There is no uniform definition of a smart grid. According to the European Technology Platform, a smart grid is an electricity network that can intelligently integrate the actions of all users connected to it in order to efficiently deliver sustainable, economic, and secure electricity supplies.

According to the United States Department of Energy, a smart grid is self-healing; enables active participation of consumers; accommodates all generation and storage options; enables introduction of new products, services and markets; optimizes asset utilization; operates efficiently; and provide reliable power quality for the digital economy.

According to the Australian Government (DEWHA), a smart grid combines advanced telecommunications and information technology applications with “smart” appliances to enhance energy efficiency on the electricity power grid, in homes and businesses.

A smart grid includes adding two-way digital communication technology to all devices associated with the grid. A key feature of the smart grid is automation technology that lets the utility adjust and control millions of devices from a central location.

The concept of a smart grid has been around for many years. What's important for us is to understand what a smart grid really means and how it can contribute to national energy policy. The question is, what do we want a smart grid to do cost effectively? One of the key but challenging features of the smart grid concept is customer involvement (customer engagement) in the process of current network structure. The other aspect of a smart grid that is challenging is the use of ICT at all levels.

Fig. 1 shows a conventional (traditional) power system while Fig. 2 shows a future power system.

The traditional power networks can be described as:

• • Centralized power generation.
• • Controllable generation, uncontrollable loads.
• • Generation follows the load.
• • Power flows in only one direction.
• • Power system operation is mainly based on historical data and experience.
• • Overloads in the system are detected by the operators.
• • Rerouting of power flow in the case of overload is performed by the operators.
• • Utilities do not have sufficient information about grid conditions.
• • High power loss.
• • Likely events of costly power blackout.

2.2 Innovations in the power industry to make grids smarter

A major transformation in the electric power industry and energy services is underway. This transformation is driven largely by technological innovation, national regulatory rules, the environment, and economics to make electricity cleaner, more affordable, safer, and reliable. The power industry is moving away from high-carbon technologies toward low-carbon technologies in a very short time, adding significant amounts of solar energy, wind power, and other renewable energy as well as increasing energy efficiency. So, in the future we will see a cleaner energy mix while more new and renewable energy technologies will have low carbon emissions. We also will observe that the electricity networks integrate a mix of central power stations and distributed low-voltage generators. By adding more state-of-the-art digital sensors at every corner of the grid, the power industry can better control its interconnected networks. The first digitization move began with smart meters.

Power companies will be able to provide distributed generators, both on the supply side and the demand side. The power industry will also be able to provide a range of customized services to meet a customer's needs and his or her growing expectations (e.g., some commercial customers want 100% renewable energy to meet the company's sustainability goals).

Shifting from high carbon generation technologies to low carbon generation technologies has resulted in lower prices and greater availability. Now, renewable energy is an important part of the world energy mix.

If power companies can deliver electricity more efficiently and teach customers to use it wisely, then power companies can do more to use energy's potential to grow the economy.

With the rollout of the Internet of Things (IoT) at homes and businesses, customers will have more control over all their electrical devices. The IoT will provide the opportunity for customers to control temperature, lighting, home security, choice of energy, etc. The IoT will also provide the opportunity for effective integration of EVs to the grid. Distributed EVs will help stabilize the electric power network.

The evolution of the smart grid means that power industries around the world are in transition to a new environment defined by advanced information and control technologies. This smart grid will provide an opportunity for customer engagement, converting passive customers to active customers while enabling customers to better control their electricity consumption in an efficient and cost effective way. Digital, distributed, modern, and smart power grids will make cities smarter by making the electricity that power companies supply to their customers more secure, reliable, affordable, and clean.

The new generation of power grids will provide an opportunity to customers for the integration of renewable and low-carbon energy sources such as solar and energy storage, hence reducing gas emissions in the electricity generation sector.

Smart grids also deploy new automated technology that improves the resiliency and flexibility of the grid, providing real-time visibility for power system operators in the case of multidirectional power flow. Using intelligent sensors and switches will help systems self-heal by automatically detecting and isolating faults and redirecting the power flow.

2.3 Electricity networks worldwide face a number of challenges

They have aging infrastructure, continuous growth in demand, shifting load patterns, and supply more power using intermittent sources.

Power utilities are facing many challenges, including increasing grid resilience, improving customer engagement, managing the operation of advanced metering infrastructure (AMI), preventing meter malfunctions, optimizing the maintenance of network assets, etc.

