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Engineering » Electrical and Electronic Engineering » "Development and Integration of Microgrids", book edited by Wen-Ping Cao and Jin Yang, ISBN 978-953-51-3400-8, Print ISBN 978-953-51-3399-5, Published: August 16, 2017 under CC BY 3.0 license. © The Author(s).

# Future of Microgrids with Distributed Generation and Electric Vehicles

By Syed Abid Ali Shah Bukhari, Wen-Ping Cao, Toufique Ahmed Soomro and Du Guanhao
DOI: 10.5772/intechopen.68819

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## Overview

Figure 1. Projected emissions by country.

Figure 2. Electric cars’ carbon emissions.

Figure 3. World’s energy poverty density.

Figure 4. Africa’s energy poverty density.

Figure 5. Range Rover Evoque electric vehicle.

Figure 6. Jaguar F type.

Figure 7. Growth in electric cars in UK.

Figure 8. Energy density trend for battery.

Figure 9. Cost of electric vehicle battery storage to consumers in two annual energy outlook (AEO).

Figure 10. Microgrid architecture and applications.

Figure 11. Flow control valve, pressure gauges, and process flow lines.

Figure 12. Microgrid with solar array and wind mill.

Figure 13. Microgrid revenue by forecast scenario, world market: 2013–2020 [38].

Figure 14. Domestic electrical vehicle charger.

Figure 15. Building the dedicated WEVC on major express ways.

# Future of Microgrids with Distributed Generation and Electric Vehicles

Syed Abid Ali Shah Bukhari1, Wen-Ping Cao1, Toufique Ahmed Soomro2 and Du Guanhao1
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## Abstract

This chapter examines the current energy scenario for microgrids over the world and discusses the challenges and opportunities due to the increasing penetration of distributed power generation systems and electric vehicles (EVs) into the microgrids. Wind power and solar power can be generated by wind turbines and photovoltaics, respectively, while these are intermittent in nature. EVs and hybrid EVs use a battery energy storage system and charging facilities while the latter also include an Internal Combustion Engine (ICE) to provide an extra energy source. The features of these systems in the context of microgrids are studied in detail, in terms of their components, efficiency, reliability, charging and discharging arrangements, active and reactive power control. The chapter provides a reference to the development of microgrid systems especially for developing countries.

Keywords: Batteries, Carbon Free Generation, Charging and Discharging, CO2 Emissions, Electric Vehicles, Microgrid, Renewable Energy

## 1. Introduction

Currently, air pollution is a serious issue, especially in heavily populated cities, such as London, Paris, Beijing, and Tokyo. Approximately 25% of global CO2 emissions are due to passenger road and air travel, and the transport of goods. In addition to CO2, Sox and Nox are also generated. Although, cars and trucks are responsible for the bulk of these of emissions, about 75% worldwide emissions due to aviation and shipping are growing rapidly too, and the energy used in transport could double by 2050 [1]. The chart of projected overall CO2 emissions by different countries is depicted as shown in Figure 1 [2], and particularly CO2 emissions by electric cars by different countries are shown in Figure 2 [3, 4].

#### Figure 1.

Projected emissions by country.

#### Figure 2.

Electric cars’ carbon emissions.

Therefore, CO2 emissions need to be cut by approximately 50%. Priority should be given first to research technologies and practices that are mostly cost effective. Microgrid and E-propulsion systems have the capability to enable this; thus, bringing about a revolution in low CO2 emission technology [5]. Thus, for the developing zero-emission, electric vehicles have become the key logical and scientific research project in many countries around the world in the twenty-first century [6]. The dynamism and energy saving motor drive technology have developed one of the key points to electrical vehicles commercialization [7].

