1. Acknowledgments
We would like to thank Mark Legacy from
Humpback Hydro passing this project along
to the UBC Capstone program and giving
us the opportunity to work on this project.
We would also like to thank our faculty
supervisor Dr. Joshua Brinkerhoff for
taking the time to support us through the
Capstone project.
Introduction
The purpose of this project is to complete
proof of concept design of Humpback Hydro’s
patented Ocean Hydro Energy Storage System.
A conventional Pumped Storage Hydro system
uses two reservoirs to store energy. The top
reservoir is land locked and requires a high
elevation, while the bottom reservoir is either a
lake or an ocean. During peak energy demand,
water is run from the high reservoir to the low
reservoir through a turbine to generate
electrical power through a hydro turbine.
During low energy demand, the upper
reservoir is replenished. The Humpback Hydro
system takes this conventional Hydro Energy
storage principle found on shore and places it
in an offshore environment.
There are four main deliverables for this
project which includes determining the system
efficiency, developing a computer program to
aid in sizing these facilities, selecting power
generation equipment and completing CAD
modelling of the system.
Design Requirements
System Analysis
The system was analyzed to estimate the
efficiency of the system and the amount of
concrete required. This analysis also indicated
reservoir volumes, penstock and pipe
diameters, power requirements, required head,
and flow rates.
The efficiency of the system was analyzed
by modelling the system and including the
efficiencies of the turbomachinery [2] and
accounting for head losses. Figure 2 below
shows the efficiency for various combinations
of head ratio (HR) which is the upper turbine
head divided by lower turbine head.
Conclusions
All objectives were met with the following
deliverables:
1) Determined that a 10 MW facility, with 3
hours of storage time, and 6 hours to
replenish the upper reservoir, can achieve
an efficiency of 70.2% and requires
220,000 cubic meters of concrete.
2) Developed a MATLAB Graphical User
Interface which enables the user to input
required power, storage time, and low
demand duration to calculate efficiency,
concrete amount, flow rates, penstock
sizes, and required head.
3) Selected power transmission equipment
including a TMEIC 4 Pole Generator and a
three phase HPS transformer.
4) Completed CAD modelling of the system
including an animation illustrating the
operating principles of the Ocean Hydro
Energy Storage System.
Ocean Hydro Energy Storage System
Shariq Codabux, Mitchell Lamoureux, David Martens, Billy Su
Faculty Advisor: Joshua Brinkerhoff, Industry Collaborator: Humpback Hydro
Group #8
References
[1] M. A. Herzog, Practical dam analysis,
London: Thomas Telford Publishing,
1999.
[2] S. L. Dixon and C. A. Hall, Fluid
Mechanics and Thermodynamics of
Turbomachinery, Oxford: Elsevier, 2010.
[3] T. M. E. I. C. CORPORATION,
"http://www.tmeic.com/Repository/Other
s/4P%20TG.pdf," [Online].
[4] H. P. Systems, "Dry-Type Medium
Voltage Distribution [Power]
Transformer," Hammond Power Solutions
Inc. , 2014.
[5] Humpback Hydro, "Humpback Hydro
Inc, Grid Scale Energy Storage
Technology," Vancouver, 2014.
For further information
For further information contact Mitchell
Lamoureux Mitchell.Lamoureux@gmail.com
Fig. 1. Schematic showing
operation of the Ocean Hydro
Energy Storage System [5]
Design Description
The Humpback Hydro System as shown in
Figure 1 operates using the following
processes:
•
1-2 Water is run through the lower turbine
generating power
•
2-3 Water is pumped to the upper reservoir
•
3-1 Water is released through the upper
turbine again generating power
Processes 1-2 and 3-1 occur
simultaneously during peak electricity demand
and process 2-3 will occur during low demand.
Fig. 2. Efficiency of 10 MW System for
Various Combinations of Head Ratios
Electrical
The power transmission set includes a
generator and a power transformer to meet
local power grid standards. This set consists
of a generator and transformer as described in
Table 3.
