Bifacial Gains for Fixed Tilt Systems

Bifacial panels are equipped with solar cells on both sides, allowing them to capture sunlight from the front and rear surfaces simultaneously. This innovative design has gained popularity due to recent advancements in manufacturing processes, making them a strong competitor to their monofacial counterparts.

To measure the performance of bifacial solar panels, two key metrics are used: Bifaciality factor and bifacial gain. Bifaciality factor represents the ratio of energy output from the back side of a bifacial panel to the energy output from the front side. On the other hand, bifacial gain measures the percentage increase in energy output of a bifacial panel compared to a Monofacial panel under the same conditions. It demonstrates the panel’s ability to capture and convert light from both sides.

For fixed tilt system projects located in India, the current bifacial gain typically ranges from 3% to 10%. Achieving this gain relies on three fundamental parameters. The most significant parameter is the amount of irradiance received on the rear side and is dependent on the parameters illustrated in the figure above. Furthermore, this in-turn has an impact on area utilized, tonnage of module mounting structures (MMS) and cabling; therefore, it is the skill of the designer to optimize the configuration based on trade-off occurring between the energy gain and the overall impact on plant BOS. SgurrEnergy has the capability to optimize a bifacial based fixed tilt system such that this is realized in terms of least LCOE considering geographical and climatic conditions.

A major parameter that affects the bifacial gain of a solar panels is the albedo, which measures the reflecting power of a surface. Albedo values vary depending on the type of terrain and can fluctuate throughout the year. Different types of surfaces have varying typical albedo values, which have been mentioned in a table below. The third parameter is the view factor, which affects the Bifaciality gain of the solar panel and is directly linked to the positioning and geometry of the solar panels relative to the ground.

To analyze the Bifacial gain from an analytical standpoint, the concept of the normalized height-aspect ratio is often employed. This method ensures that the size of the panel does not matter as long as it is installed at a certain distance from the ground. The higher the panel is installed, the wider the area it can capture sunlight from, resulting in more energy production.

Additionally geometric factors can impact the bifacial gain in fixed tilt condition. One such factor is the obliquity of solar rays impacting the collector, which increases when using a two-panel array compared to a single panel array. This obliquity variation results in less intense reflected irradiance captured by the cells. Additionally, rear mismatch and rear shading factor are two primary parameters that contribute to the adjustment of captured irradiance.

Moreover, the bifacial gain can be further improved by optimizing the installation process based on factors such as open field installations with ample ground space, high albedo or reflective surfaces, fluctuating weather conditions, and a focus on maximizing energy yield and cost-effectiveness.

Bifacial solar panels have become more cost-effective in recent years due to advancements in the manufacturing process. They offer numerous advantages over Monofacial panels, including higher energy yield and stable production; with the difference in costing over monofacial being negligible.

Implementing a bifacial fixed tilt system based on these factors can help optimize energy output, enhance system efficiency, and achieve long-term economic benefits. However, installing bifacial panels with a higher support structure requires consideration of other technical factors such as soil type and wind load.

In conclusion, bifacial solar panels offer significant advantages over their Monofacial counterparts and have the potential to make a significant contribution to the solar industry. By continuing to optimize their design and manufacturing processes and by considering the best installation practices, bifacial panels can continue to evolve and offer even more benefits in the future.

India races toward Net Zero Target of 2070

India’s peak demand this summer is pegged at 229GW; by these estimates it will easily surpass the last year peak demand, and with years to come energy demand will increase. With post pandemic effects cooling off and supply chain issues easing out, India once again cobbles to achieve the set target of net zero by 2070.

Ministry of New and Renewable Energy in its latest statement on 05 April 2023 has announced a plan to add 250GW of renewable energy in the next five years to achieve its target of 500GW of clean energy by year 2030.

This is in line with “India’s Updated First Nationally Determined Contribution Under Paris Agreement”-August 2022 Submission to UNFCCC where 50% of the cumulative electric power installed capacity is planned to be achieved by non-fossil fuel-based energy resources by 2030.
India currently boasts a total renewable energy capacity of approximately 175GW by the end of Feb 2023 which makes an approximately 42% of total energy mix and has committed to increase the energy mix to 50% of 820GW by year 2030.

With the latest statement, the energy mix from renewable energy would be increased from planned 50% by 2030 to approximately 61% by 2030, which is a major push by India to achieve its energy demands through renewable energy. SgurrEnergy observes this shift to be a major step, considering the non-renewable projects not being commissioned or sanctioned in recent past to make the remaining 50% of the energy mix of the basket.

