The Optimal Hybrid Energy System in Australia

​Abstract

The project aims to discover and assess the optimal hybrid energy system that can be used in the remote and rural areas of Australia to provide electricity to Base Transceiver Stations. The focus was on discovering the sustainable approach to addressing the issue because of the necessity to decrease the dependence on diesel generators in remote areas and increase the use of renewable energy sources. Methodologies included the development of the BTS load profile for remote areas, the development of the sufficient power plan for the relevant load profile, simulations to assess the efficiency of the proposed approach, and the analysis of the wind-solar Hybrid Energy System for BTS with the use of the HOMER energy software and Matlab software. It was found that the use of the hybrid energy system for powering Base Transceiver Stations was a feasible approach to address the problem of proposing a sustainable strategy to powering stations in remote areas in Australia.

Introduction

The worldwide growth of BTS (base transceiver stations) is progressively proceeding in areas wherein the power supply network frequently breakdowns for a long duration of time or elsewhere access to the power supply network is not available. So as, to also make sure a power supply to Base Transceiver stations in such areas, diesel generators have fixed. Such need an extraordinary repairs effort plus use moderately diesel fuel in large quantity for very small level productions. Consequently, diesel generators acquire high working expenditures in addition to current workers of mobile telecommunications sites with the task of having to control their aggregate budget of tenure. Finding steadfast plus power solutions that are cost-effective for the global development of communications into agrarian and inaccessible regions show a very thought-provoking issue nowadays. Networks are also not accessible or their extension leads might be tremendously expensive in the inaccessible region. While early expenses are low, operating these locations with generators need substantial repairs, high consumption of fuel, and distribution expenses because of the trek in fuel rates. So, Renewable energy sources are alternative sources to power inaccessible base station locations.

Background of the Study

Current exploration and progress of renewable power sources have presented tremendous prospective using support to energy generation systems. So, by way of encountering continued payload requirements of BTS (base transceiver station) throughout fluctuating expected circumstances, diverse resources of energy, as well as converters, must be combined for protracted utilization of substitute electricity. Designed for Australian inaccessible site, one of the utmost another way of renewable energy sources for instance wind-solar Hybrid Energy System for BTS (base transceiver station). The usage of the standalone solar wind with a diesel hold-up system to give the power supply of inaccessible regions might provide commercially appealing alternate used for cellular telecommunication network above the usage of conventional diesel generators in coming years.

It provides the idea of the design of a hybrid energy system that creates by the combination of a wind turbine in addition to solar photovoltaic panels. Based on the accessibility of renewable energy sources also the power consumption of base transceiver stations, it is predetermined to execute an unconventional standalone Hybrid Energy System merging solar photo-voltaic panels, minor wind turbine-generator, and the latest power automated tools. In some previous years in the meantime of the early ’70s, the world is suffering higher costs of fuel that had produced numerous fuel crunches. As well, the world is suffering numerous ecological problems connected to the exploitation of remnant oil. Telecommunication industrial science is among one of the profligate rising industrial sciences for the period of these generations. The communication firms are constantly confronted to deliver continuous services to agrarian and an inaccessible region anywhere there is no consistent power supply of electricity is available.

So, renewable energy systems are turning out to be progressively famous in those trades to offer consistent power supply to inaccessible regions. Presently, in many situations, the communication stations utilize diesel generators attached with hold-up batteries to deliver power. Consequently, with the help of renewable energy sources communication firms are now trying to deliver a consistent power supply. Presently, to provide power generation also to improve productivity in addition to the working costs of this system renewable energy sources are used in the proposed system by a combination of photovoltaic panels and wind turbines. In this proposed project wind and Photovoltaic will be used as the central power causes aimed at the Base Transceiver System and conventional diesel generator and a battery array are also combined as a hold-up electricity supply (Fig. 1). The conventional diesel generator is served as an appliance to deliver longstanding electricity storing and the battery is utilized as a hold-up for temporary electricity storing.

The BTS System (on the left).
​Figure 1. The BTS System (on the left).

