Frequently Asked Questions

A Grid Interactive Rooftop PV system comprises of electrical and electronic equipment such as solar modules, inverters, cables, switch gears, etc. When these components are connected and placed on the roof of buildings exposed to sunlight, the system starts generating electricity. A GRPV system generates electricity that can either be injected directly into the distribution grid or used for captive consumption at installation premises.

Grid Interactive Rooftop Photovoltaic systems are of two types:

  • Systems without battery storage.
  • Systems with battery storage.
  • Cheaper and environment friendly electricity.
  • Excess energy can be fed into the grid with tariff as determined by the State Electricity Regulatory Commissions.
  • Electricity generation occurs at consumption center thus, saving transmission and distribution losses.
  • Lower payback period.
  • Requires minimal maintenance.
  • 25 years guaranteed lifespan of the solar photovoltaic panels.
  • Subsidy is available from MNRE.
  • Highly modular.
  • Quick installation.

No, Grid Interactive Rooftop Photovoltaic systems cannot generate electricity at night. In case of absence of generation by the system, power supply can be availed from the electric grid. Battery can be used to store energy for later use, i.e, night or monsoon.

Under net metering, electricity generated by the Grid Interactive Rooftop Photovoltaic system is first utilized by the consumer to meet their internal/captive requirements and excess electricity, if any, is exported to the grid. Subsequently, when the consumer imports power from the grid, the exports are adjusted against the imports, lowering electricity bill.

Net meter (bi-directional meter) usually records the energy imported from the grid to meet the load and surplus energy exported to the grid after consumption. Both energy import and export are recorded in the net meter. The difference between import and export readings is the actual energy consumed/delivered.

For each kWp, the Grid Interactive Rooftop Photovoltaic system installed on a south-facing roof will generate four to six units of electricity per day. However, depending upon the weather conditions, the energy generation reduces by around 20 percent for east or west facing roof.

A Grid Interactive Rooftop Photovoltaic system is made up of different components. These include PV modules (groups of PV cells), grid tied inverters, circuit breakers, relays, energy meters (net/gross), module mounting structures (MMS), cables, etc.

Solar Projects of capacity up to 500 kWp at one premise based on the technologies approved by MNRE are eligible for connecting the project with the Grid under these Regulations. The capacity of the Solar Project to be installed under Group Net Metering or Virtual Net Metering framework shall not be less than 5 kWp and more than 500 kWp.

Provided that the Solar Project of rating higher than 500 kWp can be considered by the Distribution Licensee if the distribution system remains stable with higher rating Solar Project getting connected to the grid.

The Eligible Consumer may install the Solar Project under the ‘Joint Electricity Regulatory Commission for the State of Goa and Union Territories (Solar PV Grid Interactive System based on Net Metering) Regulations, 2019’, provided the Solar Project is:

  • Within the permissible rated capacity as defined under these Regulations;
  • Located at the Consumer’s Premises;
  • Interconnected and operated safely in parallel with the Distribution Licensee’s network.

Consumers will generate solar power for self-consumption and are allowed to feed the excess solar power into the grid, which shall be adjusted under Net Metering as per provisions of these Regulations.

The maximum Solar Power Generation capacity to be installed at any Eligible Consumer’s Premises shall not exceed his Contract Demand (in kVA) or Sanctioned Load (in kW).

Most roofs are strong enough for solar installation without any reinforcement. However, in case of larger systems, it is suggested to consult a qualified Structural Engineer.

Currently, the following business models are in vogue namely, self-owned (capital expenditure [Capex] model), Renewable Energy Service Company (RESCO) model and third-party owned model. “RESCO” means an energy service company which provides renewable energy to the consumers in the form of electricity.

Capex Model: Consumers develop solar rooftop plant within their premises to own, operate and generate electricity for self-consumption and sell excess electricity to the utility (under net metering) or sell entire electricity to the utility (under gross metering). Generally, self-owned business model is preferred for its simplicity. However, this model also has disadvantages such as high capital cost for the consumer and high technology and performance risk.

RESCO Model: A RESCO builds, owns and operates GRPV plant in the premises of a consumer to generate and sell electricity to the consumer. Consumer may further engage in net metering or gross metering arrangement with DISCOM.

In RESCO, consumer does not invest in the GRPV power plant; instead, a RESCO developer invests and sets up the system. RESCOs are specialized solar developers; they can handle technology and operation risks in a better way. However, RESCO model faces several challenges such as power off-take risks, contractual risks, etc.

Third Party Model: A Rooftop or Land Owner may lease out / rent the Rooftop Space/ Land to a Solar Project Developer on a mutual commercial arrangement. Under this arrangement, the owner of the roof / land engages a turnkey installer to design and install the project. The Commercial arrangement between the project developer and the Roof / Landowner will be submitted to the Buyer of the Solar Power / Distribution Licensee for the records.

Suitability of these models depend on one’s ability to meet the costs.

Yes. All applications related to Grid Interactive Rooftop Photovoltaic shall be processed through UWP for Solar Net Metering Chandigarh. Upon submission of DISCOM Application for Interconnection, Chandigarh Electricity Department, will check the technical feasibility and provide a response through the UWP for Solar Net Metering Chandigarh. Applicants can register themselves through UWP for Solar Net Metering Chandigarh and apply online directly using relevant forms and formats to the approving authority.

Eligible Consumers are consumer of electricity in the area of supply of the Distribution Licensee, who uses a self-owned or third party owned solar power project, to offset part or all of the consumer's own electricity requirements.

A maximum of 500 kWp at a single location is allowed under net metering. Solar Project of rating higher than 500 kWp can be considered by the Distribution Licensee if the distribution system remains stable with higher rating Solar Project getting connected to the grid

No. Bi-directional and Solar Energy meters (unidirectional meter) shall be required by consumers to avail net metering facility. Check meters are required for installed GRPV capacity of more than 20 kW. Check Meters shall be mandatory for Solar Project having capacity more than 20 kW. For installations having capacity less than or equal to 20 kW, the Check Meters would be optional: Provided that the cost of Check Meter shall be borne by the Consumer, and such meter shall be tested and installed by the Distribution Licensee.

Please refer the Joint Electricity Regulatory Commission for the State of Goa and Union Territories (Solar PV Grid Interactive System based on Net Metering) Regulations, 2019’.

The Project Developers shall adhere to the National & International Standards specified by MNRE & CEA’s Technical Standards for Connectivity of Distributed Generation Resources - Regulation 2013.

Yes, some banks provide loans especially for solar rooftop systems. This information is available on the UWP for Solar Net Metering Chandigarh.