Energy Management can be defined as the proactive, organized and systematic management of energy use in buildings or organizations that are used to satisfy both environmental and economic requirements. We can take the illustration of power curtailment in a solar energy project that leads to the loss of clean/ green energy generation for solar project developers. It can be tackled using the proactive major taken for other generations source which can support to sudden changes for load demand.
The power curtailment involves the management of oversupply of solar energy. In my opinion, if power curtailment takes place regularly then battery storage systems can be used to store curtailed power this use to smoothen the solar of next day generation hours. This way it will help to reduce the metering curtailment so that it shall be implemented to stabilise the grid. In this case, additional battery storage, the CAPEX of the solar project will increase respectively which is again the task for the solar project developer.
In this pandemic situation, the operational solar project is continuing to supply power to the grid as it is an essential service of the power sector industry. The operational solar project and solar parks are facing issues related to lack of resource availability for preventive maintenance of solar project equipment and support from original equipment manufacturer are not extensively as earlier. Due to this unapproachability of material which leads to keeping feed the solar power with the rest of operational capacity and with available resource only.
Also, the large-scale project which is under execution majorly affected in this unavoidable situation of the pandemic, the more details of final extensions of commissioning for ongoing execution solar project may confirm at the end of Q2, after the pandemic situation under control.
In the distribution system sector smart metering expected with include the prepaid metering scheme, again it may be impacted to the pandemic situation in the country.
The development on the off-grid system seems to be growing continuously from the last few years, due to the awareness of off system and technology are increasing day by day. the grid is posing an excessive number of complex tasks on the functioning of inverters in case distributed type systems. In advanced capabilities such as voltage and frequency sensors allow smart inverters to detect grid abnormalities, communication with the control panel of diesel generator and the power can be controlled using the automatic function of the inverter. This type of smart inverters system can improve the productivity of small manufacturing industries, the import and export power can be controlled.
Inverters play a vital role in any solar energy system, inverter technology improving with adding a new feature to optimize the loss figure of inverter efficiency. The inverter manufacturer is flexible to provide the centralised and decentralised (string) inverters, so solar PV project developers and EPC player can achieve the best LCOE (lowest Levelized cost of energy). As the industry moving towards string inverters to reduce the DC cable losses which will be less in the assessment with a central inverter system. String inverter system reduces the footprint of the local transformer station of the solar project. The 3-phase string inverter will be more popular in future for the utility-scale system. Moreover, string inverters are equipped with more MPPT’s, wide range of MPPT voltage, high efficiency, continuous grid monitoring, Insulation monitoring device, Ground fault detection, additional communication options etc.
The multiple MPPT features it can be installed in the plant which have high land undulated contour, MPPT will work more efficiently and it can give optimised output power compared with one MPPT inverter. The string inverter is easy to install on utility as well as rooftop scale projects. It can be installed on the wall, module mounting structure, separated free-standing supporting structure on ground-mounted type solar installations.
Every string monitoring is an important aspect that could be monitored continuously to understand the string power availability and power curve of a string inverter. Some inverter manufacturers offer hybrid inverter and smart inverters that can be used for small scale projects like commercial complex, institution and residential area. This smart having feature control and monitoring using mobile applications, auto priority settings for battery charging, battery discharging, managing consumption of instant solar power, managing grid power import and export.
At the end of Q2 and Q3 of 2020, might solar industry would suffer a lack of supply and delay in supply for solar inverter due to pandemic which is the most significant issues. The UPS systems are used for solar PV plants that provide emergency power to a load in case of grid failure, it provides emergency power to control circuitry of switchgear, emergency power to weather monitoring system, emergency power to plant lighting etc. The UPS designed for local transformer station ranges from 3kVA to 8 kVA and main transformer station/ main control room are ranging from 8 kVA to 15 kVA which depends on block sizing/ capacity of solar projects. For solar project, industrial-grade UPS have used this application, as load demands are different than commercial and residential loads. In the general engineering practice, 4 to 6 hr battery back is necessary for local transformer station and 6 to 10 hr are necessary in case of main transformer station/ main control room of the solar project. The ups system innovations developed the compact solutions offering for the solar industry, so it is easy to install integrated with switchgear compartment to the optimized cost of extra enclosure requirement for UPS system at transformer stations. In the case of main transformer station/ main control room is constructed in cement concrete, segregated room considering the ventilation requirements for UPS and Battery are provided.
One of the issue UPS systems face are caused due to a temperature rise which is mainly due to metallic enclosure are used for installation in solar PV project. The temperature rise issue can impact the UPS output power and life of the UPS system, proper ventilation is required to maintain the metallic enclosure airflow.
About the Author:
Sandip Paithankar is a solar PV design & engineering professional at Engie Solar, an in-bound design and engineering platform that helps companies in the development of solar projects. Previously, Sandip worked as a PV design engineer for a KACST KSA. He post-graduated with honours from MIT Pune with a degree in Energy Management and graduated with honours from Pune University with a degree in Electrical Engineering