Aim

This project aims to produce power by also transmitting its mobile tower through additional power pleading transmission to town. The aim of the project is also to discover an optimal standalone hybrid energy system to provide electricity to a BTS (Base Transceiver Station) in remote areas so that its dependence on diesel generators becomes less. Moreover, the purpose of the project is to solve the problem of loss of signal and connectivity in rural regions due to the difficulty and cost of connecting a BTS to a power grid in regions. Therefore, by using a hybrid system consisting wind turbine that is integrated with solar photovoltaic panels telecommunication industry will be able to reduce the cost of on-grid connections, save time, and maintain a healthy environment. Another aim for this project is to be able to build a simulated design for powering a BTS that is feasible and applicable to most cases of BTS power connection in most rural areas around Australia.

Project Objectives

The key objective of the current study is the techno cost-effective optimization of the proposed hybrid system. The other objectives are as follows:

  • Decrease addiction to conventional causes of electricity.
  • Maintainable growth and decreasing carbon footmark of the firm.
  • Decrease Opex for mobile workers, also assistance spread agrarian inhabitants at lesser rates.
  • On the way to raise power efficiency of the firm, thus decreasing electricity rates.
  • Persist modest in the Telecommunication Substructure trades.

In this project, it is expected to design a simulated version of a BTS power supply that is reliable, sufficient, and sustainable. With the aid of MATLAB development software and HOMER energy software, it is expected to deliver a sufficient overview of the project in terms of feasibility and applicability of the project. The reasons to use two different software’s is that Matlab would only provide a technical solution and simulated demonstration but, it will not show any economic statistics nor any costs or feasibility reports however, Homer software will provide a clear approximation of initial costs, total profit and an accurate detailed feasibility report stating all economical inputs and outputs for this project.

Project Benefits and Implications

Also, there are two basic benefits to exploiting renewable energy resources intended for the situation of unconnected or hybrid power supply systems of Base Station locations. The first benefit examines a lessening or thorough removal of OPEX (mobile operator operational expenditure) straight linked to costly oil desired to drive conventional diesel generators. Similarly, gathering sources of renewable energy to provide electricity to Base station locations permits the domestic production of electricity, which causes the lessening of carbon dioxide release produced by conventional diesel generators.

This project has many technological, environmental, and economical benefits. In terms of technology powering BTS by a combination of both wind turbine generators and solar photovoltaic panels plus the addition of an emergency generator (in case of any malfunctioning in power resources) would enable the spread of BTS widely without any problems regarding grid connections and the infrastructure need to house such connections. Furthermore, may enhance the GSM (Global System for Mobile Communications) signal coverage in rural areas, which would provide a wider span of emergency signal coverage in emergencies. More to add, it is a sustainable way to provide sufficient power sources decreasing the pollution level associated with BTS connection to an on-grid network, hence saving the natural habitat of wild animals. Besides, using sustainable energy in powering BTS can reduce the cost of operation of telecommunication network therefore reducing the costs associated with using GSM by the user.

Literature Review

Review of Theories and Studies

Electricity usage and CO2 (carbon dioxide) releases have in recent times come to be the matter of superior attention to the industry of mobile. It is highlighted that BSs (base stations) are the big electricity demanding customers in the mobile systems of mobile workers [1]. However, new approaches to powering BSs need to be discussed in addition to traditional ones. The reason is that the stations using fuel produce not only harmful carbon dioxide, but they are also inefficient concerning energy production. Thus, only 30% of the fuel generated energy can be converted to electricity necessary for powering BSs when a high percentage of the energy is lost [3]. Moreover, the productivity of BSs powered with the help of diesel generators is often threatened because of failures and weaknesses in the work of these generators. Tina and Gagliano note that more than 60% of failures in the BSs’ work are associated with the problems in diesel generators and powering the station [4]. Therefore, throughout previous days, substantial consideration was provided by tools producers, mobile workers as well as scholars from academic circles to the results devoted to refining power energy efficacy of base stations in mobile networks. Intended for attaining this, few of the renowned methods are: power energy-effectual hardware or base station location plan, energetic controlling of the network means with slumber means then cell rising, a SON (self-organizing network) idea or consuming renewable energy resources to provide power supply to base station locations.