It’s quite evident the industry will race to achieve the set targets for which Government of India has already taken slew of measurements which includes the announcement of the PLI scheme and providing the extension to implement ALMM for the project proponents.

This decision comes with its own risk of completing the projects on record time which will require an efficient use of quality man-power and the technology driven solutions in construction and quality monitoring which shall be engaged in ensuring the quality of the plant being built.

SgurrEnergy boasts a proven track record of providing quality monitoring and project management services through its in-house team that are assisted with agile real time technology driven data sets to be monitored, thereby ensuring the project works are completed on time by apprising the decision makers with the outcomes of the day to day activity being undertaken at the project work site.

We are quite optimistic in achieving the energy targets of the country and the world as a whole.

Reactive Power based LCOE Analysis

The renewable energy sector’s growth in the next 5 years is set to skyrocket according to International Energy Agency (IEA) report1 with Solar Photovoltaic (PV) energy technologies leading the way. This high penetration of Solar PV energy being fed into the electrical grid brings in its share of challenges and is making the grid more and more vulnerable, and unstable, which needs a definitive solution.

The presentation addresses one such challenge, of voltage profile improvement with reactive power compensation at the point of interconnection. The main concern is that solar PV plant PPA’s are with a rating of MWac/MWp and not MVA. IEEE Std 1547/UL 1741 compliant inverters will typically not have reactive power capability & operate with a unity power factor. Though modern inverters are, having the capacity to supply reactive power in the range of +0.8 lead/-0.8 lag, albeit the PV plant is rated based on the AC power supplied by the inverter at unity PF. This leads to an inherent error in the per-unit cost calculation, as when the inverter is providing the reactive power the active power is hampered.

The paper highlights a cost base analysis of various scenarios such as inverters working at unity power factor, plants working with capacitor banks compensation, plants working with an excess number of inverters & plants providing reactive power support with small reactive compensation equipment & a small number of extra inverters. It is concluded that the latter case is the most cost effective and economical.

Watch the whole video here.

Committed to Achieving the Global Vision of a Carbon-Neutral Planet

We have been featured in the APAC Business Headlines magazine Oct 2022 edition.

The planet is warming up. Sea levels are rising, glaciers are melting, cloud forests are dying, and wildlife is struggling to keep up. And the main driver of today’s warming is the increasing emission of greenhouse gases. It has become evident that the majority of the warming over the last century is caused by these heat-trapping gases known as greenhouse gases. Now, to avoid the worst effects of climate change, the world must reduce net carbon dioxide emissions to zero by 2050. It also necessitates a rapid global deployment of renewable energy.

So, as the world progresses toward clean energy adoption and rapid energy transition, SgurrEnergy, a leading engineering consultancy specializing in renewable energy projects, has been an enabler in assisting corporations and governments worldwide in realizing their green energy goals. It offers unparalleled advisory, design and multidisciplinary engineering expertise in the development of sustainable engineering solutions, ensuring the highest quality while adhering to strict budget constraints, completing projects on time, and with favorable project economics. “SgurrEnergy’s advisory experts fully comprehend the challenges and dynamics of the global renewable energy industry and extend the thorough benefit to the project developers, owners, and lenders in developing and implementing high-performance renewable energy projects,” opines Arif Aga, the Director of SgurrEnergy.

Read the whole article here.

SECI Tender: Stark Difference in Results and the Need of Curated Analyses

SECI’s 500MW/1000MWh BESS Project was an ambitious tender floated that resulted in competitors bidding quotes that are poles apart. JSW Energy won the tender quoting a INR1.08 million/MW; on the other hand, the highest INR 2.29 million/MW offered by a seasoned player. The difference in quotes is more than 100%!

This signals the fact that curated modelling, analyses, and optimization of BESS is crucial to gain a competitive edge in energy storage bids. Furthermore, inclusion of RE sources: wind and solar in recent BESS bids, which have high intermittency can affect the hybrid mix and cumulative capital costs.

We help developers accurately size the hybrid mix: RE (PV + WIND) + BESS, by analyses of 20+ years’ time series data on a granular level for PV plants and Windfarms. 

Figure below illustrates the variability of State of Charge (SoC) when coupled with RE to meet peak demand.

We use 25-year simulations to optimally size batteries considering calendar and cyclic degradation profiles specific to OEM make and chemistry thereby removing uncertainties corresponding to “thumb rules” in BESS.