As EVs are suitable, progressively more essential not only because they decrease noise and greenhouse gases but also they are able to diminish the dependency of carrying oil, as the power is generated from fuels other than oil [8]. Electric vehicles can contribute to decrease carbon emissions. The zero release of CO2 production necessitates that the EV energy should be produced from alternate sources like nonfossil fuel, for example, nuclear and unconventional sources of energy. Actually, the most dangerous situation is that there is merely 40 years of oil supply is left [9, 10] with the rates of current usage. In fact, increasing inadequacy may bring the consequence in the huge amount of rises in price and ultimately the practice of continuous oil usage and extra fossil fuels will never be lavishly practicable, hence sources of oil might be well-maintained, as the procedure of consumption will decline. The production of oil can also be achieved from other fossil fuel sources such as coal [11]. Normally in this way, oil production is deliberated to be round about 10% more costlier.

This chapter provides a brief overview of the recent energy crisis in all over the world and the comparison between an electric vehicle and gasoline vehicle, and the methods by which driving range of electrical vehicle can be enhanced with the help of microgrid. The proposal which actually necessitates the development of microgrid technologies on the basis of different reasons and their implementation with respect to electrical vehicle and issues associated with the energy crisis is also given. The main purpose of this chapter is to lump together plug-in vehicles and electrical vehicles with microgrid.

### 1.1. Electrical energy scenario and background

The most complex and largest machine which has been ever built by the human brain is actually the electric grid. We found electricity 100 years ago. But still very much a dark planet, still a lot of places in the world there have not had an access of electricity in the last 100 years [12]. Even people living in some places do not know what electricity is [13]. So, just like many others, engineers and a group of some technical persons, if we could create an open source movement, an elaboration to build something and to start thinking about how would we electrify placed out there that governments have forgotten about. The first business should be to plan together and to find the ways to build the future. First of all, one block of location or something nearer and something that would benefit from what we are doing. So if we look at the statistics which is shown as below.

### 1.2. Energy poverty statistic

One in five people in this world do not have access to electricity today and it is approximately 1.2 billion people globally. If we start to look in depth that where are these people? Three of five in Africa, primarily in the rural population, have no access to electricity today [14]. If we further look at the statistics, where is the growth going to be? Where are all those new children going to be in the year 2100? The statistic of world’s energy poverty is shown in Figure 3, and the statistic of Africa’s energy poverty is shown in Figure 4 [15].

### Figure 3.

World’s energy poverty density.

### Figure 4.

Africa’s energy poverty density.

It will be approximately 10 billion people in the year 2100 [16] and in Africa, it will be 3/2 billion people. Africa’s land mass is three times bigger than the United States and Africa’s population is 750 million people today and it is 4 times more [15]. The area is full of poverty and full of orphans because of HIV [17]. Now, if we try to figure out how can this community be upgraded? Let's see if we can create an open source collaborative approach to electrify this rural population, and there must be an impact on all of the community. Just for example as the first thing which is needed is an affordable and reachable electrical power, a nice thing in Africa. Everybody has cell phone and people mostly walk 5–10 miles to charge the mobile battery for their cell phone [18], so what if they could do that at home with the help of microgrid and in this way, business of microgrid will be growing. The second point is we have to be sustainable and have to keep the environment green. No greenhouse gases, no nitrous, no methane, and no carbon dioxide. So what do we have to do for alternative sources? We have lot of wind as well as lot of sunshine for photovoltaic (PV). Finally to reduce usage kerosene in homes. As kerosene is the primary source of cooking and lighting in the developing world. It is very dangerous and very polluting.

### 1.3. Electric vehicles

A vehicle that uses one or more electric motors or traction motors for propulsion.

As the worldwide economy originates to strain under the burden of increasing petroleum costs and environmental distresses, studies have encouraged the growth of numerous categories of clean energy transportation systems, for example, hybrid electric vehicles (HEVs), battery electric vehicles (BEVs), and plug-in hybrid electric vehicles (PHEVs).

Plug-in hybrid electric vehicles are already playing an important role in minimizing greenhouse gas emissions, as these emissions are very hazardous and are the main cause of global warming [19]. Therefore, electrical vehicle technology, electric vehicles (EV) and plug-in hybrid electrical vehicles (PHEVs), have gained the momentum in recent years and have become the focal point of research and development in finding suitable replacements for the internal combustion engine [8]. As internal combustion engine vehicles are being converted into EV, increasing amounts of oil will be saved. However, the energy for the innovative EVs will have to be generated in addition to the electricity used for surviving purposes [20]. Furthermore, there is also a need to upgrade the existing power grid if large number of EVs/HEVs are connected to it. To tackle this problem, a current trend is to develop microgrid [21]. This will not only necessitate a considerable enhancement in electricity generation, but also the microgrid distribution will have to be planned for [22]. The electric vehicles by Range Rover Evoque and Jaguar F type are shown in Figures 5 and 6 [2325].