As an illustration of the consumption of power energy effective hardware project, the Nokia Siemens Networks Flexi BTSs (base transceiver station) was presented to the marketplace [5]. That kind of Base transceiver station is energy effectual also attributes multiple-radio telecommunications within a single hardware part. The benefits of such base stations are: minimized fixing time and stuff prices, compressed size also mass (for 25%), lessened energy usage (75%) because of the use of isolated radio heads besides power amplifiers by way of better-quality effectiveness, willingness for consuming renewable energy sources in addition to lithe position: both inside or outside deprived of the requirement for the air-cooling system.

Ericsson Company presented the Ericsson Tower Tube as an illustration of electricity conserving employing an advanced base station location proposal [6]. This is a cost-effective model real tower having lesser ecological influence than conventional steel also using up to 38% smaller amount of electricity from a lifetime perception. It is because of the reality that such an idea is built on powering the base station through wind energy which is located at the elevation of the tower tube, that assists to decrease feeder cost also removes the necessity for dynamic preservation [6]. The idea assists diverse antennas also radio apparatus, multiple-operative location splitting, and supports a lessening of the space hire out by the operators of telecom. Though, to accomplish substantial electricity savings, a methodology founded on the active controlling of the wireless system means appears to be the best auspicious. These anticipations have directed to earlier researches on power energy effectiveness developments at the stage of comprehensive WLANs (Wireless Local Area Networks) [7].

Diamantoulakis and Karagiannidis note that the primary challenge associated with the use of renewable energy resources for powering BSs is the impossibility to adequately forecast the energy demand concerning the concrete region. These forecasts and estimations are necessary to propose the most efficient energy system model for the remote territories, and such forecasts can serve to reduce energy consumption by more than 20% [8]. These data are important to be presented in the feasibility reports. The researchers state that the discussion of the cost-efficiency and feasibility should also be based on the analysis of the mobile user’s activity in different regions because this criterion also influences the overall energy consumption levels [8]. Many national and international corporations presented key research done for similar projects. A detailed feasibility report presented by Victron energy shows capital costs and operational costs for powering a BTS in a rural area states that it would cost over $16000/year, as shown in Table I:

Costs for Powering a BTS.
​Table I. Costs for Powering a BTS.

Another study published by the international telecommunication union (ITU) states that if renewable power generation is to be used to power 118000 new and existing BTSs that is operated by diesel generators it would save about 2.5 billion liters of diesel per year and cut down the greenhouse-gas emissions by up to 6.8 million tonnes. Therefore, help sustain a healthy environment. Furthermore, according to the table below (Table II) using renewable energy to power BTSs might save up to $4.4 billion [9]:

Renewable Energy Costs.
​Table II. Renewable Energy Costs.

GSMA (Group Special Mobile Association) published a chart (Fig. 2) to indicate the growth of BTS in developing areas and a chart (Fig. 3) that shows the viability of using renewable energy source [9]:

Growth of BTS in Developing Areas.
​Figure 2. Growth of BTS in Developing Areas [9].
Viability of Using Renewable Energy Source.
​Figure 3. Viability of Using Renewable Energy Source [9], [10].

When looking closely at both graphs it is clear that if renewable energy sources were used instead of fossil fuels it would reduce operational costs and reduce greenhouse gas emissions [11]. A hybrid energy system may be illustrated as a power generation system wherein the power supply comprises of an amalgamation of two or more kinds of power production sources for example solar PV-panels, wind turbine generators, pico-hydro plants, and diesel generators. The elements used in the hybrid energy system take into account in this project are solar photovoltaic panels, wind turbine generators, batteries, and a conventional diesel generator.