The most effective use of a storm drainage system can be carried out by optimization. By considering the environmental and topographical condition at project site, significance and probability of flood risk, most optimized way of storm drainage system can be adopted.

In a Low lying solar PV project site, Mechanical dewatering (pumping) may be the only option, however cost of pumping station, fuel/electricity may be significant. Failure in pumping system due to any reason may lead to flooding. As the overall area in and around the project site is low lying and flooded, disposal of site runoff outside the project boundary may not additionally impact the adjacent area. However, it need to be verified before planning the mechanical dewatering.

If the Project site has a Uniform outward slope, Drainage system can be avoided by treating local depressions in the site by cutting and filling. However, if the site strata are rocky or soil for the backfilling is need to bring from outside, then cost of cutting and backfilling may be significant.

In the case of a highly mild slope or flat ground where the project site is built, the only way is pumping water outside the project boundary which may increase the flood significance in the adjacent land and may lead to property damage. Therefore, mechanical dewatering (pumping) may also not feasible to drain the site runoff. In such condition, infiltration ponds and infiltration trenches may be a solution to explore. Infiltration ponds and trenches may be created in the entire project site at several locations uniformly. After each rainfall event, the pond and trenches may get filled with water and it shall get infiltrate and evaporate completely or partially before the next rainfall event. However, this solution may require huge land, good infiltration rate of soil, high temperature, low humidity and adequate gap between consecutive rainy days etc.

For a Steep gradient land in and around the project site, Increase in drainage section and requirement of good lining material may increase the cost. Cost of drain at such site condition may be minimized by providing detention pond. Runoff water reached to the project site from the external catchment area may be collected in detention pond. Small outlet may be provided at the bottom of the detention pond and may be discharged into the site drain. As the outlet to the detention pond will be small, small section of drain may adequate to cater the discharge from the detention pond. As the outlet to the detention pond will be small and volume and rate of runoff water entering into the detention pond will be huge, water level in the detention pond may raise rapidly. Therefore, area and depth of detention pond may require huge. Water level in the detention pond may slowly lowered down after the rainfall event and detention pond may completely dry before receiving runoff water from the next rainfall event. Detention pond may be simply excavated to minimize the cost, however, higher requirement of land area for the detention pond may increase the cost. Also security fence or barricade may need to provide all around the detention pond.

For a Steep gradient land around the project site (i.e. in the external catchment area), but mild gradient land in project site, sectional requirement may increase which may require higher land/space to accommodate the drain. Un-lined drain may also be suitable, if the soil is cohesive non swelling. Drain sectional requirement may also be higher due to huge runoff from the external catchment. Therefore, to control the drain section, detention pond in this case may be a good solution.

Low lying site-
Runoff water may not discharge effectively by gravity from low lying area. Therefore, rainfall with small intensity or small duration may lead to significant depth of flooding or significant inundated area at such locations. If there is no waterbody nearby the project site with bed level suitable to discharge the runoff water from the project site, then gravity drains may not be feasible at such locations. Backfilling the entire site land to avoid the flooding may not be economical, may not good for foundations and may take significant time for backfilling. Mechanical dewatering (pumping) may be the only option in such a case, however cost of pumping station, fuel/electricity may be significant. Failure in pumping system due to any reason may lead to flooding. As the overall area in and around the project site is low lying and flooded, disposal of site runoff outside the project boundary may not additionally impact the adjacent area. However, it need to be verified before planning the mechanical dewatering.

Uniform outward slope–
In such case, even if significant external catchment area is governing runoff to the project site, runoff water can be drain outside the project site by gravity. Therefore, depth of flooding at such site may not be significant or if it is significant, wetness time may not be significant. However, there may water logging in local depressions. Local depressions can be treated by cutting and filling to avoid drainage system. However, if the site strata are rocky or soil for the backfilling is need to bring from outside, then cost of cutting and backfilling may be significant.

Highly mild slope or flat ground-
Due to flat land, there may not be defined flow path and therefore, there may not be natural streams exist at such site. Therefore, it may be difficult to discharge the site runoff from such mild sloping or flat land. Pumping water outside the project boundary may increase the flood significance in the adjacent land and may lead to property damage. Therefore, mechanical dewatering (pumping) may also not feasible to drain the site runoff. In such condition, infiltration ponds and infiltration trenches may be a solution to explore. Infiltration ponds and trenches may be created in the entire project site at several locations uniformly. After each rainfall event, the pond and trenches may get filled with water and its shall get infiltrate and evaporate completely or partially before the next rainfall event. However, this solution may require huge land, good infiltration rate of soil, high temperature, low humidity and adequate gap between consecutive rainy days etc.