Power utilities will be able to solve these challenges by applying big data, cloud computing, and machine learning.

In the near future, we will see that every electrical device, both domestic and commercial, that is connected to the electricity network will have an Internet address. Examples include air conditioning, toasters, the inverter of rooftop solar PV systems, street lighting, EV battery chargers, etc. This will be the so-called IoT, leading an evolution of the grid and all devices connected to the grid to be more digital.

2.4 Some customers demand individualized services

In addition to having reliable, safe, and affordable electricity, some customers demand very high levels of service quality such as stable frequency and voltage, very high reliability, or an especially low carbon energy source. Some customers even want a high degree of engagement with their energy use.

2.5 What factors make an electricity grid smart?

There are a number of factors that make the grid smart:

• • Know exactly where a power failure happens and quickly fix it.
• • Extend life of aging equipment.
• • Detect and minimize outages by sensing potential equipment failures.
• • Reduce power loss by using real-time data to match generation and demand.
• • Smooth power demand to take advantage of off-peak supply.
• • Maintain a sufficient, cost-effective power supply while managing a GHG target.
• • Make it easier for consumers to use renewable energy sources.
• • Use meters that show consumers their energy use in real time.
• • Use variable pricing that allows consumers to choose off-peak energy.
• • Help customers to establish a “smart home” that turns appliances on and off.

A smart grid is beneficial for both customers and power utilities.

2.6 Customer side

Because of a lack of visibility, consumers can’t be expected to manage what they can’t measure or see. The smart grid overcomes this “lack of energy visibility,” making real-time usage and pricing data available through:

• • In-home displays. This will help consumers to identify energy-intensive appliances that they have and use.
• • Online portals.
• • Smart phones.

Making customers aware of demand management methods. This will help consumers:

• • Reduce energy use during peak times.
• • Slow the need for investments in costly generation, transmission. and distribution infrastructure.
• • Improve reliability and reduce the overall cost of supply, etc.

2.7 Utility side

The smart grid has benefits for utilities. These include:

• • Better managing the grid.
• • Offering customers choices.
• • Understanding energy usage.
• • Reducing cost of electricity.
• • Communication with customers.
• • Communication with customers’ appliances.
• • Using more renewable sources of energy.
• • Integration of EVs.

One of the important features of a smart grid is so-called self-healing. A self-healing smart grid can provide a number of benefits that lend themselves to a more stable and efficient system. Three of its primary functions include:

• • Real-time monitoring and reaction, which allows the system to constantly tune itself to an optimal state.
• • Anticipation, which enables the system to automatically look for problems that could trigger larger disturbances.
• • Rapid isolation, which allows the system to isolate parts of the network that experience failure from the rest of the system to avoid the spread of disruption, enabling a more rapid restoration.

As a result of these functions, a self-healing smart grid system is able to reduce power outages and minimize their length when they do occur. The smart grid is able to detect abnormal signals, make adaptive reconfigurations, and isolate disturbances, eliminating or minimizing electrical disturbances during storms or other catastrophes.

An EV is any vehicle that uses electricity for propulsion rather than liquid fuels. Fig. 1 shows the major operational differences between an EV and an ICE vehicle.

The idea of a vehicle propelled by electricity was first conceptualized in the 19th century, and EVs had been manufactured and used in the same century, shortly after the invention of rechargeable lead-acid batteries and electric motors. However, with the development of ICEs, EVs were quickly considered to be an unviable transportation option due to their limited range, power, and durability as well as the large availability of gasoline for ICEs.

Nowadays, with growing concerns for CO₂ emissions and the growing scarcity of fossil fuels, EVs are quickly becoming a viable alternative to the ICE. Because of the environmental benefits associated with EVs, prevalent advancements have been made in the EV industry to influence the uptake of these economically and environmentally beneficial vehicles. These advancements have been seen in battery technologies as well as the integration of energy conservation options, such as regenerative braking.

A major issue that has sparked consumer interest in the ICE over the EV is the difference in range capabilities. Range anxiety is a term commonly associated with the limited range capabilities of EVs compared to ICEs, which has greatly influenced the unpopularity of EVs in the past. To overcome the range issues, advancements in battery technologies, improvements in vehicle efficiency, or the widespread rollout of charging infrastructure are required.