### Figure 5.

Range Rover Evoque electric vehicle.

### Figure 6.

Jaguar F type.

Particularly, PHEVs obtain the most consideration because of combining electrical source and conventional engine. This kind of vehicle makes available the buyer a significant pure electrical choice and also an extended range, which is able to perform by means of a conventional internal combustion engine (ICE). The literature reveals that sales in electric cars have been tremendously increased in recent years. The UK growth in electric cars data taken by SMMT from 2011 to 2016 is shown in Figure 7 [26], and the overall sales in electric cars are shown in Table 1 [27].

### Figure 7.

Growth in electric cars in UK.

YearNumber of electric cars on the road
201025,000
201180,000
2012200,000
2013405,000

### Table 1.

Electric car sale accelerates.

Due to above-rising trend in sales scenario of the electrical vehicle on the road, the demand of power is growing at an approximate rate of 100% per annum for the last 4–5 years and it is obviously anticipated that the growth in average demand over the upcoming decades will be bigger. This is an indication of load demand anxiety and stress on the distribution grid station in the years ahead, and much would be expected from electricity service provider so as to operate in such a way that it can satisfy customer needs and also enable it to stay in effective business.

The establishment of a rechargeable energy storage system (RESS) that has a provision of the output power during acceleration, proficiently use the regenerative energy to achieve a considerable cycle life is the serious aspect to be met by battery technologies.

### 1.4. Gasoline vs electric vehicles

The comparison between electric and gasoline vehicle is shown in Table 2 [28].

Electric vehicleGasoline vehicle
Requires utility company for chargingOrganization of petroleum exporting countries (OPEC)
200+/− mile range300+ mile range
Zero emissionHuge greenhouse gases/pollution
Hours to chargeMinutes to refuel
2 cents per mile12 cents + per mile

### Table 2.

Comparison between electric vs gasoline.

By considering Table 2, in contrast to gasoline/patrol vehicle, the electric vehicle has 6× lower cost for a 1-mile drive. However, its driving range is only 1/3 of gasoline vehicle per full charge. And this is the main drawback [29].

### 1.5. Improvement in driving range

The storage of electricity and resultant mass is shown in Table 3. We can enhance the range of driving by the accumulative capacity of the battery. But then, again at what expense? In order to have heavier and bigger battery, there is a need that it must have the greater energy density to be higher, so more costly battery/car hence lesser price charge of a storage battery is required. The trend of battery energy density is shown in Figure 8 and the cost of electric vehicle battery storage to consumers is shown in Figure 9 [30].

Battery technologyEnergy/WeightEnergy/VolumePower/WeightRelativeSelf-dischargeRecharge time
Watt h/KGWatt h/LWatt/kgCostRatesHours
Lithium/Ion1602701800410%2–4
Li-Ion Polymer130–2003002800410%2–4

### Table 3.

Storage of electricity and resultant mass.

### Figure 8.

Energy density trend for battery.

### Figure 9.

Cost of electric vehicle battery storage to consumers in two annual energy outlook (AEO).

### Figure 13.

Microgrid revenue by forecast scenario, world market: 2013–2020 [38].

Charging levelPower supplyCharging powerMiles of range for 1 h of chargeCharging times
BEV
Charging times
PHEV
Level 1120 VAC Single phase1.4 kW @ 12 amp (on-board charger)̴3–4 miles̴ 17 h̴7 h
Level 2240 VAC Single Phase up to 19.2 kW (upto 80 amp)3.3 kW (on-board)̴8–10 miles̴7 h3 h
6.6+ kW (on-board)̴17–20 miles̴3.5 h̴1.4 h
DC fast charger level 2200–450 VDC upto 90 kW (approx.: 200 amp)45 kW (off-board)̴ 50–60 miles (80% per 0.5 h charge)̴ 30–45 min (to ̴80%)̴ 10 min (to ̴80%)

### Table 4.

Charging standards and costs.

