2021/112 Supported by K NKONW A A WELDEGDEG E OL N ONTOET E S ESREI R E ISE S F OFRO R P R&A C T HTEH E NEENREGRYG Y ETX ITCREA C T I V E S G L O B A L P R A C T I C E THE BOTTOM LINE Installing Solar Power Plants in Snowbound Areas: Solar power plants can enable a shift away from polluting Lessons from Himachal Pradesh, India alternatives such as diesel-based generation, especially in isolated, Why should we consider solar photovoltaic (PV) (Bisht 2020). The state power distribution company has a distribution feeder network in the valley, but the relative distances, lack of supply snowbound areas where the projects in snowbound areas? opportunity cost of land is relatively (due to the breakdown of a mini hydropower project near Kaza), and Solar PV installations can provide clean and the possibility of power shutdowns in winter make it necessary for low. Technical solutions to the affordable energy in snowbound areas, along with many commercial establishments to use high-speed diesel genera- challenges of difficult terrain and employment for local residents tors as their main power source. climatic conditions include bifacial Installing solar power plants in snowbound areas offers an modules and so-called passivated Transitioning from polluting fossil-fuel generation to solar power important avenue for reducing pollution and mitigating climate emitter and rear cell technology— is the need of the hour. But where the opportunity cost of land is change. Moreover, since most solar panels are mounted on barren high, countries must look for solutions that do not occupy valuable land or on rooftops, their installation does not involve significant all with fixed mounting systems. land. In India, for example, the government is looking at rough environmental impacts from the breaking of land or slopes It is important to train staff and terrain, including snowbound areas, as sites for solar installations. (Government of Himachal Pradesh 2016). Investments in such to optimize equipment for site- Isolated, snowbound areas may offer good options to harvest solar locations bring job opportunities and boost incomes for locals who specific risks like heavy snow resources—both at the utility scale for export and at a smaller scale may otherwise need to seek employment in faraway cities. loads. Both utility-scale projects for supply to local communities. Not only do they offer a relatively for export, as well as small setups lower opportunity cost of land; they also often have higher rates of solar irradiation. Surbhi Goyal is a Georg Goldes is a for supplying local communities, The Indian government aims to generate 40 percent of the senior energy specialist senior expert at Evergy may be explored. This Live at the World Bank. Engineering GmbH. country’s electric power from nonfossil fuels by 2030. To this end, it Wire recommends practices for plans to install 175 gigawatts (GW) of renewable generation by 2022, setting up solar installations in of which 100 GW will be solar. All states have joined hands to achieve Satyaki Bhattacharya snowbound terrain, based on the their joint renewable energy purchase obligations, aiming thereby to is a renewable energy Saurabh Nirgudkar Bank’s assessment of technical improve both their energy mix and their energy security. Himachal consultant at the World is a project engineer Pradesh, a hilly state in the north, plans to install about 1 GW in the Bank. requirements for setting up a 1 at Evergy Engineering Spiti Valley in the Lahaul and Spiti district. This area typically sees GmbH. GW solar power project in Spiti more than 300 clear and sunny days in a year but is difficult to Shraddha Suresh is an Valley, Himachal Pradesh (Evergy access and remains snowbound for up to four months of the year. energy consultant at the Engineering GmbH 2020). Tribal farmers in the remote Spiti Valley have come to rely on World Bank. expensive diesel fuel to supplement an erratic electricity supply 2 I n st a lli n g S o l a r P o we r P l a n ts i n S n o wb o u n d A r e a s : L ess o n s f r o m H i m a c h a l P r a d esh , I n d i a All in all, the extra costs needed to deal with the challenges of land surface suitable for an installation (Government of Himachal operating in snowbound areas are moderate and will likely be more Pradesh 2016). While the clear skies and low temperatures in snow- than offset by the lower cost of land. Also, the additional generation bound, hilly regions may be conducive to solar PV, the remoteness of from the solar PV plant can be used to offset any other extra costs these locations can pose logistical challenges such as long transport incurred during the construction phase and the higher cost of times and a lack of local technical support infrastructure. Proximity to Installing solar power logistics and manpower management in remote, snowbound areas. the nearest transmission evacuation facilities also plays an important plants in snowbound areas