Master Thesis
Master's Programme in Energy Smart Innovation in the Built Environment, 120 credits
Feasibility Study of Green Hydrogen Power Generation in Kavaratti Island, India
Construction Engineering with
specialisation in Renewable Energy
ABSTRACT
Controlling greenhouse gas emissions is essential by the introduction of renewable energy sources. The island Lakshadweep in India has been dependent on non-renewable generation of electricity over the years. To make them self-sufficient in the energy sector, the introduction of green hydrogen from wind and solar sources and its storage for sustainable future is a great initiative. The factors such as renewable sources, electrolyzer technology, fuel cells included in hydrogen production are optimized for this project in a cost-effective manner over the existing diesel power generation. The cost comparison of this green hydrogen system with cost of diesel for next 20 years clearly illustrated the importance of renewable energy sources for a sustainable future.
ACKNOWLEDGEMENTS
This study is a result of a Master’s Thesis project by Razif Thekkenthiruthummal Kujnumon and Rinto Cheruvill Baby. We would like to appreciate our supervisor Fredric Ottermo, who haveshown great commitment and valuable support during this project. We would also like to express our gratitude our course director Dr. Mohsen Soleimani Mohseni. Also, great many thanks to civilians in Kavaratti island and other various contacts who have provided us with insights in the hydrogen industry, price indicators and valuable knowledge. Without you, this thesis would not have been possible!
This project ends the chapter for us as students at the Master’s Program in Energy smart innovation in built Environment in Halmstad University. Lastly, we would like to thank all our friends and Professors during our time in Halmstad. You have truly enlightened these years, been an incredible support during the studies and made life outside school so much fun.
Thank you!
ABBREVIATIONS
W Watt
kW Kilo Watt
MW Mega watt
Wh Watt hour
kWh Kilo Watt hour
MWh Megawatt hour
GWh Giga Watt hour
kWh/m2 Kilo watt hour per square metre
m/s Meter per second
MU Mega Unit
$/kW American dollar per Kilo Watt
$/kg American dollar per Kilogram
SPV Solar Power Voltaic
PVGIS Photovoltaic Geographical Information System NUTS Nomenclature of Territorial Units for Statistics
CCS Carbon Capture Storage
PEM Polymer Electrolyte Membrane
TABLE OF CONTENT
1 INTRODUCTION ... 1
1.1 RESEARCH AIM ... 3
2 PREVIOUS STUDY ... 4
2.1 GRAY HYDROGEN ... 4
2.2 BLUE HYDROGEN ... 5
2.3 GREEN HYDROGEN ... 5
2.3.1 Significance of green hydrogen ... 5
2.3.2 Advantages of green hydrogen ... 5
2.3.3 Hydrogen uses ... 5
2.3.4 The challenges of green hydrogen ... 6
2.3.5 Green hydrogen’s future ... 7
3 METHODS ... 7
3.1 WIND POWER ... 7
3.1.1 On shore wind turbines ... 8
3.1.2 Offshore Wind Turbines ... 9
3.2 SOLAR ENERGY ... 9
3.3 ELECTROLYZER TECHNOLOGY ... 10
3.4 STRORAGE TANK ... 12
3.4.1 1. Geological storage ... 12
3.4.2 Materials-based storage ... 13
3.4.3 Liquified hydrogen ... 13
3.4.4 Compressed hydrogen ... 14
3.5 FUEL CELL ... 14
3.5.1 Types of fuel cells ... 15
3.6 CONNECTION TO THE ELECTRICAL GRID ... 16
4 METHODOLOGY ... 17
4.1 DAILY LOAD ... 17
4.2 WIND ENERGY ... 18
4.3 SOLAR ENERGY ... 19
4.4 ELECTROLYZER ... 20
4.5 STORAGE TANK ... 21
4.6 FUEL CELL ... 21
5 ANALYSIS AND RESULTS ... 22
5.1 GREEN HYDROGEN PRODUCTION AND STORAGE ... 22
5.1.1 Energy production capacity of a PV cell ... 22
5.1.2 Wind Speed ... 23
5.1.3 Renewable energy production and Daily load demand ... 25
5.1.4 Electrolyzer ... 26
6 DISCUSSION ... 31
6.1 RENEWABLE ENERGIES ... 31
6.2 ELECTROLYZER ... 32
6.3 STORAGE ... 32
6.4 BIPRODUCTS OF FUELCELL ... 33
6.5 LIMITATIONS ... 33
6.6 FUTURE ... 33
7 CONCLUSION ... 35
8 REFERENCES ... 36
APPENDIX ... 39
LIST OF FIGURES FIGURE 1LOCATION OF KAVARATTI ... 1
FIGURE 2MEAN WIND SPEED OF THE LOCATION ... 8
FIGURE 3SOLAR RADIATION OF THE LOCATION ... 10
FIGURE 4HYDROGEN PRODUCTION METHODS ... 11
FIGURE 5HOURLY ELECTRICITY DEMAND AT KAVARATTI ... 17
FIGURE 6HOURLY AND MONTHLY WIND SPEED AT KAVARATTI ... 19
FIGURE 7MONTHLY SOLAR IRRADIATION ESTIMATES AT KAVARATTI ... 20
FIGURE 9DAILY PV PRODUCTION OF A SOLAR CELL OF 1 KWP AT KAVARATTI ... 22
FIGURE 10DAILY PV PRODUCTION OF A SOLAR CELL DURING MONSOON AT KAVARATTI ... 23
FIGURE 11ANNUAL WIND SPEED AT KAVARATTI AT 10M HEIGHT ... 23
FIGURE 12WIND SPEED DURING LOW PRODUCTION DAYS AT KAVARATTI ... 24
FIGURE 13POWERCURVE OF 4.2MW WIND TURBINE ... 25
FIGURE 14ANNUAL LOAD DEMAND AND RENEWABLE ENERGY PRODUCTION ... 25
FIGURE 15LOAD DEMAND AND RENEWABLE ENERGY PRODUCTION DURING LOW PRODUCTION DAYS ... 26
FIGURE 16CHARGING/ DISCHARGING POWER DISTRIBUTION OF ELECTROLYZER ... 26
FIGURE 17ENERGY WASTAGE WHEN LIMITING ELECTROLYZER ... 28
FIGURE 18ENERGY WASTAGE WITHOUT LIMITING ELECTROLYZER ... 28
FIGURE 19ANNUAL STORAGE LEVELS OF GREEN HYDROGEN ... 29
FIGURE 20SOLAR PV INSTALLATION SKETCH KAVARATTI ... 32
FIGURE 21FUTURE OF FUEL CELLS ... 34
LIST OF TABLES TABLE 1ADVANTAGES AND DISADVANTAGES OF HYDROGEN PRODUCTION METHODS ... 12
TABLE 2ANNUAL ENERGY DEMAND IN KAVARATTI ... 18
TABLE 3ELECTROLYZER TYPES AND IMPACTS ... 27
TABLE 4 OPTIMIZED SYSTEM SPECIFICATIONS ... 29
TABLE 5 UNIT COST OF DIFFERENT COMPONENTS IN THE SYSTEM ... 30
TABLE 6TOTAL COST OF ALL COMPONENTS IN THE SYSTEM ... 31
1 INTRODUCTION
In response to 0.8°C global warming, the rate of sea level rise has roughly tripled over the twentieth century. Since the start of satellite measurements, sea level has risen at a rate of 3.4 millimetres per year, which is about 80% faster than the average. Intergovernmental Panel on Climate Change (IPCC) model projection of 1.9 millimetres per year(Rahmstorf, 2010). The major reason behind this scenario is the rise in green house gases and the resulting climate changes. This sealevel rise is seeking more attention all over the world since many countries especially island areas suffering a lot with this.
