India is moving to keep rooftop solar telemetry on India-based servers to protect data leakage, as the Ministry of New and Renewable Energy (MNRE) advances a national, vendor-neutral data layer for inverters under the PM Surya Ghar program, which targets 10 million homes and 30 GW of capacity.

The draft framework standardizes how inverter-side devices authenticate and publish data to a centralized platform, aiming to mitigate cyber risk and enhance grid visibility.

The push is framed around energy sovereignty, amid concerns that some monitoring dongles and loggers have been routing data to overseas servers. The draft establishes a secure, authenticated data path, ensuring utilities maintain consistent visibility without compromising critical infrastructure.

Earlier this year, reports surfaced that the U.S. had discovered ‘rogue’ communication devices not listed in the product literature of China-made inverters, thereby raising cybersecurity risks.

Integration Testing

Under the draft Remote Monitoring System RMS guidelines, each site uses a machine-to-machine (M2M) SIM-based communication unit, such as a modem, dongle, or data logger, placed beside the inverter. The device identifies itself using digital client certificates and International Mobile Equipment Identity (IMEI) numbers, connects over encrypted channels, and publishes data using the Message Queuing Telemetry Transport (MQTT) protocol, as specified in IEC 20922.

Field equipment is polled over Modbus and Device Language Messaging Specification (DLMS). Messages include reserved headers such as IMEI, timestamps, storage index values, and rotating one-time password (OTP) fields. Store-and-forward buffering ensures that data collected during outages is uploaded when connectivity returns. Because inverters maintain lifetime counters, daily generation can be reconstructed even if packets are missed.

According to Servotech Renewable Power Systems, MNRE has begun integration testing on September 1, 2025, with original equipment manufacturers (OEMs) connecting devices to a centralized national software platform over M2M SIM links.

Sarika Bhatia, Director at Servotech, said her company is aligning with the vendor-neutral open protocol to integrate with the national platform.

Another inverter manufacturer said MNRE is not seeking continuous streaming to the national platform at this stage. “For MNRE’s purposes, they don’t want continuous streaming — one daily submission of generation data, along with historical aggregates, is sufficient,” the company said, while distinguishing this from PM KUSUM, under which devices send live data every 10 minutes over MQTT.

Bharat Singh, Director – Sales & Marketing at Deye New Energy, noted that at present, there is no start date or mandate date for the integrated program. “Deye at present has a huge stock of inverters in India as per the forecast of the PM Surya Ghar program. A six-month prior intimation or a 6-month relaxation time should be provided for liquidating the stocks of inverters in India,” he said. He also stated that Deye will start to provide inverters matching these rules at the earliest from January 2026 onwards.

India-based Servers

Both manufacturers stated that the MNRE has set two clear expectations: data should be stored on servers in India, and it should be fed into a centralized dashboard, although the final design of that dashboard is yet to be decided.

The inverter manufacturer said BSNL is among the options under consideration for hosting. He also said MNRE is insisting on M2M SIMs for communication but has not mandated a particular operator.

“Many OEMs are approaching us for low-cost SIMs and monitoring devices to meet this requirement. We’ve already developed a low-cost monitoring unit to address this demand,” the second manufacturer said.

The manufacturer noted industry portals could help accelerate the rollout: “We’ve proposed that MNRE could leverage the portals that OEMs already operate, since every inverter company has dashboards, but their requirements are more specific.”

Separate, Removable Loggers Favored

Both manufacturers said the communications unit will typically be separate from the inverter. Heat and voltage fluctuations inside inverters were cited as technical reasons, while warranties and customer choice were cited as commercial considerations. “For string inverters, it’s almost always a separate unit, while microinverters often use wireless protocols like Zigbee or Wi-Fi to connect to a gateway device,” the manufacturer said.

Most systems support RS-485 internally, with external connectors such as USB, RJ45, and M16 seen in the market. Some OEMs use proprietary protocols that tie devices to their own loggers. “Either way, data is always encrypted, and there’s a handshake between the inverter, the monitoring device, and the OEM’s server. You can’t simply plug in and start reading or controlling the inverter without authentication,” the manufacturer added.