role in deciding the economics of a proposed project. offers an important avenue What challenges do snowbound solar projects pose— However, these challenges can be overcome through a careful planning and design process informed by best-practice experiences. for reducing pollution and what solutions are available? With respect to panels, bifacial modules and passivated emitter and and mitigating climate Heavy snowfall and the steep, uneven terrain of rear cell (PERC) technology provide relatively high energy yields. For change. Investments in remote project sites need to be carefully considered mounting, a twin post support system is recommended for areas during planning and implementation with heavy snow loads. Technical specifications are discussed below such locations also bring and summarized in table 1. job opportunities and Solar PV projects in snowbound areas run the risk of damage Solar panels. Crystalline silicon PV modules consist of con- boost incomes for locals from heavy snow loads and even from disasters such as earthquakes nected PV cells encapsulated in one of two ways. So-called monofa- and avalanches. While light snowfall can slide off easily without cial modules are held between a transparent front (usually glass) and who may otherwise need damaging the panels, heavy snowfall can create problems by placing an opaque substrate; whereas bifacial modules have a transparent to seek employment in stress on the support structure of the PV system (Gay 2017). front and back. Bifacial modules expose both the front and the back faraway cities. Topography poses another challenge. In mountainous terrain with side of solar cells and produce solar power from both sides of the few flat areas, it can be difficult to find a large enough contiguous panel. Crystalline silicon technology may be of the monocrystalline Table 1. Minimum technical specifications for solar projects in snowy areas Item Recommendation Remarks Solar modules Bifacial modules and PERC technology preferred. Maximizes efficiency and long life at lower up-front cost. Solar inverters String inverters. Modular, low-weight, easy to replace, lower lead time. Mounting structures Horizontal single axis trackers can be used to maximize Incur marginal extra capital expenditure up front, but this is justified by generation from the sites. In case fixed-tilt structures 5–7 percent extra generation. are used, additional back rails should be provided to mitigate snow loading. Structure foundations Using gravity weights instead of deep drilling. For fragile snowbound soil strata, soft glacial moraine type soil might be encountered randomly, so a concrete ballast type foundation is preferred. Transformers Cast resin dry-type transformers preferred. Heatable Oil-cooled transformers have oil-leakage risk and are extremely hazardous transformer banks may be used depending on in fragile snowbound areas. availability and cost. Supervisory control Site-level SCADA and one central SCADA are preferred. Very detailed input/output parameters settings and an automated control and data acquisition and operations system is preferred. (SCADA) Ratio of direct current Less than 1. Because of the electrical thresholds of inverters and transformers to alternating current operating in extreme low temperature in winters, a higher margin of safety has been considered. 3 I n st a lli n g S o l a r P o we r P l a n ts i n S n o wb o u n d A r e a s : L ess o n s f r o m H i m a c h a l P r a d esh , I n d i a efficiencies than do standard solar cells. While there are more steps in the manufacturing process, the gain in efficiency enables cost reduction at the system level. This cell architecture is the mainstream option for producing high-efficiency solar panels at competitive prices. While the clear skies Half-cut cells provide several benefits over traditional solar cells, and low temperatures in such as improved performance (slightly increased panel efficiencies), and improved physical durability owing to their smaller size and snowbound, hilly regions increased resistance to cracking. may be conducive to solar The higher average purchase cost of bifacial modules and PV, the remoteness of PERC technology is justified by their higher energy yield. Bifacial these locations can pose technology is particularly well suited to snowbound areas because of the excellent reflectivity provided by snow. Performance analysis logistical challenges such conducted for a site in Spiti Valley indicated that bifacial technology as long transport times and would provide the highest energy yield when deployed with horizon- a lack of local technical tal single-axis trackers (HSATs) and would outperform monofacial support infrastructure. technologies when deployed with HSATs or with fixed-tilt mounting systems. The risk of component failure in bifacial PV modules is not higher than for any other PV project, since they are manufactured in a manner that is similar to