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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.

With a plethora of technologies emerging in the last decade, while some have relatively matured and proven to be of potential, others are still in evolution. The Industrial Internet of Things (IIoT) has unquestionably triumphed. As is with any new technology introduction, it follows the law of diffusion innovation and the adoption of the technology by the industry follows the S-curve.

Gartner’s Hype Cycle 2011

According to Gartner’s hype cycle, the Internet of Things (IoT) was expected to become ubiquitous and hit a productivity plateau in a ten-year period from 2011.

Today, the prowess of IIoT has been leveraged across various industries and segments, and the energy industry is no exception. There have been various use cases identified and IIoT solutions applied to improve power plant equipment operating efficiency, thereby avoiding plant downtime and also decreasing accidents. The conventional method of scheduled maintenance is flawed in a way that if done too early, it’s a waste of money, and if done too late, it’s a waste of component life. With the introduction of 5G, IIoT coupled with edge computing has resolved the challenge of latency and given the power to compute at source, thereby giving actionable intelligence and significantly improving the processes and personnel’s occupational safety.

Monitoring of power plant assets is crucial in governing its performance. As renewable energy sources are quite intermittent in nature and have a problem of instantaneous mismatch, being able to monitor times of peak load and peak demand and using energy storage technologies to provide power during peak demand is a complex mechanism. Monitoring equipment efficiency with real-time data and getting prompt actionable insights becomes crucial in a successful power plant operation.

The IIoT has numerous applications in energy generation, transmission, and distribution chain. With grid modernization gaining traction, we are at the junction of a challenge. Although IIoT is becoming more cost-effective over time, it still has a long way to go before reaching economies of scale. IoT is fundamentally about the automation, communication, and networking of devices with embedded intelligence, and it will require a significant investment to bring them into the realm of traditional systems.