Steep gradient land in and around the project site–
Provision of drainage system may minimize the flood significance. On steep gradient land, drains can be provided with higher slope and higher velocity. Higher velocity may require lower drain section and good lining material. However, if the external and site catchment area is very huge and land has steep gradient, then huge runoff may govern in short duration. Therefore, drain sectional requirement may increase significantly despite maintaining high velocity. Increase in drainage section and requirement of good lining material may increase the cost. Cost of drain at such site condition may be minimized by providing detention pond. Runoff water reached to the project site from the external catchment area may be collected in detention pond. Small outlet may be provided at the bottom of the detention pond and may be discharged into the site drain. As the outlet to the detention pond will be small, small section of drain may adequate to cater the discharge from the detention pond. As the outlet to the detention pond will be small and volume and rate of runoff water entering into the detention pond will be huge, water level in the detention pond may raise rapidly. Therefore, area and depth of detention pond may require huge. Water level in the detention pond may slowly lowered down after the rainfall event and detention pond may completely dry before receiving runoff water from the next rainfall event. Detention pond may be simply excavated to minimize the cost, however, higher requirement of land area for the detention pond may increase the cost. Also security fence or barricade may need to provide all around the detention pond.

A Typical Wet Detention pond

Steep gradient land around the project site (i.e. in the external catchment area), but mild gradient land in project site-

Provision of drainage system may minimize the flood significance. On mild sloping site land, drain may have low velocity which may minimize the drain lining requirement. However, sectional requirement may increase which may require higher land/space to accommodate the drain. Un-lined drain may also be suitable, if the soil is cohesive non swelling. Drain sectional requirement may also be higher due to huge runoff from the external catchment. Therefore, to control the drain section, detention pond in this case may be a good solution.

Flood significance and its occurrence is highly dependent on environmental and topographical conditions at project site. Intensity of rainfall and maximum daily rainfall may be less if there is uniform distribution of annual and seasonal rainfall throughout the year and season. Lower rainfall intensity or lower daily rainfall minimizes the risk of flooding. Irrespective of rainfall distribution, there may historical peak intensity rainfall, cloudburst, etc. which may lead to significant flooding.

Site topography i.e. direction and significance of land gradient, water bodies in or near by project site, shallow ground water table, soil permeability, land cover etc. also have great influence on flooding and the inundated area. Shallow ground water minimizes the rate if infiltration and increases the time of wetness. Non cohesive soil shall have higher rate if infiltration, whereas cohesive soil shall retain the water. Vegetation may delay the runoff water to reach to the waterbody from the furthest point of rainfall. Runoff water may evaporate slowly if the temperature is low and humidity is higher. The most important factor that influences the flooding is direction and magnitude of land gradient.

Low lying site- If the site is low lying i.e. ground adjacent to all around the project site is at higher elevation and sloping towards the site, then entire runoff water from the adjacent area may accumulate to project site. In such case, depth of flooding may be significant, if the elevation difference between the site and adjacent ground is significant, whereas inundated area may be significant, if the elevation difference between the site and adjacent ground is less. Higher flood depth may have direct impact on power generation within short time, whereas higher in-undated area may lead to operating revenue loss. This impact may be slowly and may take few months or years.

Uniform outward slope– Runoff water may drain efficiently by gravity if the ground has uniform outward slope (i.e. slope towards the boundary) all around the project boundary or at least in one direction.

Highly mild slope or flat ground- Ground in and around the project site may have mild slope or flat. In such case, external runoff may not enter significantly into the project site. Due to flat land, there may not be defined flow path and therefore, there may not be natural streams exist at such site.

Steep gradient land in and around the project site– There may be site with steep gradient land in and around the project site. Runoff water flows rapidly on steep gradient land. If the project site has huge external catchment area, then significant runoff may reach to the project site in short duration. As the site land has steep gradient, flood depth may not be significant and wetness time may be less. However, flow velocity may be high which may erode the soil around the foundation. Higher flow velocity may also damage the road and may bring significant silt from the external catchment to project site.

Steep gradient land around the project site (i.e. in the external catchment area), but mild gradient land in project site-

If the external catchment is huge in area and has steep slope, but the project site land has mild slope, then the rate of runoff water entering into the site may be higher than the rate of runoff water discharging outside the project site. Therefore, flood depth at project site may be significant and wetness time may also be higher.