conventional monofacial modules. Bifacial and monofacial PERC technology is widely accepted across markets. Mounting structures. PV modules are installed on either fixed Photo: Stutterstock or “tracking” mounting structures. The structures keep the modules oriented in the right direction with a tilt that is optimized for maxi- type, in which wafers are sliced from a large single crystal ingot in mum irradiation and to provide the required structural support. Fixed a relatively expensive process, or the relatively cheaper but slightly mounting systems are straightforward to set up: rows of modules less efficient polycrystalline type, with wafers may be made by a are kept at a fixed-tilt angle. By contrast, tracking systems follow the variety of techniques, allowing them to be much larger than the sun’s trajectory, resulting in higher irradiation on the collector plane monocrystalline type. Given the logistical constraints, long-term oper- and higher energy production. ation and maintenance needs, and the challenges at the installation Tracking systems generally provide the highest energy yield, stage, monocrystalline PV module technology is recommended for followed by manual seasonal tilt systems, fixed-tilt systems facing snowbound areas. south, and, finally, fixed-tilt systems in the east-west orientation Different cell architectures, module processing technologies, (which require less space than south-facing systems). Tracking and product solutions have been introduced in the market in recent systems and seasonal tilt systems require 1.5–2 times more land years to boost the output of crystalline PV modules and bring down to avoid shading as compared with a fixed-tilt system of the same costs. These include PERC technology, half-cut cells, and bifacial nominal capacity. modules. For sites in mountainous regions, the installation of trackers is PERC technology improves light capture near the rear surface difficult because only limited inclinations are manageable and then of a cell and optimizes electron capture. The main advantage of only with additional costs (for flexible joints between each table). this cell structure is that it enables manufacturers to achieve higher Trackers can be installed on sites with a maximum north-south slope 4 I n st a lli n g S o l a r P o we r P l a n ts i n S n o wb o u n d A r e a s : L ess o n s f r o m H i m a c h a l P r a d esh , I n d i a of up to 17°. Additionally, trackers require frequent inspection and • On-site concrete piling. This option is the most suitable for all maintenance owing to their motorized and moving parts, with elec- systems, as the pilings are customized for a given soil stratum trical components generally needing replacement every five years. and terrain while having a strong tolerance for uneven and Manual seasonal trackers are complex in design and implementation, sloping terrain. On-site concrete pilings do not require specialist especially in harsh climatic conditions. skills to install. Fixed-tilt systems have Fixed tilt systems, on the other hand, have no moving parts and no moving parts and require no maintenance. The up-front capital cost is lower, and dam- What sorts of design specifications are called for? age to modules caused by the mounting structure can be avoided. require no maintenance. A detailed baseline study will go a long way in Ground-mounted structures may be supported by a single post The up-front capital cost (mono-pile) or a twin post (dual-pile) support system. A twin post, ensuring a robust solar project under harsh is lower, and damage to although more costly, is recommended for sites subject to strong conditions modules caused by the winds in the north-south direction and high snow loads. Alternatively, Electrical engineering. It is extremely important that the site’s custom-designed structures may be used to solve specific engineer- mounting structure can be average temperature be reflected in the electrical design of the ing challenges or to reduce costs. These also offer a way to use local avoided. The lower energy power plant to avoid damaging and overloading the components, suppliers or fabricators to fulfill local content obligations. The key is yield of a fixed-tilt system as solar cells such as semiconductors are sensitive to temperature. to design a system that is simple and repetitive to install, as labor The most affected parameter is the panel’s open-circuit voltage. This can be partly balanced out costs can be a significant element of installation. The lower energy goes down with an increase in temperature, resulting in reduced yield of a fixed-tilt system can be partly balanced out by increasing by increasing the installed power output—and vice versa. Thus, the temperature influences the the installed peak capacity of the modules. peak capacity of the selected ratio of direct current (DC) to alternating current (AC). For Ground-mounted PV systems also require appropriate