For sea shores or lands near to sea must face issues like greater tidal ranges, in particular centennial tides, will lead to periodic floods that will destroy non saline habitats. Increased frequency and amplitude of seawater floods are also expected to be more common with global climate change. Sea-level rise will also increase coastal erosion and saline water intrusion. Furthermore, shoreline retreat will also lead to massive displacement of anthropogenic activities from coasts, which will lead to additional habitat loss further inland (Nerem et al., 2018). In this situation we have taken into consideration about one of the islands in the Union Territory of Lakshadweep (UTL), India named Kavaratti.
The Union Territory of Lakshadweep (UTL) is the lone atoll coral island chain in India. The Lakshadweep archipelago involves the broadest coral reef and atoll framework in the Indian Ocean just as the biggest atoll framework on the planet. Aside from holding huge organic variety and going about as the favorable places for fishery stock, coral reefs additionally go about as the 'characteristic safeguard component' against ocean floods and tempests in the Islands.
The islands are geologically segregated with a most extreme distance of in excess of 400 km from the territory and need to rely upon local resources for nearly everything. Network represents a serious issue, both for the personal satisfaction and for advertising of nearby produce in the islands. The separation from territory influences the portability of individuals for schooling, business, social and strict purposes, clinical treatment and so forth.
The Union Territory of Lakshadweep is headquartered on Kavaratti Island. This island is located between Agatti Island on the west and Andrott Island on the east, at a distance of 404 kilometers (218 nautical miles) from Kochi. It situated between 10 degree 32' and 10 degree 35' N latitude and 72 degree 35' and 72 degree 40' E longitude, having an area of 4.22 square km. Maximum width of the island is 1.6 km and length is 5.8 km with a lagoon having a length of about 6 km (“24x7 power for all Lakshadweep islands,” 2016)
Power generation in Kavaratti is predominantly through diesel generators. Diesel comes from the mainland Kerala, making it costly and the cycle of transportation difficult. The transportation of rapid diesel oil to the islands is troublesome and costly. To meet the peak time necessities and the unexpected emergencies, some amount of diesel got stocked in the island. Thus, sometimes spillages and washing out along with rainstorms negatively affects the land and the sea water around the island. The coasts of Kavaratti is so beautiful and water is extremely clear, the overflows while unloading and stacking of diesel may combine with soil and form dirt in the coastal area which in turn negatively affect its beauty.
Lakshadweep has decided to extend the use of renewables in the islands, so that at least 20%
of the total power demand is met by these alternate energy sources initially and then progress to 100% electrification through renewable energy. Solar energy has a lot of potential in Lakshadweep. There are 11 Solar Power Voltaic (SPV) plants established with capacity of one megawatt. Geographical location, ecological considerations and energy demand pattern of Lakshadweep make solar energy one of the most appropriate options to meet the energy demand of the island. The main limitation for the application of solar-based technology in these islands is the large land area requirement for setting up the solar photovoltaic power plants. The situation in the islands of Lakshadweep is favorable for wave power generation, even as a stand-alone system considering the non-availability of other sources and high cost of diesel power generation (“LAKSHADWEEP ACTION PLAN ON CLIMATE CHANGE,” 2012) In this situation the power generation through renewables and storage will definitely be a crucial step for the well-being of the people and the environment there in Kavaratti.
Worldwide the existing fossil fuel systems and infrastructures may switch to green and reliable systems in the upcoming years completely. Thus, hydrogen energy which is regarded as the future energy source have a key role in this context. This can mitigate the effects of GHG and the storage problem associated with energy to a great extent. In addition, hydrogen is the most abundant element on the earth, it is clean and has the highest specific energy content of all conventional fuels (Campen et al., 2008). Moreover the main benefit of hydrogen over the production is that, it can be manufactured from a number of primary energy sources like solar, wind, biomass, coal and nuclear.
Hydrogen can be produced from a variety of processes associated with a wide range of emissions depending on the technology and energy source used. Today globally there is a
demand of approximately 70 trillion hydrogen over all. Which can have 90% growth applicable for industries including chemical, refineries, metal processing and others because of the CO2 emission regulations. 9% for energy growth due to expected storage of curtailed renewables and 1% for mobility by green hydrogen. Almost 48% of H2 is produced by the Steam Methane Reforming (SMR) process which based on the synthesis of steam and natural gas, 48% by partial oxidation and coal gasification which based on chemical processes on industries. Only 4% of hydrogen is produced by electrolysis and other process(“Hydrogen Solutions,” 2021).
