Victoria Shue
Professor Warren Powell
Optimizing Wind Portfolios: From
Production Through Consumption
Abstract: Given the limitations of wind energy (production volatility), energy
storage (location and capacity), and grid transmission (load balancing), we will
arrive at a portfolio that optimizes these 3 factors, so as to minimize energy lost in
the process of moving from production to consumption.
Chapter 1: Introduction
In recognition of the large-scale and undesirable effects that manmade CO2 has on
climate change, there has been a strong global push to replace fossil fuels with
renewable energies that leave little to no carbon footprints. Currently, hydroelectric
power forms the great bulk of those renewable energies that are already in use. On
the other hand, wind is fast coming onboard as another viable sustainable energy
option, due to its relatively developed technology. The problem with wind, however,
is its volatility. Hence, one challenge is to reduce this volatility, so as to provide a
steadier, less volatile stream of electricity production.
Another challenge facing us is the storage of electricity. Electricity itself can only be
stored for short periods of time. On the other hand, wind tends to blow more
strongly and more frequently at night, which also happens to be when energy usage
tends to be at its lowest levels. In other words, electricity production cannot be
instantly coupled with electricity usage, and to prevent that nighttime electricity
production from going to waste, a variety of storage options must be utilized to
store the electricity until it is needed.
Into this mix, we will add one more challenge: that of the electrical grid. The
electrical grid is itself subject to load limits, and to form a more realistic model of
wind energy, from production to consumption, we should take these limitations into
account as well.
In sum, this thesis will have 3 prongs: wind, storage, and the electrical grid. Taking
into account the limitations on all 3 prongs, we hope to determine an optimal mix of
wind farms, storage options, and grid loads.
Chapter 2: Wind
Discussion of wind.
Victoria Shue
Professor Warren Powell
About Wind
A History of Wind Power
Wind power over the years: Humans have been harnessing the power of wind for
over 5,000 years, such as to propel ships and to ventilate homes. Windmills have
been in use for over a thousand years, to pump water for irrigation and to mill grain.
The modern wind power industry, as we know it, launched in 1979, with small (by
today’s standards) electricity production capacities of 20 – 30 kW per wind turbine.
How Wind Power Works
How wind is generated: The sun unevenly heats the Earth’s surface; the resulting
heat gradients then lead to wind.
Wind blowing spins turbines that are connected to a transformer, which generates
electricity. The technical details may get more nitty-gritty, dependent on how
relevant such a discussion would be to parts of the thesis.
Wind Production & Potential
How much wind power is currently generated in the USA. Where are the top windproducing regions, and how much do they generate. Are there some untapped
regions?
How much wind power is currently generated in the world. Where are the top
players, and how much do they generate.
The amount of wind that blows across the Central USA can theoretically generate
enough energy to supply all of the USA’s electricity demands.
Wind Economics
Is the technology advanced enough? Yes.
Is it economically feasible? With the right incentives.
Discuss current (government) incentives in place that make wind economically
viable. Will these incentives continue into the future? And if they don’t, can wind
still survive without them? In other words, could wind feasibly stand on its own two
feet without forever relying on government subsidies to prop it up?
Limitations
Location: Wind blows more strongly in some locations than others, frequently in
relatively uninhabited places. As a result, the resultant electrical production would
have to be transported via gridline to demand centers.
Noise: “Not in my backyard” argument.
Environmental: Birds are frequently killed on the blades of wind turbines.
Victoria Shue
Professor Warren Powell
Capacity: The amount of energy that a single turbine can generate is directly
dependent on the length of its blades, which themselves have a physical limit.
Hence, relatively speaking, the amount of energy that a single turbine can generate
is small, and so a wind farm must have an aggregate of many such turbines to
actually be economically viable.
Model
Preliminary model, taking into account (among other things): locations of wind
farms; production (amount) of electricity production at each wind farm, over time;
correlations of electricity production amongst wind farms; cost of electricity
production at a particular wind farm.
Chapter 3: Storage
Discussion of storage.
About Storage
Electricity, as a form, can only be stored for short periods of time. Hence, storage is a
necessity, so that unused electricity is not merely thrown away.
Storage Options
Discuss storage options, and their pros and cons. (The following list will be pared
down as I go through each one and determine which ones are actually currently
viable as well as already in place.)
Victoria Shue
Professor Warren Powell
Chemical
Hydrogen
Biofuels
Liquid Nitrogen
Oxyhydrogen
Hydrogen Peroxide
Biological
Starch
Glycogen
Electrochemical
Batteries
Flow Batteries
Fuel Cells
Electrical
Capacitor
Supercapacitor
Superconducting Magnetic Energy Storage (SMES)
Mechanical
Compressed Air Energy Storage (CAES)
Flywheel Energy Storage
Hydraulic Accumulator
Hydroelectric Energy Storage
Spring
Thermal
Ice Storage
Molten Salt
Victoria Shue
Professor Warren Powell
Cryogenic Liquid Air / Nitrogen
Seasonal Thermal Store
Solar Pond
Hot Bricks
Steam Accumulator
Fireless Locomotive
Fuel Conservation Storage
Model
Preliminary model, taking into account (among other things): locations of storage
options; capacity of each individual storage facility; amount of time that electricity
can be stored at site; cost of storing electricity at a particular site.
Chapter 4: Wind & Storage
Combining wind and storage.
Model
Combine our two preliminary models of wind and storage to get an initial optimal
mix of these two prongs.
Results
Discuss the results. Does this mix make sense? Are there any outcomes that we find
surprising, and if so, why is this outcome in fact better than what we had originally
thought?
Chapter 5: The Grid
Discussion of the grid.
About the Grid
Focus will be on the Eastern electrical grid network. Discuss the components of that
grid, and possible future plans for the grid.
Model
Preliminary model, taking into account (among other things): Eastern electrical grid
network – transmission lines (start points and end points), and their capacities, if
different; demand at any given time on the grid.
If demand at a given time on a single line is above that line’s capacity, then
electricity must be drawn from a different line, even though the electricity may be
drawn from farther away, and hence some energy will be lost in transmission.
Victoria Shue
Professor Warren Powell
Chapter 6: Wind, Storage, & The Grid
Combining wind, storage, and the grid.
Model
Combine all 3 prongs – wind, storage, and the grid – to get our desired optimal mix.
Results
Discuss the results. Does this mix make sense? Are there any outcomes that we find
surprising, and if so, why is this outcome in fact better than what we had originally
thought?
Compare
How does this mix differ from the mix sans the grid? Were these differences to be
expected? If not, discuss how they might possibly have come to be.
Chapter 7: Conclusion
Summarize the research, and discuss the conclusions reached. Indicate where
opportunities for further research lie.