foun- modules. instance, for projects in Spiti Valley, where the average temperature is dations for the mounting structure (which will affect the choice of about –4.4oC, DC/AC ratios between 0.9 and 0.95 are recommended support system). The most favorable option needs to be determined so as not to exceed maximum limit values for electrical thresholds. specifically for each proposed site, based on a ground survey. (The exact ratio depends on the technical specification of the Options available for snowbound areas include: inverter.) This is in line with high-altitude projects all over the world. • Driven piles. A beam or pile is driven into the ground. This is To protect against environmental influences such as ultraviolet a low-cost solution that can be quickly implemented. Specialist (UV) light, rain, and snow, the DC and AC cabling should be installed skills and pile driving machinery are required, and predrilling may inside the mounting structure and under the PV modules. Cables be necessary in rocky terrain. exposed to sunlight are best protected with additional plastic pipes to • Earth screws. Helical earth screws, typically made of steel, mitigate the risk of their outer shield breaking and to avoid isolation are economical for large-scale installations and are tolerant of problems in the PV power plant. Armored cables are recommended uneven or sloping terrain. These require specialist skills and in trenches where no sand is available. (Normally, cables need to machinery to install. Predrilling may be necessary in rocky be embedded in a layer of sand approximately 20–30 centimeters ground. thick to protect them from damage and to avoid outages due to low • Precast concrete ballasts. This is suitable where the ground isolation resistance.) Where it is difficult to dig deep trenches due to is difficult to penetrate due to rocky outcroppings or subsurface rocks in the substrata, reinforced cable conduits should be used for obstacles, or in sandy, loose soil unsuitable for piles. This option longevity and electrical safety. Combiner boxes should be installed has little tolerance for uneven or sloping terrain; hence, site in protected places (beneath the module rows) to mitigate the risk preparation is crucial. Consideration must be given to the risk of of damage caused by UV light and/or heavy snow loads. Where this soil movement or erosion. Once the location of each concrete is not possible, additional covers should be installed to protect the ballast is prepared, no specialist skills are required for installation. 5 I n st a lli n g S o l a r P o we r P l a n ts i n S n o wb o u n d A r e a s : L ess o n s f r o m H i m a c h a l P r a d esh , I n d i a combiner boxes from direct sunlight, rain, and snow. Where snowfall is expected to be heavy, the combiner boxes and inverters can be mounted on high frame structures with a tilted roof cover. Even if oil-cooled transformers have lower losses, dry-type transformers are recommended for Spiti Valley because no environ- A cell architecture known mental problems can be expected in case of damage (oil leakage, as passivated emitter and etc.). However, if oil transformers are used, they must sit on bowls having a capacity of at least 110 percent of the amount of oil in the rear cell (PERC) technology transformer in case of leakages. Cast resin transformers have the is the mainstream option advantage that mechanical defects can be more easily detected for producing high- and repaired. In snowbound areas, heatable transformer stations efficiency solar panels are recommended to protect the transformer and the necessary electrical equipment from the harsh environmental conditions. at competitive prices. Outdoor transformers are not recommended. Transformers should be Bifacial technology is suitable for the altitude and climatic conditions at the site, which may Photo: Stutterstock particularly well suited to necessitate custom-made solutions. Standard equipment is normally snowbound areas because recommended for use only up to an altitude of 1,000 meters and a low temperature of –20°C. foundation (or its dimensions, in case of a concrete slab foundation). of the excellent reflectivity String inverters are recommended for snowbound terrain owing This is also important to determine the right materials and the thick- provided by snow. to their overall weight and plug-and-play features, which allow them ness of the zinc coating. For the rocky terrain of Spiti Valley, concrete to be installed easily by trained workers. They also offer a clear logis- slabs are recommended. No special equipment is necessary for tical advantage: they can be transported easily in a small four-wheel- putting these in place after adequate land treatment. drive truck or lorry, which increases their availability during an already PV modules with frames are recommended for such areas owing limited operational season. They can be installed beneath the module to their ease of