The diesel generator could deliver power at any time, while electricity from solar photo-voltaic panels and wind turbine generator significantly relies on the accessibility of solar heat and wind [5]. It creates the system more consistent, also could be utilized for action when the photovoltaic and wind be unsuccessful to fulfill the load demand as well as at what time the battery storing is washed-out. A hybrid energy system utilizes innovative system controller sense also recognized as a dispatch strategy to manage when electricity must be produced by renewable energy sources also when it must be produced by means like conventional diesel generators. The actual advancement of hybrid energy production is considerate which price investments do not originate from utilizing many influential solar panels or else the utmost effective diesel generator. The hybrid energy system, which is improved in this project, is PV, wind, batteries, and diesel.

Kusakana and Vermaak conducted the simulation to analyze the possibility of utilizing the hybrid system based on Photovoltaic and Wind energy for powering BSs in the Democratic Republic of Congo [12]. The researchers found that in those territories where the wind resources are highly available, BSs working based on hybrid systems are most efficient to address the energy needs of stations. The researchers analyzed the results of the energy production for the Photovoltaic energy system and Wind energy system alone (Fig. 4), and then, the researchers conducted the simulation for the hybrid system. It was found that the capacity shortages were not observed, as a result, it was possible to use the hybrid system to address the complete demands of BSs. The contribution of the Photovoltaic energy system and Wind energy system to energy production was significant, and the use of the hybrid system could improve these results. It was found that with the initial cost of the system in more than $119,000, the cost of the produced energy decreased, and it was 0.37 $/kWh [12].

Average Electric Production for PV and Wind Systems.
​Figure 4. Average Electric Production for PV and Wind Systems [12].

Paudel focused on studying the use of renewable energy resources for powering BSs in the regions of Nepal. The researcher concentrated on analyzing the benefits of using the hybrid solar and wind energy system. It was found that the hybrid systems working according to the direct and indirect mode could produce more energy when the principle of the direct mode is applied because the energy consumption decreases and the non-used energy can be stored [13]. Figure 5 demonstrates that the use of the hybrid system including the photovoltaic modules, wind turbine, and the battery provides the most appropriate amount of energy to support the work of BSs. The focus is on the possibilities of the hybrid model to address the telecommunication load demands in the concrete region. The use of the battery in the hybrid system allowed a decrease in the system’s costs by more than 25% [13]. It was found that the implemented technology is rather promising because of providing an efficient amount of energy necessary to power the BSs in the region.

Optimization Results.
​Figure 5. Optimization Results [13].

The use of such software as HOMER (Hybrid Optimizing Model for Electric Renewables) is discussed by researchers as appropriate to understand and measure how the hybrid energy system used for BSs can produce positive results and address the energy demands in the region [3], [5]. The researchers used the HOMER model to assess the feasibility of the energy system with the focus on such criteria as changes in the load probability and changes in the annual costs [3], [5]. Diamantoulakis and Karagiannidis used a similar model to discuss the efficiency of the system that was presented as the hybrid of the photo-voltaic system, wind energy system, batteries, and diesel generator. It was found that the implementation of such a hybrid system was the most appropriate solution for the Greek territories. The reason is that more than 90% of the produced energy was saved and used to meet the energy demand of the BSs [8].

From this point, the current researches in the field demonstrate that the use of renewable energy sources and the implementation of the hybrid system to power BSs are appropriate approaches to address the problem of energy lack. Moreover, the previous researches indicate that the hybrid systems are not only cost-efficient but also environmentally friendly and based on the widely available resources. Effective energy algorithms and systems can save more than 85% of the energy monthly [3], [5], [8]. The use of energy-efficient techniques for powering BTSs is the priority for telecommunication and mobile companies serving the public in remote areas.