Table 4 shows the types of chargers according to different levels; however, the rate of one direct current fast-charge (level 2) is the identical as the cost of one 24 kWh battery, which is used by Nissan LEAF; therefore, constructing additional charging stations will accelerate occasion of opportunities to install lesser capacity of battery, consequently proposing an inexpensive electric vehicle. The domestic electrical vehicle charger is shown (Figure 14) [48].

### Figure 14.

Domestic electrical vehicle charger.

### 2.5. Suggestions for further improvement in microgrid

• Building the future for EVs

• Licensing of third party activities

• Microgrids for local power generation–peak shaving and commercial prospects for trade of surplus energy back into grid

• EV battery charging, rental, replacement services

• Software and mobile applications to find the nearest charging station

### 2.6. Future of charging stations

For the future of charging stations, the private companies are already developing their electric vehicles charging solutions [49]. However, building a strong infrastructure for EV charging can overcome the problem of low mile range. Still, there are many efforts and initiatives, which need to be taken for building the case for wireless electrical vehicle charging (WEVC) up to mainstream. The government should distribute its available resources in the favor of research in electrical vehicle demands. Like: (1) low price and availability of power supply to drive electrical vehicle demand, or vice versa. (2) The wireless charging lines on major expressways which are shown below in Figure 15, and building the smart metering system with the secure payment for the wired and wireless electrical vehicle charging. Beyond the EV-Extension of Wireless Transmission Applications. Infrastructure availability for EV charging (lowering power supply costs). Directly lowering EV costs (increasing EV demand). With EVs capable to simply and easily locate charging facilities/achieve and get charging on the move when required. Have need of complementary enhancements in smart powering and metering systems for calculation and payment of charging fee.

### Figure 15.

Building the dedicated WEVC on major express ways.

### 2.7. Room for Improvements

Rates of enhancements enabling development in use of microgrid, electric vehicle, and expertise in transfer of power without wire: such as

• ICs

• MOSFETs

• Roll printing for thin film substrates

The improvement rates in the above skills exceed the rate of extension in (car) battery skills. Consequently, the task in short mile range of electric vehicle will be overcome more rapidly while smoothing the advance of economical wireless facilities for charging, through powered microgrid. The implementation of the above-mentioned suggestions will lead to a healthier and sustainable life, which is depicted in building the dedicated WEVC on major expressways as shown in Figure 15 [50].

## 3. Conclusion

This chapter has presented the development of microgrids incorporating renewable energy and electric vehicles while the associated energy crisis and their challenges have been extensively discussed. Addressing these challenges would contribute to simplifying the execution of novel renewable technologies in a microgrid. As the microgrid research involves many areas of power systems by considering the latest trend, charging infrastructure can be developed to better cater for EVs in the future. Also, the worldwide anxieties about diminishing fossil energy assets and ever-increasing pollution have augmented significantly in recent years. Distributed generation and EVs have acknowledged enormous consideration because of their environmentally friendly nature as a power source.

The impact on the grid can be reasonably eased by means of developing smart onboard or offboard charging facilities in residential or office areas. These approaches permit a high quantity of EVs to be fast charged with a minor impact on the main grid and an increased DER self-consumption. With the help of microgrids, EVs can reduce the reliance on crude oil fossil fuel energy so as to reduce CO2 emissions. The record numbers of EV chargers based on microgrids and charging infrastructures are anticipated to rapidly increase surrounded by domestic areas in the near future.

The future microgrids will have a huge quantity of distributed generation systems and adaptable power generation from renewable energy resources. As microgrid systems can provide much promise for integrating large numbers of distributed energy resource systems and minimise the impact on the main grids, their future are bright. In addition to the electric vehicle application, microgrid technologies can also be applied to aircraft, rails, ships, submarines or other forms of electrified transportation.

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