Steam methane (natural gas) reforming has an emission factor of 8.9 kg CO2/kg H2, while coal gasification’s emission factor is even higher, at 29.33 kg CO2/kg H2. Today around 8.2 Metric tonnes of fossil-based hydrogen are produced in the EU- the vast majority of it by SMR from natural gas. Lastly, hydrogen can also be produced by using nuclear energy but this route is linked to high socio-economic risks (Kakoulaki et al, 2021). Thus most of the hydrogen production have nonrenewable fuels or essentials which in turn produce harmful emissions.
Over the years research are going on Hydrogen fuel which is believed to be the future energy carrier. Hydrogen production via water electrolysis process using wind energy is currently adjudged one of the hydrogen pathways with lowest life cycle greenhouse gas emissions with competitive cost of hydrogen production(Mohamed Douaka, Noureddine Settoub, 2015).
Various studies are conducting at different parts of the world to assess the technical and economic analysis of large-scale hydrogen production from renewables. The study assesses the feasibility of producing green hydrogen from solar, wind and hydropower resources assuming a maximum potential at both regional and national level following the 2016 NUTS classification. Nomenclature of Territorial Units for Statistics or NUTS is a geocode standard for referencing the subdivisions of countries for statistical purposes (Kakoulaki et al, 2021)
1.1 Research Aim
This study investigates how to Store renewable energy into Green hydrogen, production and storage for energy supply in Kavaratti Island, focusing on the latter, which can be designed and regulated for optimal utility from a financial and technical perspective. To achieve this, We used MATLAB simulations considering different scenarios. The goal is to determine the best storage option and energy output for Kavaratti, which is dependent on a variety of production factors, demand scenarios, technical and financial factors. The following research questions are examined in order to achieve the study's aim.
To discover the potential of Kavaratti's sustainable energy (Wind and Solar) production Design an optimal storage tank to meet the energy demand in Kavaratti while remaining as cost effective as possible
The final cost comparison between the current diesel generation power plant and the green hydrogen power plant over the next 20 years
2 PREVIOUS STUDY
Hydrogen energy is very flexible, as it can be used as a gas or a liquid, converted into electricity or fuel, and produced in a number of different ways. Hydrogen gas was first produced artificially back in the 16th century, while the first fuel cells and electrolysers were made in the 19th century(“The green hydrogen revolution has started, and it won’t be stopped,2018.).
The first reference we have found to the term green or renewable hydrogen was mentioned by National Renewable Energy Laboratory in 1995, who used the term renewable hydrogen (hydrogen produced from renewables) as a synonym for green. The State of California defined green hydrogen as being produced cleanly and sustainably, using a renewable source such as solar or wind. The first mention of green hydrogen in EU policy documents is the declaration for establishing a green hydrogen economy in Europe in 2007(Velazquez Abad and Dodds, 2020).
Approximately 70 million metric tons of hydrogen are already produced globally every year for use in oil refining, ammonia production, steel manufacturing, chemical and fertilizer production, food processing, metallurgy, and more. There is more hydrogen in the universe than any other element it’s been estimated that approximately 90 percent of all atoms are hydrogen. But hydrogen atoms do not exist in nature by themselves. To produce hydrogen, its atoms need to be decoupled from other elements with which they occur in water, plants or fossil fuels. How this decoupling is done determines hydrogen energy’s sustainability.(Cho et al, 2021)
Hydrogen production is done by separating hydrogen from the other elements in the molecules where it occurs. There mainly three types of hydrogen are present according with sources of production.
2.1 Gray Hydrogen
The majority of hydrogen presently in use comes from a process named as steam methane reforming, which involves reacting methane and high-temperature steam with a catalyst to create hydrogen, carbon monoxide, and a small volume of carbon dioxide. Carbon monoxide, steam, and a catalyst react in a corresponding step to release more hydrogen and carbon dioxide. Since the carbon dioxide and impurities have been separated, pure hydrogen remains. Such fossil fuels, such as propane, oil, and coal, can also be used to generate hydrogen by steam reforming. This fossil-fuel-based method of production produces Gray hydrogen as well as 830 million metric tons of CO2 per year, which is equal to the emissions of the United Kingdom and Indonesia combined.(Cho et al., 2021).
2.2 Blue Hydrogen
Blue hydrogen is produced from natural gas, usually via steam-reforming, with carbon capture storage(CCS). Blue hydrogen has the potential of large-scale, CO2-lean hydrogen production with proven, high TRL technologies. Blue hydrogen still requires fossil fuels and CCS, which are under heavy public debate, however can lead to a significant CO2 reduction.
2.3 Green Hydrogen
Hydrogen can also be produced by electrolyzing water, which produces only oxygen as a by- product. In an electrolyser, an electric current is used to separate water into hydrogen and oxygen. The pollutant-free hydrogen emitted when electricity is generated using renewable energy sources such as solar or wind is known as green hydrogen. One example is the quickly falling cost of green energy attracting rapid interest in the energy sector.
2.3.1 Significance of green hydrogen
According to most of the analysts, the green hydrogen is an unavoidable part to reach Paris Agreement's targets, since some sectors of the economy have difficult-to-reduce emissions.
The top three sources of climate-warming emissions are listed below 1. Transportation
2. Electricity generation 3. Industry.
Energy efficiency, renewable power, and direct electrification can reduce emissions from electricity production and a portion of transportation; but the last 15 percent or so of the economy, comprising aviation, shipping, long-distance trucking and concrete and steel manufacturing, is difficult to decarbonize because these sectors require high energy density fuel or intense heat. Green hydrogen could meet these needs.(Cho et al., 2021)
2.3.2 Advantages of green hydrogen
Hydrogen is abundant and nearly limitless in supply. It can be used on the spot where it's made or shipped to another location. Unlike batteries, which are incapable of storing large amounts of electricity for long periods of time, hydrogen can be produced from excess renewable energy and stored in large quantities for extended periods of time. Because hydrogen has nearly three times the energy of fossil fuels, it takes less of it to accomplish the same task. Green hydrogen also has the advantage of being able to be produced anywhere there is water and enough energy to generate additional electricity or heat.
