Cost Effectiveness Machines and Components-EEET3050

Preview text

1
Topic
Institutio n Affilia tio n
Name of student
Submissio n date
Module Title
2
Re ne wable Ene rgy Syste ms
Q1
Solution
Length from forebay = 5.1 m
2 jets @ 5 cm diameter
Jet velocity = 10m/s
Dynamics of power developed by Pelton is given by
dq/dt = h0 -h-hi)g A/L
Area = d = x5 = 15.708 cm 2
Specific velocity Ns = N(P) ½ / (H 5/4 )
= 12 (118 ½)/25 5/4 l
= 33.2 rpm.
Power generated is given by
= mhg = qV x gh
0.6 x 1000 x 5.1
= 30 60 W =3.06 kW.
b.)
solution
head h = 20 m
p = 60 kW
load factor = 100%
effic ie nc y of 85%
P = mgh/t
3
= qgh x v
P0 = effic ie nc y x power = 60 x 100/85
= 70.588
V = P/qgh
= 70.588 x 10 3/(1000 x2 0 x 9.81)
Flow rate = 0.3598 m/s
Q2
With the increased innovatio n and technolo gica l advancements in wind power generatio n,
there has been an equivale nt significa nt development in the wind power generatio n capacity
globally. Wind energy is among the clean energy sources that are approved to b e environme nta l ly
friend ly and sustainab le source since it has GHC emissio ns to the environme nt [4] . The increase d
commissio ning and installatio n of many wind power plants is attributed to the increased outp ut
effic ie nc y, sustainab ility of the systems and cost -effective ness machines and components used in
wind power plants. Wind generators are essential instrume nts or component of a wind power pla nt
system as they kinetic energy of the wind captured by wind turbines into useful electrical energy
[1] . There different types of wind generators used in wind power plants for the conversio n of the
kinetic wind energy into electricity. Some of the wind generators used are Synchronous generato r,
Squirrel -cage inductio n generator , and double -fed inductio n generator, among other types.
However, the type used in particula r plant depends on its conversion effic ie nc y, reliability and the
compactness of the generator design, all these factors affect the quality and quantity of the outp ut
power.
4
Among these types, Synchronous wind generator type is the most or commonly used in
wind power generation plants. Analysing the market demand for different types of generators,
synchrono us generators are the market leader for the last decade due to the high er rated outp ut
power as well as economica l feasibility [2] . The design of the modern synchrono us generators is
a state -of-the -art with competitive advantages in wind energy conversion compared to othe r
designs. Synchronous generators are widely used beca use they accommodate variable speed wind
turbines applicatio ns and their ability to generate power at grid frequencies due to low rotatio na l
synchrono us speeds [4] . They are cost effective because they donâ€t require pitch contro l
mechanism that often incre ase the cost of the turbines and more stress on the generator and
turbines. Unlike other generator types, the output generated power can be controlled through the
use of AVR for excitatio n of the field voltage.
Q3
Distribute d ge ne ration – It refers to th e electrica l power generatio n and storage achieved by serie s
of small interconnec ted generators, grid -connected and distributed through distributed energy
resources (DER). In other words, distributed generatio n is the applicatio n of differe nt technolo g ie s
to produce electricity at or near site for its consumptio ns. It involves a hybrid of power generatio ns
systems such as combined heat and power, wind turbines and solar panels [1] . Itâ€s the science of
combining the small -sca le energy sources and generate el ectric ity close or at the point of its
utilizatio n and the technique is famously associated with renewable and modular energy
generators.
List of Distributed Generation Systems
i. Solar photovolta ic panels
ii. Combined heat and power systems
5
iii. Municipa l solid w ater incineratio n
iv. Natural -gas -fired fuel cells
v. Fuel cells powered by natural gas
vi. Biomass cofiring
Application of Microturbines in Distributed Generation
Microturbine s in distributio n generatio n is relative ly new technology largely used for
stationary energy applicatio ns with numerous power distributio n advantages compared to othe r
small -sca le power generatio n .
Microturbine s are widely used in stand -by power cogenera tio n systems to ensure relia b ly
power supply for consumers
Microturbine s are also used to achieve power quality and peak shaving in power genera tio n
plants
They are also used in landfill gas applicatio ns and resource recovery systems since the y
are developed to use variety of fuels
Microturbine s are used in power generation (conversio n of k inetic energy in wind into
electric ity) for small commercia l build ings like motels, restaurants, offices, hotels and retail stress
among others.
