Tech Advantage: BRPL’s experience with smart grid applications

BRPL’s experience with smart grid applications

BSES Rajdhani Power Limited (BRPL) is one of the few technologically advanced distribution utilities in the country. The discom, which is a joint venture of Reliance Infrastructure Limited and the Delhi government, has successfully reduced its aggregate technical and commercial (AT&C) losses from 51.5 per cent during 2002-03 to 8.06 per cent during 2018-19. It has achieved key milestones by providing enhanced consumer services as well as strengthening its power distribution network. This has been made possible through the use of technology.

BRPL has successfully deployed smart grid technologies such as smart metering as well as load management and outage management systems to build a better power distribution network. Going forward, the discom will invest in a host of next-generation technologies such as blockchain, solar power and battery storage that are expected to transform the grid in the coming years.

Journey so far

The company’s customer base grew by 3.23 per cent, from 2.47 million during 2017-18 to 2.55 million during 2018-19. During 2018-19, the company recorded a peak demand of 3,216 MW and a turnover of Rs 900 billion. AT&C losses stood at 9.42 per cent and 8.06 per cent during 2017-18 and 2018-19 respectively.

The key objectives of BRPL’s smart grid strategy were technical loss reduction, providing enhanced services to special consumer categories (such as tenants, and high-end consumers) and outage management.

The utility has been continuously downloading consumers’ meter data since 2006 using hand-held units. The utility’s meter data downloading efficiency stands at 99.5 per cent, including for single-phase meters. For electricity theft control, the utility has deployed pole-mounted meters and since its AT&C losses are already low (at 8.06 per cent) there is not much scope for a reduction in commercial losses.

BRPL’s special consumers include tenants/customers with temporary connections and prepaid customers. The utility adopted smart metering for these consumers to overcome a number of issues. For instance, customers with temporary connections often tend to overdraw electricity beyond the stipulated time; and in the case of tenants, rents remain unpaid for long durations and hence pile up. BRPL has started giving temporary connections through smart meters within 24 hours of application. All government consumers have prepaid meters installed on their premises. In high-theft areas too, pole-mounted general packet radio service (GPRS)-based smart group meters have been installed.

In order to reduce technical losses, BRPL is carrying out online monitoring of grid transformers and 11 kV feeders. For balancing the load, data is continuously monitored to identify overloaded and underloaded assets, and the load is transferred accordingly. Frequent voltage drops in the power system indicate high technical losses in the distribution network. To counter this, BRPL has installed an application to monitor grid stability. As a result of these measures, BRPL’s technical losses reduced by 0.8 per cent during 2018-19 as compared to those during 2017-18. The utility is now targeting to further reduce its technical losses by 0.6 per cent with minimal capex.

BRPL has adopted various smart technologies for outage management such as digitalisation of ring main units (RMUs), automated meter reading, distribution transformer (DT) health monitoring and low tension (LT) feeder monitoring. The RMUs transmit data to the discom through fault passage indicators (FPIs) and circuit breaker monitors. Also, fault tracing is being carried out through relay reading.

Further, 4G- and 2G-based AMRs are being used for DT monitoring and field force application has been deployed for digital tracking of work. Real-time condition-based monitoring of DTs and load monitoring of critical LT feeders/ aerial bunched cables is also being carried out through sensors.

DT health monitoring has aided BRPL in taking informed decisions regarding the operations and maintenance of transformers based on data sent by sensors. DT health monitoring is a perfect example of IT and OT convergence where OT (sensors) helps in delivering accurate asset performance information and IT converts the data into meaningful insights and actions. As per the data from the DT health monitoring system, overvoltage and outage constituted 39 per cent and 22 per cent of the alerts, respectively, sent to the utility, followed by load reduction (15 per cent), lug temperature (15 per cent), oil temperature (5 per cent), overload (2 per cent), oil level (1 per cent) and undervoltage (1 per cent).

In addition, the company has taken initiatives such as the configuration of intelligent electronic devices at 11 kV panels in extra high voltage grids, FPI installation on RMUs, online monitoring of first switching stations, the installation of single way breakers, and the implementation of the distribution management system for quick restoration of power supply in case of outages. Power reliability is being ensured by monitoring the feeder power factor and maintaining phase balance for optimum loading even during peak hours.

Overall, these solutions have significantly helped BRPL in reducing outages. The total outage duration has reduced by 44 per cent in 119 high-breakdown feeders. The typical outage handling time has also gone down from 60-90 minutes to 17-25 minutes in 86 per cent of the cases. Also, data from the GPRS and the geographic information system (GIS) have helped the utility to plan the location of batteries and solar PV systems.

 Future plans

Smart metering is a good technology which monitors electricity pilferage and power losses. BRPL plans to aggressively pursue emerging technologies. It is actively promoting rooftop solar PV installations in its licence area. In January 2018, it partnered with GIZ and The Energy and Resources Institute (TERI) to launch the Solar City Initiative, with the purpose of setting up grid-connected rooftop solar projects to manage peak demand in Delhi. In Phase I, Dwarka was selected for the installation of such projects and around 100 housing societies and apartment complexes signed up for the installation of rooftop solar systems. Phase II, which was launched in end 2018, covers Shakur basti.

The discom recently partnered with Power Ledger, a blockchain-based technology start-up in Australia, to launch trials for a peer-to-peer (P2P) energy trading platform in Delhi. BRPL has thus become India’s first discom to use a blockchain-based platform for P2P solar trading. The trial initially comprised 5-6 MW of existing solar infrastructure, servicing a group of gated communities in Dwarka. During the trial, residents with rooftop solar infrastructure sold excess solar energy to their neighbours instead of letting it spill back into the grid. This provided participants access to cheaper renewable energy and prosumers (those that own solar power infrastructure) an opportunity to monetise their investments in solar assets. BRPL was able to access a cost-effective energy alternative during times of peak demand, leading to increased efficiency and power supply reliability. BRPL and Power Ledger plan to expand the scope of trials by including blockchain-enabled solutions for group net metering, virtual net metering, electric vehicle (EV) charging and virtual power plant applications in the near future. Meanwhile, the discom is taking steps to set up charging stations in line with the government’s e-mobility vision. It plans to set up over 150 charging stations across its licensed area, in partnership with other entities. Of this, around 50 smart EV charging stations will be set up during 2019-20. Blue Smart Charge, the first of the smart public EV charging stations, was inaugurated in June 2019. It can charge two EVs simultaneously.

BRPL is part of the UI-ASSIST (US-India collaborative for smart diStribution System with Storage) initiative; under this, the discom will carry out three pilots by installing a 330 kWh battery energy storage system. As part of the initiative, in December 2019, TERI invited bids for battery storage on a turnkey basis.

Clearly, BRPL’s efforts are strengthening its position as a prominent technology leader in the power industry.