Hydrogen uses
Green hydrogen can be used in industry and can be stored in existing gas pipelines to power
power anything that uses electricity, such as electric vehicles and electronic devices. And unlike batteries, hydrogen fuel cells don’t need to be recharged and won’t run down, so long as they have hydrogen fuel.
Fuel cells work like batteries: hydrogen is fed to the anode, oxygen is fed to the cathode; they are separated by a catalyst and an electrolyte membrane that only allows positively charged protons through to the cathode. The catalyst splits off the hydrogen’s negatively charged electrons, allowing the positively charged protons to pass through the electrolyte to the cathode. The electrons, meanwhile, travel via an external circuit—creating electricity that can be put to work—to meet the protons at the cathode, where they react with the oxygen to form water.
Hydrogen is used to power hydrogen fuel cell vehicles. Because of its energy efficiency, a hydrogen fuel cell is two to three times more efficient than an internal combustion engine fuelled by gas. And a fuel cell electric vehicle’s refuelling time averages less than four minutes.
Because they can function independently from the grid, fuel cells can be used in the military field or in disaster zones and work as independent generators of electricity or heat. When fixed in place they can be connected to the grid to generate consistent reliable power.(Cho et al., 2021)
2.3.3 The challenges of green hydrogen
Its flammability and its lightness mean that hydrogen, like other fuels, needs to be properly handled. Many fuels are flammable. Compared to gasoline, natural gas, and propane, hydrogen is more flammable in the air. However, low concentrations of hydrogen have similar flammability potential as other fuels. Since hydrogen is so light about 57 times lighter than gasoline fumes it can quickly disperse into the atmosphere, which is a positive safety feature.
It's difficult to transport hydrogen because it's so much lighter than gasoline. To liquefy it, it must either be cooled to -253°C or compressed to 700 times atmospheric pressure before being delivered as a compressed gas. Currently, hydrogen is transported via dedicated pipelines, low-temperature liquid tanker trucks, and gaseous hydrogen tube trailers.
Because hydrogen can make steel pipes and welds brittle and cause cracks, natural gas pipelines are sometimes used to transport only a small amount of hydrogen. Hydrogen can be safely distributed through natural gas infrastructure when less than 5% to 10% of it is blended with it. To distribute pure hydrogen, natural gas pipelines would require major alterations to avoid potential embrittlement of the metal pipes, or completely separate hydrogen pipelines would need to be constructed.
Fuel cell technology has been constrained by the high cost of fuel cells because platinum, which is expensive, is used at the anode and cathode as a catalyst to split hydrogen. Research is ongoing to improve the performance of fuel cells and to find more efficient and less costly materials.(Cho et al., 2021)
A challenge for fuel cell electric vehicles has been how to store enough hydrogen—five to 13 kilograms of compressed hydrogen gas—in the vehicle to achieve the conventional driving range of 300 miles.
2.3.4 Green hydrogen’s future
The popularity of Green hydrogen storage increasing in the sustainable industry sector around the world. These initiatives are advancing our understanding of how to generate hydrogen and other forms of this largely renewable fuel to power our future.
Biological hydrogen (biohydrogen) production using (micro) organisms is an exciting new area of technology development that has the potential to produce usable hydrogen from a variety of renewable resources. Direct biophotolysis, indirect bio photolysis, photo-fermentations, and dark-fermentation are just a few of the methods used by biological systems to generate hydrogen.
3 METHODS
3.1 Wind Power
Wind have a great potential to cover all the energy requirements in the world. Wind can be easily utilized for the generation of power, it is renewable, clean, widely available and easy to capture. Wind power, like solar energy, accounts for a small portion of overall energy reaching the earth. Over the past few years wind-based power generation has increased to multi-fold level. Despite of the remarkable growth of wind energy there are many challenges for researchers, such as grid integration, unpredictable nature of wind, and the location of wind turbine. More advanced modern generators, power converters and controllers have to be developed to penetrate the wind turbine into the power grid (Ramji Tiwari, 2016).
When the sun's rays heat the air in the atmosphere unevenly, wind blows. The equator receives direct sunlight and receives more heat than other areas of the globe. Warmer equatorial air rises and generates a low pressure system. The air flows in to the low pressure area created at the equator by the rising of hot air in the northern and southern hemispheres.
At the same time, the rotation of the earth produces a Coriolis effect, which causes air to migrate to the east in the northern hemisphere and west in the southern hemisphere.
Geostrophic winds up to 1 km above ground are created by the combination of unequal heating of tracts and the Coriolis effect, and they are generally the dominant winds in each area. Fig 1 shows the mean wind speed at a height of 100m around the globe.
Figure 2 Mean wind speed of the location (“Global Wind Atlas,” 2021)
3.1.1 On shore wind turbines
Onshore wind turbines, a type of turbine that is mounted on ground, have tower heights of 50–100 meters and rotor diameters of 50–100 meters . The current trend in wind turbine design is to Increase the height of the tower and the length of the rotor blades. The modern wind turbines consist of the components like
• Steel, concrete or hybrid towers.
• An upwind rotor with three blades, active yaw system, preserving alignment with the wind direction. Rotor efficiency, acoustic noise, costs and visual impact are important design factors.
• Controlling high wind speeds. Pitch regulation is an active control that regulates extracted power and reduces loads by pitching the blades along their axis (flapwise).
• Variable rotor speed, which allows optimizing the energy capture at low-wind speeds (by operating at maximum power coefficient) also reducing mechanical loads on the drive train.
• The drive train converts the mechanical power captured by the rotor into electric power.
By this the wind turbines are classified as
(i) geared wind turbine with induction generator that is fed twice (DFIG). The gearbox converts the blades' slow rotating speed into the high rotational speed required by standard induction generators in this configuration. A partial power converter allows you to adjust the speed of the electric generator to match the rotational speed of the mechanical system.