Graphical User Interface
The design of the Ocean Energy Storage System
will vary depending on the end user requirements. A
graphical user interface (GUI) was developed using
MATLAB to aid in the sizing of the system (Figure
3). The GUI performs calculations to size penstocks,
piping, reservoir volume, and heights of the system.
It optimizes the system based on the highest
efficiency and minimal concrete when provided with
the following inputs from the user:
•
Required Power
•
Storage Time
•
Low Demand Duration
CAD Modelling/FEA
Solid modelling was completed using the values
from Table 2. This system will have a provide
10MW of power over three hours, and replenish the
upper reservoir in six hours.
Using these values, the system was modelled
using Autodesk Inventor. Figure 4 shows a cross
section of the system showing the components of the
system. The components in green include the lower
penstock, generator, and turbine. the blue shows the
pumping and piping system, and the red shows the
lower penstock and generator.
Fig. 3. Graphical User Interface 1) User
Inputs 2) Push Button To Calculate 3) GUI
Outputs
The gravity dam surrounding the system is
designed to withstand the hydrostatic and
dead loads acting upon it. Specifically, the
dam is designed to have:
•
Safety Factor in Compression > 3
•
Safety Factor Against Sliding > 1.5
•
0 tensile stresses [1]
Table 2 list the parameters calculated
for a plant generating 10 MW, storage time of
3 hours, and replenishing the upper reservoir
in 6 hours. This system was the most efficient
with the least amount of concrete from the
analysis.
Requirements
• Dam shall be designed to withstand the
hydrostatic and dead loads acting on the
structure
• Structure/Components will withstand the
corrosive nature and extreme weather
conditions of the ocean.
• Power will output as 50 or 60 Hz AC as
specified by regional power requirements
• The design should address the life cycle of
the plant to be 65-80 years
• The design should allow for maintenance to
the electrical/mechanical components
• The selected facility will sustain 10 MW of
power over 3 hours, and replenish the upper
reservoir in 6 hours.
Table 2. Calculated Parameters for the
10 MW Ocean Hydro Storage System
Parameter Value
Lower Turbine Power Output 2.86 MW
Lower Turbine Head 20 m
Lower Penstock Diameter 1.6 m
Lower Reservoir Volume 170,000
Upper Turbine Power Output 7.14 MW
Upper Turbine Head 50 m
Upper Penstock Diameter 1.6 m
Upper Reservoir Volume 170,000
Pump Flow Rate 7.9 /s
Pump Power 7.12 MW
Total Amount of Concrete 220,000
Total System Efficiency 70.2%
Parameter Value
Lower Turbine Power Output 2.86 MW
Lower Turbine Head 20 m
Lower Penstock Diameter 1.6 m
Lower Reservoir Volume
Upper Turbine Power Output 7.14 MW
Upper Turbine Head 50 m
Upper Penstock Diameter 1.6 m
Upper Reservoir Volume
Pump Flow Rate
Pump Power 7.12 MW
Total Amount of Concrete
Total System Efficiency 70.2%
Table 1. List of Design Requirements
Using the CAD model a finite element analysis (FEA)
stress analysis was completed. The FEA examined the
stresses in a full upper reservoir, to indicate the
maximum stresses and minimum safety factors obtained
in the structure. Figure 5a below shows the safety factor
of the structure, while Figure 5b shows the von misses
stress in the structure.
Fig. 4. System Overview showing all
components
Fig. 5. Stress simulation of fluid acting on
the upper reservoir a) Safety Factor b) Von
Mises Stress
Component Description
4 Pole
Generator
• The required generator must be
rated for 1-10 MW, with a
frequency of 60 Hz
• A TMEIC 4 Pole generator is a
viable option [3]
Power
Transformer
• The transformer must have the
same frequency, power rating, and
input voltage as the generator
• A three phase HPS Dry Type
transformer is a viable option [4]
Table 3. Electrical Components and their
descriptions
1
2
3
Efficiency vs. Lower Turbine Head
a) b)