3.2 EV historic timeline

• • 1859: Invention of Lead Acid Battery by Gaston Plante.
• • 1879: Thomas Edison installs Electric Lights in New York City, popularizing Electricity.
• • 1891: First Electric Vehicle is built in the United States.
• • 1897: First Commercial US Electric Vehicles. Electrobat Taxis hit the roads in New York.
• • 1933–45: German, French, and Dutch automakers sell a small range of EVs, spurred by gas shortages and WWII.
• • 1949–51: In Japan, Tama Electric Motorcars sells an EV during a severe gas shortage.
• • 1960: Automakers experiment with EVs, though none are widely adopted.
• • 1996: General Motors begins leasing the EV1, one of several electric brands rolled out to meet California's Zero Emission rules.
• • 2010: Nissan delivers the Leaf, an EV with a 100 mile range, a lithium ion battery, and regenerative braking.
• • 2011: The Tesla Roadster electric sports car is offered. It has a range of 245 miles.

Fig. 3 shows the differences between an EV and an ICE.

3.3 EV types

EVs come in three types:

• ▪ Battery electric vehicles (BEV)
• ▪ Plug-in hybrid electric vehicles (PHEV)
• ▪ Hybrid electric vehicles (HEV)

The BEV operates on electric power only, and for this reason, it does not directly cause any carbon emissions. The BEV's indirect cause of CO₂ emissions is entirely dependent on what means of generation was used to produce the electricity used to charge the vehicle. The PHEV is a hybrid vehicle which is driven by an electric motor but also has a back-up ICE, which is used to recharge the battery while driving. Both the BEV and the PHEV can be plugged into the electricity network to be recharged. The HEV combines an ICE with an electric motor, where the electric motor is used to supplement the combustion engine to provide better fuel economy. The HEV cannot be connected to the grid, where the electric motor is charged from the ICE [1].

3.4 EVs and the smart grid

EVs are becoming an alternative to the conventional ICE vehicle, and will soon become an integrated part of the electricity network. Without applying any control over the charging behavior of EV owners, peak demand could be significantly increased beyond the delivery capacity of electricity networks. Communication between the electricity company and EV owners is made possible with an advanced electricity meter called a smart meter, which can provide the consumer with useful information.

The smart grid is often thought of as a grid that enables closer integration between electricity supply and demand as well as two-way communication between the electricity company and customers via smart meters by using new modern communication technologies. Smart meters can be used to encourage EV owners to charge their EVs outside times of peak demand. Furthermore, EVs can be charged at times when there is excess solar photovoltaic (PV) generated electricity, thus they can aid in the integration of renewable energies. Also, provided that the EV supply equipment is capable of both delivering and receiving energy to and from the EV's battery, consumers can be further encouraged to provide electricity during times of peak demand through vehicle-to-grid (V2G) or vehicle-to-home (V2H) support. An in-vehicle device proposed in this paper is to maximize the consumer's understanding of how they can optimally manage their EV, which would result in a smoother rollout of EVs on a large scale. Providing an in-vehicle display will encourage the EV owners to adopt smart charging strategies by informing them of the benefits that may be gained from the adoption of such strategies. Furthermore, the scope of smart charging can be extended to ensure that users charge when the electricity mix on the network has a large renewable density, meaning that the indirect cause of CO₂ emissions from EV operation is far lower than if the electricity was predominantly generated by, for example, a coal-fired power station.

3.5 EV integration within the smart grid and its impact on electricity networks

The impact that EVs have on electricity networks, given that the appropriate preparation is made, could be positive rather than negative. As stated in Ref. [2], the integration of EVs could present a great opportunity for improving both the efficiency and reliability of networks on a large scale. This is because, if operated properly, EVs can be used to provide support to the network during times of peak demand. This can be achieved by discharging the energy stored in the vehicle's battery to the grid to alleviate much of the stress that the network might be experiencing (a process called vehicle-to-grid (V2G) support).

Furthermore, if the EVs are then charged during times of low demand, such as in the early hours of the morning, much flatter load profiles for the electricity network will be seen, which in turn will dramatically improve the network's efficiency. Because this would result in a decentralized form of generation, improved reliability would also be seen, although this factor would depend on the prevalence of EV deployment. Another benefit associated with EV integration is the improved integration of decentralized renewable energy sources.

3.6 Feature requirements for in-vehicle display unit

The fundamental issues associated with the EV industry include the indirect cause of GHG emissions, integration costs and impacts, potential support to integrating renewable energy sources, and potential support to stabilizing the electricity network. The purpose of the device proposed in this paper is to maximize the consumer's understanding of how they can optimally manage their EV, when driving, charging, or discharging, which will subsequently lead to a smoother rollout of EVs on a large scale. For this reason some of the features that need to be included in the proposed device are discussed here.