Problem Statement

This project is a design based project and is made to provide a clear understanding of the operation of BTSs and find an appropriate solution to power such devices without having to connect them to a network grid saving Time, money and sustaining the environment. This project proposes a design of an optimized photovoltaic-Solar and wind energy hybrid system to provide power supply to BTS (Base Transceiver Station) instead of using a diesel generator for remote areas. For the proposed hybrid system, we will take the barometric data of stellar insolation as well as wind speed per hour, for remote areas and with the information of design of load usage of base transceiver station and we will design a model using homer software and Matlab for optimization of the hybrid energy system. The hybrid energy system is a combination of wind, photovoltaic-solar, conventional diesel generators, and batteries. Homer software for the optimization of a Hybrid energy system will be used for the examination of sizing and reactivity, will perform to obtain the best achievable formation of a renewable hybrid energy system.

This project aims to hybridize the current energy diesel generator source system with renewable energy sources PV panels and wind turbine generator with design plus optimization. This research also explores the consequence of hybridized diesel generator on:

  • The budget for producing electricity (NPC (Total net present cost)).
  • The working of diesel generator per hour.
  • The lessening in GHG (Greenhouse gases release cost).

The objective is to find the appropriateness of hybrid PV, wind, and diesel generator with battery in the telecom industry, from the perception of practical and financial examination.

Methodology

In association with constructing such a project, brief research was done to provide a clear understanding of the concept. Furthermore, a certain approach must be taken to make a successful project and give the best outcome possible. First, it is essential to find an appropriate BTS load profile associated with each area hence, constructing a sufficient power plan for the relevant load profile. Then, it is necessary to build a simulated design for the power system that would provide maximum supply with minimum costs. Furthermore, a suitable comparison between the project outcomes and others who may have built a similar project and then analyze both project’s data.

This project is related to the population density and therefore it is important to study the population structure in each area as the demand for using BTS service may increase respectively. Finally, as there is a variation in using telecommunication services it is possible to have excess energy from time to time therefore, an energy storage solution must be found. The sizing of a hybrid energy system will be done in a hybrid optimization prototype with the help of HOMER energy software and Matlab Software also system Implementation will do by using this software. The planned hybrid energy system consists of main renewable energy sources wind/PV that will be sited with a backup subordinate non-renewable energy sources diesel generator/batteries, plus converter will comprise in the system to attach betwixt alternating current and direct current links. The HOMER software will be used to find the finest optimum sizing of the system. Reactivity examination is expected to be considered at the time of designing the system. Solar Photovoltaic units would be linked in a combination of series-parallel. At what time the sun rays hit the solar photovoltaic panels, it generates power. It is expected to install a 2-kilowatt solar energy system and additional charges are predicted that are nearly about 6000 dollars and 4000 dollars, in that order. The lifespan of a photovoltaic panel is considered to be 18 years (Fig. 6, fig. 7).

Load Profile for BTS for One day in 1 Hour Intervals.
Figure 6. Load Profile for BTS for One day in 1 Hour Intervals [14].
Global horizontal Radiation.
Figure 7. Global horizontal Radiation.

There are two wind turbines from Bergey Wind Power having the model BWC-Excel-R would be utilized in this hybrid energy system. Each turbine has a rated capacity of 10.5kilo watt also gives direct current. The price of per unit would also be, the major cost is predicted as 17000 dollars, standby cost is predicted as 15000 dollars, plus yearly process and repairs price is predicted as 17 dollars. The simulation program finds an optimum solution, the lifetime of a turbine is taken to be 15 years. The power curve has shown in Fig. 8 and the wind source has shown in Fig. 9.

Power Curve.
Figure 8. Power Curve.
Wind Resource.
Figure 9. Wind Resource.

The annual usage of oil is nearly about 1300 ltr for 2-kilo watt conventional diesel generators. The 1.00-kilowatt diesel generator investment cost, standby cost, regulation cost are 300$, 250 $, 0.100$. The lifespan of a conventional diesel generator functioning time is 16000 hours. The battery type that will be used in this project is Hop-picked. Minimal space 3V, 1800 AH, 4Kilo watt-hour. Such batteries are replaced every 10 years. The one battery initial capital cost, substitution cost, and regulation cost and working cost of $800, $600, and $8 correspondingly. A converter will be incorporated to regulate the flow of electricity betwixt the Alternating current and the Direct current bus. The predictable load is a kind of direct current, however, produced electricity from conventional diesel generator is a kind of alternating current. The size of the converter that will be utilized in the proposed system is 4kilo watt. The early installation cost and substitution cost and function-regulation cost are $3000, $1600, and 30 correspondingly.