installation and handling, and because they are rows for protection from the sun, snow, and rain and therefore need more rigid than frameless modules. Glass-glass modules may also no extra building or foundation (which would be required for a central be considered to avoid micro or complete cell cracks that could be inverter). Inverters should either be sheltered under the module caused by the sag of glass foil modules due to heavy snow loads. tables or, if this is not possible, installed on high stands/frames (at eye For Spiti Valley, modules certified to withstand pressure (snow) loads height or more, depending on snowfall) with a covered roof to protect with a minimum of 5,400 Pascal have been recommended. In May them from direct UV, rain, and snow. In remote sites, fire extinguish- 2020, the International Electrotechnical Commission published a new ers suitable for electrical installations should be provided next to the standard for determining the mechanical performance of framed PV inverters and/or in the transformer station. modules with inclined nonuniform snow loads (IEC 2020). Structural engineering. Structural calculations determine Additional back rails should be included on the module mounting the loads to be transferred through the structure into the ground. structure to support the modules and mitigate the risk of bending Site-specific conditions and wind loads need to be determined. In and breaking under heavy snow loads. An additional back rail placed addition, a soil survey including excavations and sample probes at close to the lower edge of the frame could also mitigate the risk of each site, and at a high resolution, is recommended. Depending on sliding snow tearing out the frame of the module. While the optimal the experience of the surveyor and the complexity of the site, four orientation for one single module row in the Spiti Valley would be a to five sample probes and one excavation per hectare of land are tilt angle of 32° and an azimuth of 180°, depending on the final site recommended to determine the necessary embedment depth of the layout, a minimum tilt angle (for a fixed-tilt system) of 20° to 25° is 6 I n st a lli n g S o l a r P o we r P l a n ts i n S n o wb o u n d A r e a s : L ess o n s f r o m H i m a c h a l P r a d esh , I n d i a recommended to preserve the installed PV panels’ high self-cleaning an access road suitable for trucks weighing up to 40 tons is needed. effect (contaminants cannot stick long to the surface of the PV The heaviest parts of a PV power plant include construction equip- module because of the ethylene tetrafluoroethylene coating). If ment like diggers, transformers, module mounting structures, and seasonal tilt trackers or HSATs are chosen, systems that can change concrete slabs for the foundations of module mountings. the tilt angle between 10° and 35° (or in case of HSATs, between Major implementation issues are discussed below and summa- Transformers should be +/- 55°) are recommended. rized in table 2. suitable for the altitude and In areas with multiple remote project sites, a central logistics climatic conditions at the What specific measures are needed for solar plants in area with year-round connectivity can be identified and a logistics study undertaken to review possible access routes from the central site, which may necessitate snowbound environments? logistics area to the project sites. This site should be fenced and custom-made solutions. Logistical and climatic constraints must be equipped with an operations building where the quantity and quality Standard equipment is accounted for in siting, implementation, operations, of the goods received can be monitored. It should be big enough to maintenance, and monitoring store all the equipment needed at sites that cannot be reached for normally recommended for part of the year. Each site should have an area suitable for preas- use only up to an altitude When implementing solar PV projects in remote, snowbound areas, sembly of cables, connectors, and parts of the module mounting of 1,000 meters and a low buffer times must be considered owing to logistical and climatic structure when work in the field is not possible. For smaller sites constraints that limit the period available to carry out work. Another where the necessary construction and commissioning works can temperature of –20°C. factor to be considered is a site’s access. For instance, in Spiti Valley, be finalized in one row, these areas do not necessarily have to be Table 2. Implementation recommendations Activity Guidance and recommendations Technical comments Logistics Centrally located weatherproof yard for major items. Central yard helps in tracking and transshipment. Also reduces Transshipment to sites using smaller all-terrain trucks. requirements for additional all-weather heavy-duty roads to project locations. Large civil structures Prefabricated structures recommended. Prefabricated structures are