(ii) Configuration with no gears or direct drive. Without the use of a gearbox, a synchronous generator, either electrically excited or using permanent magnets, is directly coupled to the main shaft (i.e. spinning at the same speed as the turbine rotor). A full-power converter connects the electric generator to the grid, adapting the variable voltage of the electricity generated to the grid frequency.
(iii) Hybrid configuration. Slow rotating electric generators require a large number of poles that are translated into larger generator diameters (and hence heavier machines). This issue is even more pronounced in large wind turbines where the rotational speed of the blades is slower. Alternatively, in the case of geared wind turbines, higher speed conversion ratios imply more demanding operating conditions for the gearbox components and bearings. A compromise solution can be achieved by this hybrid configuration equipped with a gearbox which converts the blades' slow rotational speed to a medium/high-speed generator with a full converter. (Serrano-González et al, 2016)
3.1.2 Offshore Wind Turbines
While offshore wind energy has been around since the 1990s, it is only now beginning to develop in different ways depending on the region. This got favored due to number of important factors: the land's minimal room, less general environmental effects etc. Off-shore power systems are wind turbines built beyond the coast. Offshore winds are faster and more uniform than on land, thus offshore sites can build larger power plants with larger wind turbines. The major concern about offshore farms is that they are much more complicated in the sea, not only of design but also in terms of construction and service.
The second benefit stems from the larger available free areas in the sea where offshore wind turbines can be built, allowing for more installations regardless of the land accusation cost.
Its location (far from population areas) allows for a reduction in noise emissions, which is good for the atmosphere.
On the contrary, the first disadvantage is the cost of the permitting and engineering process, and of the construction and operation phases. In onshore wind farms, the cost of wind generator turbines is around 75% total cost of the Project, being this percentage in offshore installations approximately 33%, which can be explained as mainly due to the high costs of the sea operations. Besides, unlike onshore wind farms, there are not usually marine electrical infrastructures that connect the highest wind resource areas with the consumer centers, leading to the construction of longer electrical networks, and even to strengthen the existing electrical infrastructures (Esteban et al., 2011).
3.2 Solar energy
Solar energy has the potential to be the most widespread renewable energy source available to humankind, and hydrogen generation from solar energy is seen as the ultimate solution for long-term energy sustainability. Many researchers have been involved in analyzing the different solar hydrogen production methods based on energy and exergy analysis(Koumi Ngoh and Njomo, 2012). The improvement of the techniques for hydrogen creation dependent on environmentally friendly power sources happens, however much as could be expected without delivering the ozone harming substance. These advances empower the transformation of solar radiations in to heat up to a temperature ranging between 200 C and 2000 C with a greatest efficiency of 70%. This primary heat will be changed over to an energy vector of hydrogen.
Figure 3 Solar radiation of the location
(“JRC Photovoltaic Geographical Information System (PVGIS) - European Commission,” 2021) Solar power generation carried out by the utilization of photovoltaic (PV) cells or by gathering the solar power (CSP) to create steam which is then used to drive a turbine to give the electrical force. The photovoltaic effect, which refers to the fact that photons of light knock electrons into a higher state of energy, is used to generate direct electricity from solar energy.
Although photovoltaics were first used to power spacecrafts, there are numerous PV power generation applications in everyday life, such as grid-independent homes, water extraction pumps, and electric cars, roadside emergency telephones and remote sensing (Camacho and Berenguel, 2012). This power generation by solar is used for the production of hydrogen in this project.
3.3 Electrolyzer Technology
As we mentioned in the pre study there are several type of hydrogen production technics are currently available Hydrogen has been produced from various renewable and non-renewable energy resources such as fossil fuels, primarily steam reforming of methane, oil reforming, coal gasification, biomass, biological sources and water electrolysis. The various comprehensive hydrogen production methods. The various comprehensive hydrogen production methods (Figure. 4) along with their advantages, disadvantages, efficiency and capital cost are provided in Table 1(“Hydrogen production by PEM water electrolysis “ A review | Elsevier Enhanced Reader,”2019). Currently approximately 96% of the global hydrogen production from non-renewable fossil fuels, in particular steam reforming of methane. However, the usage of fossil fuels, they produces lower purity of hydrogen with high concentration of harmful greenhouse gasses. Furthermore, to meet the world's ever- increasing energy demands and limited fossil fuel reserves, as well as to ensure long-term sustainability and minimal environmental impact, new energy approaches without carbon
emissions must be developed. Nowadays has taken attention as an environmental friendly energy strategies which possibly to replace the current fossil fuel based energy pro-duction, this can be achieved by when the hydrogen is produced from the renewable water. Water electrolysis produces pure hydrogen and oxygen and is an environmentally friendly and high purity hydrogen production method (99.999 percent).