A Brief Block Diagram to Describe the Methodologies

A Brief Block Diagram to Describe the Methodologies

​Model Development With Cases

  • Simulation of the System (yet to be completed)
  • Feasibility Report (yet to be completed)

Results and Data Analysis

Development of load profile (development of load profile was done according to data obtained from other similar load profiles)

load data (kW) time
0.8 0:00
0.85 1:00
1 2:00
1.3 3:00
1.3 4:00
1.5 5:00
1.6 6:00
1.5 7:00
1.4 8:00
1.3 9:00
1.4 10:00
1.2 11:00
1.1 12:00
1.2 13:00
1.4 14:00
1.3 15:00
1.6 16:00
1.6 17:00
1.5 18:00
1.4 19:00
1.3 20:00
1.3 21:00
1 22:00
0.9 23:00

Load vs time

Selection of locations and weather data

Georgetown

A small town in Queensland that has a population of 254 people (2006 census) and is connecting Cairns and Normanton. The reason to select such a place is its importance as the main road that connects east and west of Queensland.

Georgetown

georgetown

Falls creek aws

Is a ski resort that is located 30 km from mount beauty in victoria. The reason to choose such a place is its tourism significance as a ski resort in the Victorian Alps and it’s important as a safety precaution to have a sufficient telephone signal in case of a ski accident.

Falls creek aws

falls creek aws

Victoria River Downs

Is a cattle station and is important for the cattle industry in Australia. Due to its large area and remote location, it’s suitable to use a renewable energy source to connect its BTSs.

Victoria River Downs

Victoria River Downs

Moomba

Is a small town but it’s known for its significance in gas exploration and processing therefore, a sustainable mobile signal is important since the town is in a remote location.

Moomba

Moomba A

Yulara aws

It is located near Uluru and it is important as a tourism and recreation place.

Yulara aws

Yulara aws

Laverton aero

Laverton is a small gold mining town and is a proposed highway through western Australia also Laverton has a small airport which makes it important to have adequate mobile signal around the area.

Laverton aero

Laverton aero

Oodnadatta

A small town of 277 people(2006 census) that is mainly a cattle station.

Oodnadatta

Oodnadatta A

Giles met station

Is a weather station and is located in Western Australia. It is important as it is on the great central road and a mobile signal is important to support weather research in this area. Furthermore, tourists are interested in this area as the relies upon weather balloon is attractive sightseeing.

Giles met station.

Giles met

Timeline

It is estimated that the project may require to need two to three months to be accomplished. Such as the project wants the availability of computer labs to use simulation software Matlab and Homer. Additionally, few library resources would be required to organize a thorough in depth study of the project. Below is a bar chart that would outline tasks and the approximate time required to fulfill them.

Timeline

​Conclusion

This projects a proposed hybrid energy system for inaccessible communication areas in Australia. To give well network facilities mobile phone worker will install new mobile phone BTS. Electricity is a core concern for inaccessible or remote regions base station, for the reason that network extension lead is not practicable. This location suggested renewable base hybrid energy system is the best feasible way out. Such way outs of electricity supply to the telecommunication BTS (base transceiver station) are very effectual in terms of cost as well as accessible during the whole year. The condition of respected locations is studied to select the practicable amalgamation of alternate power resources. Alternative energy means are not normally used in tower communication system nowadays however are keenly valued for inaccessible and remote regions across the world. With the assistance of beyond pre-achievability study, the wind and solar hybrid system are the best practical energy solution for cell phone base transceiver stations in Australian spots above diesel generator. While the total estimated rate is high on the other hand the driving and repairs rates are low in comparison with the electricity produced through a diesel generator.

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