10 key point of DERC proposal on net metering & connectivity in respect of rooftop solar PV projects
Considering availability of around 300 sunny days, reasonably good available rooftop area which can complement the solar PV system DERC has issued the proposal on net metering and LT connectivity. DERC is not the first government body to propose/ launch the net metering policy at state/ UT level. Tamil Nadu, Uttarakhand, Andhra Pradesh, and Punjab states have already come up with net metering arrangement to promote the rooftop solar PV market. This article is going to highlight the 10 key considerations of the Delhi net metering and connectivity proposal.
- Net metering means consume solar PV electricity at priority and in case; there is surplus electricity that will be fed back into the grid. If solar Power is not enough to meet the total load of the building then grid electricity will be available. However, DERC has adopted international context and district the rooftop ownership in two parts
- Self-owned arrangement wherein rooftop owner also owns the PV system.
- Third party ownership in which a developer owns the PV system and also enters into a lease/commercial arrangement with the rooftop owner.
Self ownership means, the rooftop owner, who is also the electricity consumer for the utility, own the rooftop solar system. Third party ownership means, owner of the rooftop will provide rooftop to a solar PV installer and either pay for the electricity/ lease rental of monthly basis. in case of DERC proposal, a third party owned system, would result in an open access transaction with implications of wheeling charges and surcharge relating.
- For any rooftop system with net metering arrangement connectivity of the solar PV in the existing system is always a crucial point. As proposed by the DERC, there will be two meters (Main meter- Bidirectional and check meter) to measure the import and export. First meter has to be connected at the generator end after inverter. The point of solar power injection may be in between the load and the Import/Export (Bi- directional) meter. Second meter will replace the existing meter in the consumer’s premises. Installation of check meter is optional for the capacity less than 20kW. The cost of these meters shall be borne by the consumer
- For the proposal modals and the general market trend, typical solar rooftop capacity is in accordance with the building sectioned load or less than that. However, in the DERC proposal, DERC has allowed the higher capacity than the sanctioned load, however, in this case consumer needs to pay SLD charges. Above all, maximum cap of the installation capacity is 1 MW for a single net metering point.
- There is a large possibility that rooftop installations capacity goes high. Further, due to this there can be higher flow of reverse electricity to the grid. This may impact the present grid infrastructure and safety. Hence, considering this fact, DERC shall provide net metering arrangement to all eligible consumers as long as the cumulative capacity to be allowed for a particular distribution transformer shall not exceed 15% of the capacity of the distribution transformer. The latter category of consumers can be given the benefit of deemed RPO self-consumption of electricity by consumers who are not defined as obligated entities under the RPO framework.
- Rooftop SPV generation is capped @ 90% of the consumer consumption in a year. The carry forward of excess energy generation will be allowed from one billing cycle to the next billing cycle up-till the end of the same financial year only. Any excess generation (above 90 per cent) at the end of the financial year would be considered as free energy and not offset against the consumer’s consumption.
- The consumer shall receive a net import/export bill indicating either net export to the Grid or net import from the Grid. If electricity consumption is higher than the SPV generation, then net import will be raised by the distribution licensee after taking account any carry forward amount. If it is a net export bill, then credit amount shall be carried forward to next month for adjustment against next month’s import bill.
- Net credit available in account of the consumer will be finally adjusted in April of the next year, subject to the cap @ 90% of the total consumption.
- Connectivity: DERC has proposed different connectivity voltages for the different solar PV capacity installation.
- For capacity upto 10 kW connection can be made at 240 V or 415 V
- For 10 kW to upto 100 kW connection can be made at only 415 V-three phase
- For capacity above 100 kW connection should be made at HT of EHT line.
- O&M: The responsibility of operation and maintenance of the solar photo voltaic (SPV) generator including all accessories and apparatus lies with the consumer. System equipment should be in line with the MNRE/ CEA standards. System protection should be taken on priority while installation and for the operation of the system. The consumer shall comply with DERC/DISCOM/CEA requirements with respect to safe, secure and reliable function of the SPV plant and the grid.
- RPO and REC: Net-metering injection is not eligible for REC. The quantum of electricity consumed by an eligible consumer, who is not defined as an obligated entity from the rooftop solar system under net-metering arrangement shall qualify as deemed Renewable Purchase Obligation (RPO) for the distribution licensee.Posted by: Gaurav Sharma download document: http://www.derc.gov.in/Public%20Notice/Net%20Metering/DERC%20Net%20Metering%20Proposal.pdf