(“Hydrogen production by PEM water electrolysis “ A review | Elsevier Enhanced Reader,”
2019)
Figure 4 Hydrogen production methods
Water is one of the many raw materials that can be used to make hydrogen. Water electrolysis is one of the hydrogen extractions processes that are both environmentally safe and produces high purity hydrogen. PEM water electrolysis was considered one of the most promising techniques for high pure, efficient hydrogen output from clean energy sources regarding sustainability and environmental effects. And emits only oxygen and hydrogen as a byproduct and contributing less CO2 emission comparing to other Water electrolysis methods
Table 1 Advantages and disadvantages of Hydrogen production methods
(“Hydrogen production by PEM water electrolysis “ A review | Elsevier Enhanced Reader,”
2019)
Increased interest in PEM water electrolysis has begun to grow as the need to produce green hydrogen has emerged. As a result, significant research into the production of cost-effective electro-catalysts for PEM water electrolysis is developing day by day
3.4 Strorage tank
Hydrogen has the highest energy content by weight, and when used in fuel cells produces only water as a byproduct. Another feature of hydrogen is that it can be stored in small and large quantities by a number of methods. In addition, hydrogen can be produced by a diverse mix of energy sources, and can play an important role in energy storage and U.S. energy security(Barthelemy et al., 2017)
The storage of hydrogen is challenging. Being the lightest molecule, hydrogen gas has a very low density: 1 kg of hydrogen gas occupies over 11 m3 at room temperature and atmospheric pressure(Schlapbach and Züttel, 2010)
There are many types of storage technics are available today among those four types of storage are popular and economically viable. They are described bellow
3.4.1 1. Geological storage
Advanced Clean Energy Storage, the world's largest renewable energy storage project, was recently announced and will be located in Utah, United States. Advanced Clean Energy
Storage will show off technologies that will be critical in a future decarbonized power grid. as Excess renewable energy hydrogen will be stored in a series of underground salt caverns. part of the project. Enough renewable hydrogen will be stored in a single cavern to provide 150,000 MWh of clean energy storage. Mitsubishi Hitachi Power Systems will supply the technology for converting excess renewable electricity into 'green' hydrogen. Storage of gas in salt caverns is a well-established technology that facilitates knowledge transfer.(“Micro- H2,” 2011)
3.4.2 Materials-based storage
An alternative to compressed and liquified hydrogen storage is materials-based storage. This technique uses materials – solids or liquids – that can absorb or react with hydrogen to bind it, due to their chemical attributes.
At the University of California, Berkeley, research is underway to create an adsorbent that will allow a light-weight, inexpensive pressure container to be used in hydrogen-powered cars, for example, in lieu of the large, heavy containers currently in use.
Ammonia is another material that offers a path to turning hydrogen into a liquid fuel more easily than using liquefaction. Ammonia’s energy density by volume is nearly double that of liquefied hydrogen, making it far easier to store and transport.(Industries, 2020)
Among these It has been discovered that pressure vessel technology is advantageous because it is simple to incorporate and provides high storage energy efficiency at a low cost.
The goal of ongoing research is to develop high-strength and light-weight materials for pressure vessels with higher volumetric and gravimetric storage densities. In order to avoid hydrogen embrittlement, the new materials must be chemically inert to hydrogen.
3.4.3 Liquified hydrogen
Liquefied hydrogen gas can be stored in a thermally insulated vessel. Hydrogen storage in liquid form has higher volumetric and gravimetric storage densities than compressed hydrogen gas storage. The inversion temperature of 202 K is reached by compressing and cooling hydrogen gas. At a boiling point of -253oC, subsequent expansion results in the formation of cryogenic hydrogen liquid (20 K).The energy storage density has been estimated to be 5 MJ/litter(Ni, 2006a)
Liquid hydrogen storage is technically challenging and, as a result, has been prohibitively expensive in the past.
To date, the use of liquified hydrogen has been limited due to its complexity and high cost.
However, with the anticipated proliferation of green hydrogen applications, liquefaction
3.4.4 Compressed hydrogen
Gaseous fuels are commonly stored by compressing them to a small volume and high pressure. The energy requirement appears to be the difference between hydrogen compression and compression of other conventional fuel gases like natural gas and town gas.
The specific gravity of hydrogen is lower than that of other fuel gases., it takes more energy to compress hydrogen for given mass and compression ratio(V and Jj, 2005)
The volumetric storage density (H2-kg/m3) increases as the hydrogen storage pressure is increased, but the overall energy efficiency decreases. Steel vessels with operating pressures up to 700 bar are commonly used for high-pressure gas compression storage. Steel, on the other hand, is not a good choice for hydrogen storage. Because hydrogen diffusion into steel causes hydrogen embrittlement failure, especially when the vessels are charged and discharged frequently, this is the case. Steel projectiles can cause serious injuries if they rupture. Furthermore, the gravimetric storage density, defined as the ratio of the mass of stored gas to the mass of vessel, is low, normally in an order of 0.01 H2-kg/kg. (Ni, 2006) The hydrogen embrittlement problem can be resolved by using vessels made of composite materials comprised of polyethylene, or carbon fiber and epoxy resin with thin aluminium liner(Ni, 2006)
For a certain application needs a smaller amount of hydrogen than compression can provide, it can be liquefied. Compression and liquefaction are two methods that can be combined.
For this project we considered Compressed hydrogen storage system. It is ideal for the project and cost-effective method while comparing to the other types of storage systems. After analysing all the storage system, it is clear that the initial investment for building a storage tank for the green hydrogen system quite expensive. However, the cost for hydrogen storage may further decrease in years to come, and particularly in storage applications as large as that considered for this case study.
3.5 Fuel cell
A fuel cell is an electrochemical system that generate electricity rather than combustion.
Hydrogen and oxygen are mixed in a fuel cell to provide energy, heat, and water. Fuel cells are used in a variety of applications today, from supplying electricity to households and industries, maintaining vital infrastructure such as hospitals, grocery stores, and data centers, transporting automobiles, buses, trucks, forklifts, trains, and other vehicles.
Fuel cell systems are a power source that is renewable, effective, dependable, and quiet. Fuel cells, unlike batteries, do not need to be recharged on a regular basis; instead, they continue to generate energy as long as a fuel supply is available.
An anode, cathode, and electrolyte membrane make up a fuel cell. In a typical fuel cell, hydrogen is passed through the anode and oxygen is passed through the cathode. A catalyst splits hydrogen molecules into electrons and protons at the anode Protons pass through the
porous electrolyte membrane, while electrons are forced through a circuit, As a result, an electric current is generated, as well as an excess of heat. At the cathode, protons, electrons, and oxygen combine to form water molecules. Fuel cells works silently and with high reliability because they have no moving parts. (“Fuel Cell Basics,” 2020)
Fuel cells are extremely clean due to their chemistry. Fuel cells that use pure hydrogen as a fuel are carbon-free, producing only electricity, heat, and water as byproducts. Hydrocarbon fuels such as natural gas, biogas, methanol, and others can be used in some fuel cell systems.
Fuel cells can achieve much higher efficiencies than traditional energy production methods such as steam turbines and internal combustion engines because they generate electricity through chemistry rather than combustion. A fuel cell can be combined with a combined heat and power system that uses the cell's waste heat for heating or cooling to increase efficiency even further.