There is progress on the development of microturb ines for the transport applicatio ns with
several automotive p layers expressing interest on microturb ine technology for hybrid cars due to
fuel -consumptio n effic ie nc y and lightwe ight benefits.
Q4
Solution
6
Referring Kyocera rating, KC120 is a 120 -W module with a minimum power point at a volta ge
and current of 16.9 V and 7.1 A. respectively
Given that December is the worst solar month with a peak of 3.1 hours of sunlight at a tilt of L+15
Therefore 1 string of module is delivered in December is estimated as
Ah to invertor = current x peak hour/day x Coulomb ef fic ie nc y x de -rating factor
= 7.1 x 3.1 x 90% x 0.90
= 17.83 Ah/day per string.
For 85% effic ie nc y invertor to deliver the given 3000 Wh/day of 120 V ac it requires a 24 -V dc
input of;
Invertor Input (dc) = 3000/(24 x 0.85)
= 147 Ah/day at 24 V
But since the given modules has a rating voltage o f 16.9 V, it is assumed to be a â€12 -V modulesâ€
Hence 2 modules in series are required to produce 1 24 -V string.
No of l strings needed in parallel
= 147Ah/day/ 17.83Ah/day -string
= 8.25 strings
Suppose the system is undersized slightly and use 8 stings in parallel with 2 modules per string for
16 modules
Considering the de -rating factor of 0.90, the n PV output will be;
PV = Current/string x peak x factor (de -rating)x String numbers
= 7.1 x 3.1 x 0.90 x 8
= 158 Ah/day @ 24 V dc.
The battery with 90% Coulomb effic ie nc y will give
7
Battery Output = PV output x Coulomb efficie nc y
= 158 x 90%
= 142 Ah/day @ 24 V dc.
And the 85% invertor will deliver
Invertor Output = Battery Output x 24 V x effic ie nc y
= 142 x 24 x 85%
= 2900 Wh/day @ 120 V ac.
So, the design is slightly shy of the intended goal of 3000 Wh/day. The system diagram design of
the PV system is as shown
Q5
Hydroge n Ene rgy syste ms
Hydrogen energy systems are considered as potential solutio n to constantly increa sin g
demands for clean energy systems. Despite being proven to be an alternative clean energy source,
the exploratio n of hydrogen -based energy has been at the minimum due to l ack of effec tive
technology to help in harnessing hydrogen energy for industria l applicatio ns [2] . Safety in
8
production or generatio n of the hydrogen -based energy has also been another factor limiting the
wide scale harnessing of hydrogen -based energy. In the past few years (five years) innovatio n and
technology advancement has led to the discovery and developme nt of various hydrogen harnessin g
techniques that have significa ntly boosted the utiliza tio n of hydrogen energy systems [6] . The two
most significa nt techniques are
Steam -Methane Reforming
This is the mostly used hydrogen production technique for commercia l hydrogen productio ns .
Currently, steam -metha ne reforming hydrogen production techniq ue accounts for nearly 89% of
the c ommercia lly produced hydrogen energy in the USA, UK and Germany [2] . Commerc ia l
petroleum refinerie s and commercia l hydrogen producers utilizes steam -metha ne reforming to
disinte gra te (separate) carbon atoms from hydrogen atoms in methane (CH 4). In this hy dro ge n
harnessing, steam at higher temperatures (between 1350 oF to 1850 oF) and a pressure rangin g
between 4 bar and 25 bar is reacted with methane . For this reaction to occur there has to be a
catalysis to spice the reaction and produce hydrogen gas, negli gib le amount of carbon dioxide and
carbon monoxide [3]
Electrolysis
Electrolysis is another hydrogen production technique that has contributed or boosted the wide use
of hydrogen energy systems. the process involve s splitting of hydrogen atoms from water mole c ule
through use of electric current. On large scale production of hydrogen, the process is often referre d
to as power -to-gas process where electric current is used to produce hydrogen gas. Electroly s is
techniques offers solutio n to the safety challen ges that has derailed and limited the large -sc a le
production of hydrogen as it doesnâ€t produce any emissio n or byproduct besides oxygen and
9
hydrogen [4] . Another advantage of the electrolysis production of hydrogen is that the power for
the production can be sourced from any renewable energy sources or nuclear energy source
Pyrolysis
Pyrolysis or copyrolysis is another promising technique in the large -scale production of hydro ge n
from raw organic materia ls. in this process the raw organic substances belie ved to have hydro ge n
content are heated and the gasified at a pressure of about 0.6MPa in temperature range of 600 oC
to 900 oC [5] . The entire process is conducted in the absence of air and oxygen thus ruling out the
release or emissio n of carbon dioxide . T hese are some of the hydrogens harvesting technique s tha t
has boosted the utilizatio n of hydrogen energy systems in the past few years.
