Open Access Research Article
Journal of Fundamentals of
Renewable Energy and Applications
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ISSN: 2090-4541
J Fundam Renewable Energy Appl, an open access journal
ISSN: 2090-4541
Cowen et al., J Fundam Renewable Energy Appl 2019, 9:2
Volume 9 • Issue 2 • 1000277
*Corresponding author: Torrey Wagner, Air Force Institute of Technology,
Systems Engineering and Management, Wright-Patterson Air Force Base, OH,
USA, Tel: +1 937-255-6565; E-mail: torrey.wagner@aft.edu
Received August 06, 2019; Accepted August 23, 2019; Published August 30,
2019
Citation: Cowen L, Wagner T, Dudis D, (2019) Austere Location Wind Turbine
Energy System Analysis. J Fundam Renewable Energy Appl 9: 277.
Copyright: © 2019 Cowen L, et al. This is an open-access article distributed under
the terms of the Creative Commons Attribution License, which permits unrestricted
use, distribution, and reproduction in any medium, provided the original author and
source are credited.
Abstract
One promising technology to combat an energy shortage in austere locations is wind energy. In combination with
battery storage and generator backup, we explore the feasibility of using a hybrid energy system to reduce the volume
of diesel fuel required. Modeling the energy demands in austere locations will enable missions in remote settings to
optimize their energy costs, increased their energy resiliency and assure their supply. For a modeled time-series energy
requirement that varied between 2.4 MW and 5.1 MW, the optimal wind system size was 9.9 MW of installed wind power
paired with a 741 kWh battery. Assuming an elevated price of fuel, the cost of operating the base with only fuel was
greater than $55 million dollars. The total component and operational cost of the optimized wind, generator and battery
system was cost-effective within one year and totaled $48 million dollars.
Austere Location Wind Turbine Energy System Analysis
Lukas Cowen, Torrey Wagner* ans Douglas Dudis
Air Force Institute of Technology, Systems Engineering and Management, Wright-Patterson Air Force Base, OH, USA
Keywords: Energy resilience; Energy efciency; Renewable energy;
Wind energy
Introduction
Remote locations require power for communications, security,
operational use, and the inhabitant’s quality of life; however a large
portion of that power is currently generated through liquid fuels,
which require overland transport or airlif. Wind turbines may increase
the energy resiliency of a location by reducing logistical demand of
frequent liquid fuels deliveries.
Te Department of Defense stands to beneft from the
implementation of wind turbines due to the costs of transporting liquid
fuel. Tis could prevent ground casualties during convoy operations,
which account for approximately nine percent of Army casualties in a
deployed environment [1].
Literature Review
In general, a successful transition to renewable energy will require
addressing several challenges in areas of energy resilience, technology,
and corporate culture [2-6]. Specifc to this work, factors related to
wind as a resource, energy requirements and lifecycle considerations
of implementing wind turbines at an austere location will be discussed.
Wind resource
Wind energy is derived from an uneven distribution of solar energy
and was frst harnessed via wind turbine to generate electricity by
James Blyth of Scotland in 1887 [7]. In general, wind turbine systems
are composed of a rotor, generator, tower, and control equipment [8].
Te rotor converts wind energy into rotational energy. Tis rotational
energy is directed to the generator which produces electricity, the
tower provides structural support for the rotor and generator, and the
control equipment optimizes the operation, power output, and safety
of the system. Te minimum air speed required to generate power is
called cut-of power. As wind speed increases, the power generated by
the turbine increases, and generation ceases to protect the system from
damage when the wind becomes too powerful.
Wind resource data for a hypothetical location in East Asia is
analyzed in this work, and the wind intensity data fts a Weibull
distribution marked as a grey curve in Figure 1 [9]. Most wind resource
data can be modeled through the Weibull distribution, given as:
1
(; , )
k
k x
fx k λ
λ λ
−
=
k x
e
λ
−
(1)
In the equation above, k is a shape parameter greater than zero, and
λ is the scale parameter of the distribution. Te data fts the Weibull
distribution with λ = 5.15 and k = 1.88. Te mean speed was 4.56 m/s.
Tis is reasonable since because both in the Weibull distribution and
wind data, values less than the mean are more common than extreme
values including wind gusts.
Energy requirement
Energy requirements vary with the size, location, and operations
of the base. Although it is useful to consider the average daily energy
use of a deployed location, peak loads are important to consider when
designing a power system. Tis analysis will utilize wind and electrical
demand data modeled for a hypothetical outpost by McCaskey [10].
Figure 2 shows the seasonal variation of energy demand and will
be used in conjunction with the base’s annual wind data to calculate
the optimal number of wind turbines to meet the energy requirement.
Te electricity demand showed daily and seasonal variation. Summer
afernoons exhibited the most intense demands, and the evenings
required the lowest electrical load.
24
18
12
6
0
Feb Apr Jun Aug Oct Dec
kW
5,100
4,560
4,020
3,480
2,940
2,400
DMap
Hour of Day
Figure 1: Modeled annual electrical demand by hour.