Fuel cells can also be scaled up. Individual fuel cells can be linked together to form stacks in this way. These stacks can then be combined to form larger systems. Fuel cell systems range in size and power from small-scale, multi-megawatt installations that provide electricity directly to the utility grid to large-scale, multi-megawatt installations that provide electricity directly to the utility grid.
3.5.1 Types of fuel cells
The classification of fuel cells are based on the kind of electrolyte used in fuel cells. This classification specifies the type of electrochemical reactions that occur in the cell, the type of catalysts needed, the operating temperature spectrum, the fuel required, and other factors.
These properties have an effect on the applications that these cells are best suited for. There are several types of fuel cells in production right now, each with its own set of benefits, drawbacks, and possible applications.
3.5.1.1 Stationary Fuel cell
Stationary fuel cells provide clean, efficient, and reliable off-grid power to homes, businesses, telecommunications networks, utilities, and others through an electrochemical reaction rather than combustion. Many companies around the country are adopting fuel cells for primary and backup power including: Adobe, Apple, AT&T, CBS, Coca-Cola, Cox Communications, Delmarva Power, eBay, Google, Honda, Microsoft, Target and Walmart, among others. According to FCHEA’s tracking and surveys, as of January 2020 there are more than 550 megawatts (MW) of stationary fuel cells installed in the United States providing clean, reliable, distributed power to customers across the country.(“Stationary Power,” 2020) Stationary fuel cells are silent and emit almost no pollution, allowing them to be deployed almost anywhere. These networks provide electricity to consumers on-site, avoiding the
In comparison to other renewable energy technology, stationary fuel cell systems take up much less volume. A 10 MW fuel cell installation, for example, can be built on around an acre of land. As opposed to solar power, which requires about 10 acres per MW, and wind power, which requires about 50 acres per MW.
Fuel cells are very powerful, with a typical fuel-to-electricity ratio of 60%, almost twice that of current diesel power generator(“Diesel generator,” 2021). Fuel cells produce heat as well, which, if captured, will boost total energy efficiency to over 90%. The heat generated by fuel cells may be used to generate additional energy through a turbine, or to provide direct heating to nearby buildings or facilities, and even cooling with the addition of an absorption chiller.
Stationary fuel cells, unlike combustion-based power generation, produce almost no emissions. Particulate emissions, unburned hydrocarbons, and acid rain-causing gases are not produced by fuel cells. Fuel cells release less carbon emissions than other, less effective systems, and when powered by green fuels like biomass, they are carbon neutral.
Fuel cells are being introduced by government plant operators in order to meet statutory air quality targets because of these sustainability advantages. Fuel cell systems are widely being used by utilities and businesses to meet state clean energy standards and emission specifications.
3.6 Connection to the electrical grid
The fundamental electrical network has a steady recurrence of 50 Hz or 60 Hz and a steady stage point. A wind turbine should deliver power with similar steady qualities to be coordinated into the fundamental network. The performance of a wind turbine is relative to the wind speed, however the wind speed is rarely steady. Each wind speed has a comparing rotor revolution speed, at which the greatest force is delivered. This most extreme happens for various wind speeds at various paces of revolution. In any case, the pace of revolution should be held consistent to accomplish the necessary steady yield recurrence or the wind turbine must be associated with the lattice by doubly took care of offbeat generator or by electronic recurrence converters.
Normally megawatt turbines are not able to connect to the grid at 0.4 kV; instead, they must be connected at 10–30 kV, which is the standard level of city electricity distribution. The wind park developers must build and finance a 30 kV connection in remote areas which does not exist.. Wind parks with a lot of Megawatt turbines can also be connected into the electrical grid. As mentioned earlier the maximum power output is obtained only for some hours during the year (Wagner, 2017).
4 METHODOLOGY
4.1 Daily load
To collect the data for the Daily load, the fundamental step we have taken, calculated the hourly load data from the internet. We considered the nearest state Kerala almost living style is identical to Lakshadweep condition. Climate also is similar in both places, and interviewed few residents from the Kavaratti, as per Lakshadweep climate, understood that there two main monsoon seasons are available in the region. The tropical climate of Lakshadweep is pleasant, with summer temperatures ranging from 22° C to 33° C and winter temperatures ranging Temperatures range from 20 to 32 degrees Celsius. From June to September, the southwest monsoons bring a lot of rain to the islands. The months of October to May are pleasant, with plenty of sunshine. a slight rise in temperature during March and April(“Society for Promotion of Nature Tourism and Sports - Lakshadweep Tourism,” 2007)Summertime, especially in the March to June the amount of energy used daily changes in predictable ways over the year. The total hourly electricity load in the Kavaratti usually is higher during the summer months almost 60% of hike , as demand increases in the afternoon when people and companies use air conditioning on hot days. As a result, we are considering the fact that electricity consumption will increase by 60% this summer compared to normal winter conditions.
During the winter months, hourly electricity load is variable in the morning and the evening.
Morning time 7 am to 8 am its recorded over 2 kWh, The evening time electricity demand surges from 5 p.m. to 11 p.m., with the highest peak between 7 p.m. and 11 p.m.
When compared to electricity demand in the evening, it reached over 4kWh, which is double the amount of demand in the morning.
Figure 5 Hourly electricity demand at Kavaratti
constant electricity is required by machines such as refrigerators and other electronic equipment that constantly operates.
Table 2 shows the energy requirements for Kavaratti in that we take in to account 2019 figures. Generated the daily load energy consumption of Kavaratti in the winter and summer based on the estimated daily needed energy for the Kavaratti, which matched the qualitative analysis we conducted and the daily load consumption pattern from Kerala.
A year-long hourly time series 𝑃! for the load was estimated from the mean load and summer load, seen in figure 5, according to:
𝑃! = (2𝑃!,#− 𝑃!,$) sin% (𝜋 𝑖/𝑁) + 𝑃!,$ cos%(𝜋 𝑖/𝑁),
where 𝑖 is the hour, 𝑁 is the yearly number of hours, and 𝑃!,# and 𝑃!,$ are a year-long time series based on the mean and summer load patterns, respectively, as seen in figure 5.
