Muhammad Shidqy Wasis

Biodata

Name:

Muhammad Shidqy Wasis

Student Number (NPM):

2106727935

Born:

2 September 2004 (18 years)

Bandung, Indonesia

Major:

Mechanical Engineering (class of 2021)

 

Assignment 1: Design and Optimization of Compressed Hydrogen Storage

Compressed Hydrogen Tank Scheme (source: energy.gov)

Compressed Hydrogen Definitions

Compressed hydrogen storage refers to the method of storing hydrogen gas by compressing it to high pressures and storing it in specially designed containers or tanks. The process involves increasing the pressure of hydrogen gas, typically to levels between 350 and 700 bar (5,000 to 10,000 pounds per square inch, or psi), in order to achieve a higher density and maximize the amount of hydrogen that can be stored within a given volume.

Compressed hydrogen storage offers a practical and established solution for storing hydrogen in various applications, including hydrogen fuel cell vehicles, stationary energy storage, and industrial processes. It provides advantages such as high energy density, quick refueling times, and a reliable and well-established technology. However, it also poses challenges related to the storage pressure, safety considerations, and energy losses during compression.

 

Specification of Compressed Hydrogen Tank

Volume: 1 liter

Pressure rate: 8 bar (800 kPa)

Production cost: IDR 500.000

Objectives: Minimize surface area and material thickness that can withstand an 8 bar pressure

Design variables: Geometry and material selection (included thickness and strength aspect)

 

Factors and Processes Involved in Designing Compressed Hydrogen Tank

Designing and optimizing hydrogen storage involves considering various factors and processes to ensure safe and efficient storage of hydrogen. Here are some key considerations:

1. Storage Method: There are different methods for storing hydrogen, including compressed gas, liquid hydrogen, and solid-state storage. Each method has its own advantages and challenges, and the choice depends on factors such as energy density, safety, and cost.

2. Energy Density: The energy density of the storage system determines the amount of hydrogen that can be stored per unit volume or mass. Higher energy density enables greater storage capacity and longer operating range. Designing storage systems with high energy density is crucial for practical applications.

3. Safety: Hydrogen is highly flammable and requires careful handling and storage to ensure safety. Designing storage systems with appropriate safety measures, such as leak detection, pressure relief mechanisms, and robust materials, is essential to mitigate the risks associated with hydrogen.

4. Efficiency: Optimizing hydrogen storage involves maximizing the efficiency of the storage system. This includes minimizing energy losses during storage and retrieval, as well as minimizing any leakage or degradation of stored hydrogen over time. Efficient storage systems help reduce overall energy consumption and increase the viability of hydrogen as an energy carrier.

5. Materials Selection: The choice of materials used in storage systems is crucial. They need to be compatible with hydrogen, have high strength, and exhibit low permeability to prevent hydrogen leakage. Research and development efforts focus on developing advanced materials, such as carbon fibers, metal hydrides, and porous materials, to enhance storage capabilities.

6. Temperature and Pressure Management: Hydrogen storage often involves managing temperature and pressure conditions. Depending on the storage method, maintaining the appropriate temperature and pressure ranges can impact the performance, safety, and longevity of the storage system.

7. System Integration: Designing and optimizing hydrogen storage also involves considering the integration of storage systems with other components, such as hydrogen production, transportation, and utilization. Ensuring compatibility and efficiency among different system components is crucial for overall system performance.

8. Cost: The cost of hydrogen storage is a significant factor in its widespread adoption. Designing storage systems that are cost-effective and scalable is essential for the commercial viability of hydrogen as an energy carrier. Research and technological advancements aim to reduce the costs associated with materials, manufacturing, and infrastructure required for hydrogen storage.

9. Environmental Impact: Evaluating the environmental impact of hydrogen storage systems is important. This includes considering the energy requirements for manufacturing and maintaining the storage systems, as well as any potential emissions or waste generated during the process.