modular, faster to install, reduce dependence on local raw materials, and are lightweight but strong. Plot plan and plant Larger interrow distances and provision for medium-duty Will help in mechanical removal of snow using snow ploughs/dozers. layout roads across solar fields. Also reduces chances of shading loss. Tilt angles and Fixed tilt: 20–25°. High tilt helps capture more solar radiation in winters and also aids in tracking Seasonal mechanical tilt: 30–32°. self-cleaning of snow. Quality, health, safety, Very strong protocols need to be agreed upon and followed Considering the distances involved, vagaries of weather, and lack of and environment during implementation period. high-tech medical facilities available at remote locations, extreme management issues care needs to be taken to avoid any industrial accidents like material spillage, physical injuries to staff, and electrical shocks during DC and AC field installation. Plant security Entire plant needs to be monitored using closed-circuit Ingress of wild animals and even local population needs to be television. Perimeter security to be ensured using high-quality monitored strictly. unobtrusive chain link fence with patrolling points and solar- powered lighting at adequate intervals. Lightning protection High-capacity plant-level lightning arrestor needs to be Sudden storms and heavy snowfall can cause electrical short circuits, implemented. so a plant-level lightning arrestor system is extremely necessary. 7 I n st a lli n g S o l a r P o we r P l a n ts i n S n o wb o u n d A r e a s : L ess o n s f r o m H i m a c h a l P r a d esh , I n d i a heated and covered. For larger sites where work is unlikely to finish in one row due to bad weather, partly covered and temperature- and Box 1. Operations and maintenance checklist humidity-controlled areas are recommended. Small warehouses with adequate spare parts (including substruc- • Provision of a central warehouse and control-center with ture and spare modules) and consumables for each site are neces- weatherproof storage facilities for all-season operations and maintenance String inverters are sary for safe storage. Containerized solutions are recommended. The recommended for amounts should be determined in consultation with suppliers. Having • Rigorous preventive maintenance protocols like snow-cleaning the right spare parts on hand is not only important for ongoing after every heavy snow cycle and regular snow removal from snowbound terrain owing solar fields using snow ploughs preventive maintenance but also for corrective and even predictive to their overall weight and maintenance. The operations building may include a warehouse for • Regular monitoring of all data nodes using SCADA and the plug-and-play features, spares as well as an on-site monitoring room where the operation preventive checks of all sensors at string monitoring box and inverter levels to minimize risk of unplanned shutdowns which allow them to be and maintenance staff have an overview of all electrical equipment. This can help reduce reaction times and increase availability. • Five to 7 percent of total modules, and 2.5 percent of string installed easily by trained inverters and string monitoring boxes to be stored as Sufficient clearance (at least 4 meters) should be left between workers. They also offer a operational spares on site at all times to reduce extended module rows to permit machinery to remove snow, with dedicated shutdowns due to the nonavailability of long-lead items and clear logistical advantage: areas close to the gates for piling cleared snow. also considering transportation issues in winter months they can be transported A dirt road along the fence line is important for security and • Periodic checking of the entire plant using drone-mounted maintenance reasons. thermography. easily in a small four-wheel- Exhaustive project documentation is crucial for high-quality and drive truck or lorry. effective operations. The documentation must include the infor- mation specified in IEC standard 62446: Photovoltaic (PV) systems: Requirements for testing, documentation, and maintenance. The provider of operation and maintenance services must • A monitoring system down to the module string level to help have proven ability and experience in large-scale PV projects and detect the exact location of failures and coordinate service in high-altitude locations, and understand the site-specific design, activities electrical configuration, and technical details. An operations and • Closed-circuit television cameras covering the entire PV power maintenance checklist appears in box 1. plant. A unified monitoring system is recommended where multiple Plant-level SCADA or monitoring systems should be made project sites are scattered across an area. Integrating these within available to allow the plant’s visualization and the measurement and one supervisory control and data acquisition (SCADA) system