally from the infrastructure SCADA was built to manage.
First, consider the communication protocol. EV chargers use OCPP (Open Charge Point Protocol), carried over WebSocket over TLS. That is a web application protocol, not an industrial protocol. Connecting OCPP chargers to SCADA therefore requires a protocol translation layer, adding complexity and a possible failure point. Modbus or OPC-UA bridges exist, but add latency and need custom configuration for each charger model.
Second, consider operations. SCADA assumes on-premise servers at sites, VPN infrastructure linking them to a central system, and an IT or OT team to maintain everything. OS patches, database backups, firewall rule updates, and certificate renewals fall to you. For an operator with 15 chargers and two operations staff, this adds substantial overhead without directly improving charging operations.
Third, consider the update cycle. SCADA software follows industrial release timelines, with a major version perhaps every 12 to 24 months. EV charging protocols and business needs move faster. OCPP 2.0.1 is already being deployed with device management profiles and certificate handling absent from OCPP 1.6. A shared SaaS platform can update every two to four weeks.
A SaaS CSMS Architecture
A cloud-hosted Charging Station Management System (CSMS) connects chargers through WebSocket over TLS directly to servers in a cloud region. Operator sites need no on-premise hardware beyond the chargers and a standard commercial internet connection.
At startup, the charger opens the connection, authenticates with its configured Charge Point Identity and password, and keeps a persistent WebSocket connection. OCPP messages including BootNotification, StatusNotification, MeterValues, StartTransaction, and StopTransaction use that connection. The CSMS routes messages, logs sessions, generates alerts, and serves the operator dashboard.
For operators, the interface is a web application opened in a browser. Status updates are near-real-time, typically within 5 to 30 seconds depending on heartbeat configuration. Dashboard commands such as remote start, remote stop, change configuration, and firmware update trigger reach the charger within seconds when connectivity is healthy.
The infrastructure model is a monthly subscription per charger, without upfront server hardware, a VPN to maintain, or OS patching. Platform updates run in the background and require no operator action.
Where SCADA Fits High-Voltage or Hybrid Sites
SCADA can suit one EV deployment profile: large utility-scale charging hubs sharing infrastructure with solar generation and grid-scale battery storage, where the site operator also handles substation-level protection coordination.
Here, charger dispatch must coordinate with inverter state, battery state of charge, and the grid import limit at substation level, all within a response window of a few seconds. A cloud round-trip for each control decision is unsuitable. On-premise SCADA or an edge controller with local control logic fits, potentially with a cloud layer for monitoring and reporting.
That profile differs from a fleet operator with three office sites and 15 AC chargers. For the latter, the choice is straightforward.
Practical Questions for Operators
When an integrator suggests SCADA for your charging network, ask three questions. Does it connect natively to OCPP, or need a protocol bridge? If bridged, request failure-mode documentation and clarify who supports it when it fails. Where does the server run, and who patches it? Finally, what is the cost per charger per month after spreading implementation over three years and adding the annual support contract?
For the Pune operator's Rs 7.8 lakh SCADA proposal, 15 chargers over three years worked out to roughly Rs 4,300 per charger per month before their own IT labor time. A SaaS CSMS for the same count costs a fraction of that, with no maintenance labor time required.
They chose SaaS and had live sessions running across all three sites in under two weeks from the decision date. Operators who have done this well choose the architecture for their operating problem. Operators who have not start with the technology category.