Tariff for the Solar PV plant is gradually decreasing globally. Therefore, cutoff in the expenditure on project components which does not directly contribute in revenue generation becomes very essential. Environmental and natural calamities may significantly impact the power generation and operating revenue loss. Non-revenue generating components may secure the loss of generation due to environment and natural calamities. Below sections presents one of such non-revenue generating component ‘Storm Drains’.

Before planning the storm drain, it is necessary to understand whether it is really required. If the absence of appropriate and adequate drainage system can directly or indirectly impact the power generation and leading to operating revenue loss, then need to understand, the significance of the impact, how often the flood risk may occur, is there remedial measures other than providing drainage system mitigating or minimizing the flood risk, is the drainage system feasible and if feasible, can we reduce the system cost.

Direct Impact

Absence of drainage system may lead to flooding/water logging as shown in Figure in the Solar PV plant entirely or locally due to which PV modules, cable joints, cable trench in control room, inverter station, string combiner box etc. may submerged in water and may lead to generation loss and ultimately the direct revenue loss. Any damage to the inverter station may significantly impact the maintenance cost. Repair or maintenance of inverter may take several days which may lead the generation loss for long duration.

Water Logging / Flooding in Solar PV

Ground clearance to the PV module can be increased to avoid the module submergence, however, it may lead to increase in post height in the entire plant. Bed level of cable trench in control room, plinth level of inverter station may be maintained adequately above the ground level/flood level by increasing the plinth height which may not increase the cost of construction significantly. Suspended cable with joints may be supported appropriately above the high flood level to avoid any short circuit and loss in generation. It is also necessary to understand the inundation time, as it will directly influence the power generation.

Indirect Impact

Water logging or flooding may impact on foundations, roads, buried cable in trenches, boundary walls etc. which may lead to indirect operating revenue loss. Submerged foundations may get settled which may result the stresses in mounting structure passing on PV modules. It may impact on PV module performance, its generation capacity and ultimately may lead to revenue loss. Foundations may be designed for submerged condition; however, it may lead to increase in cost of foundation. Foundation on hard and non-cohesive soil may have less impact in submersible condition. Flooding may erode the non-cohesive soil if the ground has steep slopes. Foundations may get exposed due to soil erosion. Provision of drainage system may avoid the risk of soil erosion around the foundation. Instead of providing drains, provision of bunds may minimize the risk of soil erosion, however bunds may lead to waterlogging on upstream side of the bund. In-undated area due to the water logging may not be significant, if the land has steep gradient and if the ground has no steep gradient, there may less probability of soil erosion.

Road in submerged condition may lead to undulations and cracks in the road surface. It may increase the cost of maintenance and all time accessibility at any location. In submerged condition, boundary wall foundation may get settled. Water logging on one side of the boundary wall may lead excess pressure on the wall. Failure in boundary wall may lead to increase in cost of maintenance and there may increase in risk of theft. Thus the waterlogging/flooding may impact the various components of the Solar PV plant with varying significance and their remedial measures may vary in cost.

The climate emergency is a pressing concern that has to be addressed decisively and collectively by all the nations.

Hydrogen Council, a group of leading innovation and technology companies with an umbrella of prominent investors have come along to explore and realize the complete potential of hydrogen energy across various industries in the quest to go net zero. Hydrogen is the only fuel that gives water vapor on combustion and therefore is at the forefront of the global energy transition.

Hydrogen energy is categorized by its many colors. Hydrogen produced using renewable energy is called green hydrogen, the most desired form of hydrogen as it non-polluting thereby accelerating the effort of achieving the net-zero goal. Today, most of the hydrogen produced is using natural gas therefore called grey hydrogen, an undesired and polluting way of obtaining hydrogen. Nevertheless, the projects that have come up recently and are underway have clearly indicated that hydrogen is at the heart of the energy transition, there are also advancements on the technology side that will bring down the cost of hydrogen production over the coming years, the U.S. Department of Energy’s (DOE’s) Energy Earthshots aims for a 111, the Hydrogen Shot initiative has envisioned and aimed to reduce the cost of clean hydrogen by 80%, to $1 per 1kilogram 1 decade. This will have tremendous impact in terms of de-carbonization of the energy economy, will also lead to creation of millions of jobs worldwide.

Hydrogen seems to offer abundant opportunities for investment in the future, creation of jobs, a cleaner and greener planet – a promise for a better future.