Hydroge n Inte gration
Besides providing clean electrica l energy to power plants, power household systems and ligh t in g
systems, the eliminatio n of fossil -based fuels requires an alternative gas supply systems to replac e
the fossil -based gases used in other applicatio n like cooking, welding operations among othe r
applicatio n. Hydrogen stands a potential replacement of the f ossil -based gases used in welding and
cooking applicatio n, but for centuries, the production of the adequate hydrogen gas to replace these
fossil gases has been the greatest limitatio n for achieving sustainab ility in the gas sector [4] .
Luckily, with the d iscovery of advanced hydrogen harnessing technologies such as pyrolysis,
electrolysis, biogas gasifica tio n, desulfuratio n and autotherma l reforming among other mode rn
technologies have enhance the integratio n of hydrogen gas systems into the distributio n g rid
networks
Q6
Calculations
Solution
10
Fuel cell stuck generate = 48 V dc
Cell operating at 0.6 V @
Voltage output for cell, V = 0.85 -0.25J
= 0.85 – (0.25/A)J
Where;
A is the cell area I is the current in amps J is the current density
Now
P = 1kW V = 48 V Vz = 0.6
Finding the number of stock cells N
N = V/Vz = 48 /0.6
= 80 cells
Hence 80 cells would be required to generate 48 V dc.
ii. Membrane Area
Current needed through each cell I = P/V
I = P/V = (1000/80 cells) /(0.6/cell)
= 100/(80 x 0.6)
= 20.83 A
Mass of H2 consumed (k g/h)
= I x 3.759 x 10 -3
And flow rate of H2 = I x 3.759 x 10 -3/ 1.1
= (20.83 x 3.759 x 10 -3)/ 1.1
= 71.18 x10 -3 kg/h
11
Bibliography
[1] A. R. Nejad et al. , “Wind turbine drivetra ins: state -of-the -art technologies and future
development trends,” Wind Energy Science , vol. 7, no. 1, pp. 387 –411, Feb. 2022, do i:
10.5194/wes -7-387 -2022.
[2] Y. Peng, W. Qiao, F. Cheng, and L. Qu, “Wind Turbine Drivetrain Gearbox Fault Diagno s is
Using Inform atio n Fusion on Vibration and Current Signals, ” IEEE Transactions on
Instrumentation and Measurement , vol. 70, pp. 1 –11, 2021, doi: 10.1109/TIM.2021.3083891.
[3] H. A. Muqeet et al. , “Sustainab le Solutions for Advanced Energy Management System of
Campus Mi crogrids: Model Opportunities and Future Challenges, ” Sensors , vol. 22, no. 6, p. 2345,
Jan. 2022, doi: 10.3390/s22062345.
[4] J. Brian, “Doria Marciuš,” scholar.google.com , 2022.
https://sc ho la r. goo gle.co m/c ita tio ns? user=e GnXSC0AAAAJ&hl=e n&o i=sra (accesse d May 15,
2022).
[5] P. Puranen, A. Kosonen, and J. Ahola, “Technica l feasibility evaluatio n of a solar PV based
off -grid domestic energy system with battery and hydrogen energy storage in northern climate s, ”
Solar Energy , vol. 213, no. 7, pp. 246 –259, Jan. 2021, doi: 10.1016/j.solener.2020.10.089.
[6] M. Daneshvar, B. Mohammad i -Iva tloo, K. Zare, and S. Asadi, “Transactive energy
manageme nt for optimal scheduling of interconnec ted microgrids with hydrogen energy storage , ”
International Journal of Hydrogen Energy , vol. 46, no. 30, pp. 16267 –16278, Apr. 2021, do i:
10.1016/j.ijhyde ne.2020.09.064.