Table 2 Annual energy demand in kavaratti (“24x7 power for all Lakshadweep islands,” 2015)
4.2 Wind Energy
To take the wind data of Lakshadweep for the years we have chosen the Global wind atlas as the reference tool. The Global Wind Atlas is a free, web-based tool designed to assist policymakers, planners, and investors in locating high-wind areas for wind power generation virtually anywhere on the planet, as well as performing preliminary calculations. The Global Wind Atlas allows users to conduct online searches and download datasets based on the most up-to-date input data and modeling methodologies.(“Global Wind Atlas,” 2021.)
The average wind speed at Kavaratti Lakshadweep (latitude: 10.56, longitude: 72.63) is around 5m/s at 100m height.
Particulars Energy and Demand Scenario
FY16 FY17 FY18 FY19
Sale within State (GWh) 10.69 11.60 12.66 13.92
Distribution losses 9.12% 8.87% 8.62% 8.37%
Total Energy Requirement with in Island
(GWh) 11.76 12.73 13.86 15.20
Load Factor 70.68% 70.68% 70.68% 70.68%
Maximum Demand (MW) 1.90 2.06 2.24 2.45
Figure 6 Hourly and monthly wind speed at Kavaratti (“Global Wind Atlas,” 2021)
From figure 6, it shows that during the months June to august the wind availability is high compared to other months. In these months the wind speed remains around 10m/s which is favourable for proper wind power generation. But the hourly wind data collected from this source is replaced with the data collected from PVGIS for the simulation in Matlab for the optimum wind power and electricity generation. It is because the time series for wind speeds is available from PVGIS, but a time series is not available from Global Wind Atlas. Also, the mean wind speed differs between the sources. GWA is considerably lower than PVGIS, the latter is however on par with other sources. So PVGIS data is deemed adequate in this case.
For the ease of calculation, the latest available data for the year 2016 is taken into consideration for the analysis and simulation process.
4.3 Solar Energy
Lakshadweep islands have a great exposure to sunlight and have a potential to harvest solar energy. To calculate this availability and utilization we have taken Photovoltaic Geographical Information System (PVGIS) as the base for the data and calculation. PVGIS is a web application that allows users to obtain information on solar radiation and photovoltaic (PV) system energy production from any location in the world.
The solar irradiation at Kavaratti Lakshadweep (latitude: 10.56, longitude: 72.63) will vary throughout the year according to seasons (figure 7).
Figure 7 Monthly solar irradiation estimates at Kavaratti
(“JRC Photovoltaic Geographical Information System (PVGIS) - European Commission,” 2021.) From January to April the solar irradiation is around 200kWh/m2. But it will decrease up to 100kWh/m2 in June and raises after September. This is because the months May to July experience monsoon in Lakshadweep and the sunlight will be the least. With the help of PVGIS the hourly data of solar irradiance at optimum angle is taken for the year 2016 and used for simulation in Matlab software. This remained the base for the calculation of required solar cells and the capacity installation.
4.4 Electrolyzer
Producing Green hydrogen may be done in a number of ways, but electrolyzers are the most environmentally friendly. As a result, more electrolyzers are being built and more testing on new models is being done in order to achieve a more energy efficient hydrogen output.
The alkaline electrolysis process was chosen in Kavaratti because of its cost-effectiveness and the fact that it is a well-established technique.
Alkaline is the most commercially used technology and have been used in commercial purposes since the early 1900s. Alkaline is a low-temperature technique, which operates at a temperature of 40-90ºC. It has a long lifetime of 20-30 years, or 60 000-100 000 hours.
Alkaline produces hydrogen with high purity, above 99.8%. The materials within Alkaline electrolysis can vary depending on model and purpose. The most commonly used electrolyte is sodium hydroxide or potassium hydroxide. Commonly used electrode materials are Raney nickel together with Sulphur addition or steel coated with nickel. The membrane is often polyphenylene sulfide (Ryton), polysulfone bonded (Zirfon) or anion-selective polymers. The
conversion from water to hydrogen and oxygen in a basic Alkaline electrolysis occur by following reactions
Anode: 2𝑂𝐻− → 1 2 𝑂2 (𝑔) + 𝐻2𝑂 + 2𝑒 – Cathode: 2𝐻2𝑂(𝑙) + 2𝑒 − → 𝐻2 (𝑔) + 2𝑂𝐻−
Hydrogen will be stored in the storage tank oxygen will be biproduct
4.5 Storage Tank
First, consider the terrain of the Kavaratti island when designing storage choices and sizes;
geological storage cannot be considered. As a result, the following storage solutions, such as liquified hydrogen and material-based storage systems, are relatively costly. This project cannot be completed in a cost-effective manner.
Finally, we chose compressed hydrogen storage technology as our preferred method of storing hydrogen in kavaratti. It is less expensive in hydrogen storage, and compressed storage is the most mature hydrogen storage technologyThe storage technology has been determined. The next move is to determine the optimal volume of storage, and one of the problems ahead is that increasing storage tank size would increase capital costs. The average daily demand of energy in Kavaratti has been analyzed in order to solve the problem.
4.6 Fuel cell
Fuelcell is the heart of this project. Fuel cells have a number of advantages over traditional combustion-based systems installed in kavaratti and are widely used in a number of power plants in the world especially in Korea, Japan and U.S and motor cars. Fuel cells have greater efficiencies than combustion engines and can transform the chemical energy in the fuel to electrical energy at up to 60% efficiency. Compared to combustion engines, fuel cells emit less pollutants. At the point of action, hydrogen fuel cells emit only water, meaning there are no carbon dioxide emissions or atmospheric pollution that cause smog or health problems.
Furthermore, since fuel cells have less moving parts, they are silent while in use. In Kavaratti, considered at a standard fuel cell that can produce 500 kW of electricity. According to the daily load.