Singh noted that while both built-in and removable SIM-based dongles are available, the best solution is a removable SIM-based dongle, as it allows consumers to choose the service provider of the SIM for their usage in the inverter. The consumer will spend extra money on a dongle (SIM-based) because built-in Wi-Fi inverters are less expensive compared to a removable SIM-based solution.

Deye is also developing a two-path system in its IoT-based system. The first path will be for recording and storing data in the government portal, and the second path will be for accessing the brand app, vice versa. This also applies to the brand updating the firmware for better operation of the inverter.

Grid Stability, Visibility, and Buffered Telemetry

The draft guidelines frame the effort around secure data paths and standardized control. The manufacturer linked the data initiative to grid performance. “MNRE’s push is less about hardware redesign and more about data sanctity and grid stability. Today, many inverters don’t follow reactive power standards, creating voltage fluctuations that destabilize the grid.” The company said standardizing even one daily data packet per inverter would create visibility “without overburdening connectivity.”

Manufacturers say loggers incorporate store-and-forward mechanisms with onboard memory and backup power, allowing data collected during outages to be uploaded once connectivity is restored. Because inverters store lifetime counters, they said daily generation can be reconstructed even if some packets are missed.

What End Users See and How Often

Manufacturers said consumer-facing telemetry will continue on brand apps. “For homeowners, we emphasize showing energy generated every 10 minutes, since momentary power readings can be misleading,” the manufacturer said. “B2B customers, on the other hand, get both power and energy data for operational monitoring.”

Servotech said it expects the PM Surya Ghar portal to remain focused on program monitoring and compliance rather than becoming a comprehensive consumer dashboard.

The second manufacturer said, “nothing is formally documented” on timelines and described the process as “premature,” noting that expectations of four to five months have been discussed informally.

SIM Supply and Cost

Servotech said DISCOMs would manage data plans in many states while OEMs supply M2M-enabled loggers. Its inverters already ship with remote-monitoring dongles. Customers typically will not have to arrange SIMs themselves, though practices may vary by state. The second manufacturer stated that some models allow end-users to insert their own SIM cards and recharge data packs. Both pointed to small payloads and low recurring costs.

Manufacturers expect a modest increase in the price of compliant setups. The second manufacturer compared Wi–Fi–based residential loggers imported from China, priced at ₹600 (~$7) to ₹700 (~$8), with India-compliant SIM loggers at around ₹2,000 (~$23). The company estimated ₹2,000 (~$23) –₹4,000 (~$45) per site when a single communication device serves multiple inverters at an installation.

“The real bottleneck won’t be cost but availability. If MNRE mandates retrofits at scale, there will be a sudden demand spike that no manufacturer can immediately meet,” the company said, adding that regulation is more likely to apply to new installations going forward.

Servotech stated that its first program-compliant units are in the integration phase, with production readiness and nationwide distribution to follow after final protocol confirmation and successful alignment with the national platform.

Singh noted that installers or homeowners will have to spend anywhere between ₹1,000 (~$11)- ₹2,000 (~$23) per year on the cost of the SIM provider, along with a one-time cost of ₹2,000 (~$23) – ₹3,000 (~$34) for a dongle.

Singh also noted that there will be a delay in the supply of the new version of inverters to markets by distributors and trading companies, as they must first liquidate their stock of older versions of inverters. Therefore, the government must allow a relaxation period before announcing the deadline for starting to use compliant dongle/logger-based inverters.

Manufacturers widely anticipate a six-to-eight-month supply shortfall, given the increased demand for M2M-enabled loggers.

Models and Warranty Links

Manufacturers said the market is coalescing around two approaches: bundling approved loggers with inverters or creating an enlisted marketplace of MNRE-compliant monitoring devices from third parties, including white-label partnerships. “Our own logger, while more expensive than Chinese imports, is already compliant and ready to integrate,” the second manufacturer said.

The company also said warranties are increasingly tied to data communication, as diagnosing failures in sealed inverters requires telemetry. “Simply put, without communication, you’re blind.”

Singh noted that while the warranty won’t depend on the inverter connected to the national platform, warranty or service issues can be resolved only when it is accessible to brands to update the firmware, as 80% of issues are solved remotely by firmware updates.