10. Regulatory Compliance: Designing hydrogen storage systems must adhere to relevant safety standards and regulations. Compliance with codes and regulations ensures the safe operation and deployment of hydrogen storage technologies.

Optimizing hydrogen storage involves a multidisciplinary approach, combining engineering, materials science, safety considerations, and system integration to develop efficient, safe, and economically viable storage solutions. Ongoing research and technological advancements continue to enhance the performance and viability of hydrogen storage systems.

Optimasi Penyimpanan

Ada beberapa tahapan dalam mendesain dan mengoptimasi sistem penyimpanan, dari yang sudah ada menjadi yang sesuai dengan batasan maksimal yang diinginkan.

1. Tentukan ukuran pelat yang akan digunakan berdasarkan volume yang dibutuhkan, yaitu 1 liter, namun menggunakan luas pelat seminimal mungkin menggunakan perhitungan sebagai berikut:

import math
from scipy.optimize import minimize

def objective(x):
    radius, height = x
    return 2 * math.pi * radius**2 + 2 * math.pi * radius * height

def constraint(x):
    radius, height = x
    return math.pi * radius**2 * height - 1000

initial_guess = [1, 10]  # Initial guess for the radius and height

# Define the bounds for the radius and height
bounds = [(0, None), (0, None)]

# Define the volume constraint
volume_constraint = {'type': 'eq', 'fun': constraint}

# Minimize the surface area subject to the volume constraint
result = minimize(objective, initial_guess, method='SLSQP', bounds=bounds,                                                                         
constraints=volume_constraint)
  
optimal_radius = result.x[0]
optimal_height = result.x[1]
min_surface_area = result.fun

print(f"\n\nOptimal Radius: {optimal_radius} cm")
print(f"Optimal Height: {optimal_height} cm")
print(f"Minimum Surface Area: {min_surface_area} cm²\n\n")

Dari perhitungan tersebut, didapatkan beberapa nilai ukuran berikut ini,
● Optimal Radius: 5.419261255088046 cm
● Optimal Height: 10.838519182022262 cm
● Minimum Surface Area: 553.5810443894838 cm²

2. Selanjutnya, dilakukan perhitungan dengan variabel budget yang telah ditetapkan, yaitu Rp. 500.000. Untuk perhitungannya, digunakan perhitungan sebagai berikut menggunakan python:

from scipy.optimize import minimize

# Harga dan kapasitas yang dibutuhkan
harga_per_unit = 500000  # Rupiah
kapasitas_per_unit = 1  # Liter

# Anggaran maksimal
anggaran_maksimal = 500000

# Fungsi Akhir
def fungsi_akhir(x):
    return -x * kapasitas_per_unit

# Kendala yang terjadi
def kendala(anggaran):
    return anggaran_maksimal - (harga_per_unit * anggaran)

kendala_anggaran = {'type': 'ineq', 'fun': kendala}

# Nilai awal
x0 = 0

# Batasan
batas = [(0, None)]

# Menyelesaikan masalah optimisasi
solusi = minimize(fungsi_akhir, x0, method='SLSQP', bounds=batas, constraints=[kendala_anggaran])

# Menampilkan hasil
print("Status:", solusi.success and "Biaya Optimal" or "Tidak ditemukan solusi")
print("Jumlah unit yang bisa dibeli:", solusi.x[0])
print("Total kapasitas penyimpanan yang didapat:", solusi.x[0] * kapasitas_per_unit, "liter")
print("Total anggaran:", solusi.x[0] * harga_per_unit, "Rupiah")

Hasil yang didapatkan adalah:
● Status: Biaya Optimal
● Jumlah unit yang bisa dibeli: 1
● Total kapasitas penyimpanan yang didapat: 1.0 liter
● Total anggaran: 500000.0 Rupiah

Menggunakan perhitungan di atas, bisa dilakukan plot terhadap perbandingan kapasitas dan jumlah yang didapatkan dengan code berikut:

# list grafik
unit_list = []
total_kapasitas_list = []