monitoring of results down to the level of the combiner box or mod- streamlines their capacity for comparison and failure detection. ule. Using such systems, with the help of SCADA, a daily comparison Depending on the site, the following equipment and facilities may of the performance ratio and inverter output should be carried out to be needed: help identify production losses such as those due to snow. Regular • At least two cold-resistant pyranometers per 10 megawatts (MW) reports (in some cases, monthly) should contain information on the installed amount of energy produced, irradiation, the performance ratio, a • A measurement station to track the ambient temperature and logbook of failures and outages, and maintenance activities (current input from the module temperature sensors integrated within the and scheduled). SCADA system Installations in snowbound areas require frequent visual inspec- tions and preventive maintenance activities, either whenever the 8 I n st a lli n g S o l a r P o we r P l a n ts i n S n o wb o u n d A r e a s : L ess o n s f r o m H i m a c h a l P r a d esh , I n d i a site is accessible or by officials stationed permanently at the site. During construction as well as operations, it is recommended MAKE FURTHER For project sites in Spiti Valley, quarterly inspections of all the key that all personnel be trained in applicable health and safety mea- CONNECTIONS components of all installed modules are strongly recommended. It sures. This is of particular importance in high-altitude and alpine is also recommended that the modules be cleaned after each bad regions, where the nearest hospital is far away. Live Wire 2015/49. “Promoting Solar weather period using an automated brush system. Inverters with fan Energy through Auctions: The Case of Uganda,” by René Meyer, Bernard cooling should be checked regularly for blockages caused by snow References Tenenbaum, and Richard Hosier. to avoid additional outages. DC and AC combiner boxes should have Bisht, Gaurav. 2020. “Solar-powered water pumps offer ray of hope drying agents to avoid condensation and corrosion. Door sealings Live Wire 2015/50. “Implementing for Spiti’s farmers.” Hindustan Times, August 14. Rooftop Solar Projects: Public-Private and cable entries need to be checked to avoid water ingress and IEC (International Electrotechnical Commission). 2020. “Photovoltaic Partnerships in India,” by Pankaj corrosion. In areas with high wind and snow loads, torque checks of (PV) modules—Non-uniform snow load testing.” IEC standard Sinha, and Shaina Sethi. at least 25 percent of the total screws of the mounting structure are 62938:2020. Accessed August 2020. https://webstore.iec.ch/ Live Wire 2016/61. “Rooftop Solar in recommended. publication/33027&preview. Maldives: A World Bank Guarantee For larger installations (50 MW and above), staff should be Evergy Engineering GmbH. 2020. “Solar Installations in Snow-Bound and SREP Facilitate Private deployed on site at all times. It is also advisable to use drone- Investment in Clean and Affordable Terrain in the Context of Spiti Valley, Himachal Pradesh.” Report mounted thermography to periodically check the entire plant for Energy,” by Sandeep Kohli and Arnaud prepared for the World Bank Group. Evergy Engineering GmbH, Braud. hotspots, major snow accumulation zones, and animal and human Munich, Germany. intrusion. The first thermographic inspection of each year, using Live Wire 2017/72. “What Drives the Gay, Charlie. 2017. “Let it snow: How solar panels can thrive in winter infrared cameras and/or infrared drones, should be scheduled after Price of Solar Photovoltaic Electricity weather.” Office of Energy Efficiency & Renewable Energy, U.S. in Developing Countries?,” by Zuzana the snowy period, when the panels are free of snow, since heavy Department of Energy, January 5. Accessed November 2020. Dobrotkova, Pierre Audinet, and snow loads are a prime cause of damage. Such remote monitoring Gevorg Sargsyan. https://www.energy.gov/eere/articles/let-it-snow-how-solar-pan- tools become more important in areas where accessibility and els-can-thrive-winter-weather#:~:text=A%20dusting%20of%20 Live Wire 2017/82. “Exploiting manpower deployment can pose additional constraints. For smaller snow%20has,PV%20panels%20from%20generating%20power. Synergies between Rooftop Solar PV installations (around 10 MW) this may not be economically viable, so and Energy Efficiency Investments Government of Himachal Pradesh. 2016. H.P. Solar Power a comprehensive closed-circuit television system should be installed in the Built Environment,” by Pedzi Policy—2016. Shimla: Department of Non-Conventional Energy Makumbe. to frequently check for issues such as module soiling or to check the Sources. general status of the site after a storm event. This can also be used Find these and the entire Live Wire to plan maintenance activities. archive at https://openknowledge. worldbank.org/handle/10986/17135.