• • Battery characteristics: The key parameters that describe the battery's current condition include the state of charge (SOC), state of health (SOH) (in terms of cycle count), and the calendar life (based on the average number of cycles used per day). Each of these key parameters must be included as features of the display board.
• • Travel information: An important feature of this device would be a traveling guide. This would include road maps, including charging infrastructure locations. The guide would also require the capability of determining the optimal/shortest route for certain trips, including the shortest additional route required for driving to a charging station part way to the desired destination for that trip. For this reason, the guide would need to predict the energy consumed for the trip, and thus what the SOC would be upon reaching the destination.
• • Electricity network: Important information describing the electricity network and its current and future status would need to be available to ensure that the consumer would be able to optimize their EV management strategy. This includes information regarding electricity prices, system load (i.e., what percentage of the system's maximum capacity is the current load), and future forecasts for these two parameters (provided either by the distributor or via another means).
• • Charging/discharging schedule: The optimal scheduling scenario is one where the distributor organizes the schedule for the various consumers. This is because the distributor can receive information on the travel requirements of its respective consumers, and thus organize a schedule that both satisfies these requirements and ensures the system will not be overloaded.

A considerably lengthy low-demand time frame exists from late at night to the early hours of the morning. This time horizon would be the optimal period for EV charging in most cases. Furthermore, in markets that use time of use (TOU) tariffs rather than a real-time pricing scheme, the price of electricity would generally remain unchanged for this entire period.

On the consumer end, information should be provided on the possible charging timeslots for the EV, based on the expected charge duration. The duration itself will be provided to the consumer as well as a comparison of the expected total cost for each possible timeslot. Once a timeslot is selected, this decision would be sent from the display board to the smart meter, where it could then be transmitted to the distributor to organize the command required to trigger charging at the chosen time.

A similar procedure as mentioned above can be applied when choosing the times for providing ancillary support (i.e., V2G) where optional timeslots will be available to the consumer, who can then choose the timeslot they prefer, and information on the expected duration and revenue received will be provided. The charge/discharge management flow chart is shown in Fig. 4. During the charging schedule, it would be important to monitor the energy management (EM) of the power entering the battery to understand the equivalent amount of CO₂ (g/kWh) indirectly emitted from the energy stored in the battery.

• • Economics: The last and possibly most critical feature of this display board is the information regarding the economics of the EV. The EV economics should describe the overall financial return that consumers can reap from their EV, which effectively classifies the EV and its battery as a means of investment.

The economics should address the following aspects: (i) battery equivalent wear cost; (ii) revenues received and expenses incurred due to charging and discharging; and (iii) other savings or income due to incentives.

The total profit or loss can be measured over the lifetime of the battery, which will take into account each of the key costs mentioned above. Based on the provision of this information, a financial summary can be compiled at the battery replacement date, stating overall how the consumer profited from the demand side management (DSM) practice that was adopted.

The last feature that can be incorporated is advice or recommendations on how costs can be further minimized and revenues maximized based on the consumer's practice of DSM.

3.7 In-vehicle communication board

The development of an in-vehicle communication board involves establishing the various display features that would provide comprehensive information to the owners of the EV about conditions of the electricity grid, the EV and its battery, pricing options, and charging and discharging schedule options. This is necessary information that EV owners need to know before connecting their EV battery to the electricity grid. Electricity costs at the time of EV-grid connection is an important factor. These costs include the purchase price of electricity for charging, the selling price of electricity for discharging, and the equivalent battery wear costs that are based on the limited energy throughput of the EV's battery.

Having considered these factors mentioned above, the optimal smart charging practices could be obtained by determining those that yielded minimal costs. Smart charging practices typically involve charging when the electricity demand is low and discharging when the demand is high. The adoption of these practices would therefore result in the flattening of network load profiles. The adoption of smart charging practices can yield significant benefits to the operator of the EV, which in turn can benefit the electricity distributor by minimizing the effect that the EV will have on the electricity network.

The disadvantages of EVs have been their high cost, low top speed and short range. Hybrid plug-in electric vehicles (HPEVs) using an electric battery in conjunction with a conventional internal combustion engine have been on the market for more than 25 years. Developed in response to escalating fuel costs, they can be run on a charge-depleting mode (using the battery) or a charge-sustaining mode (using the fuel). Developments in battery technology have enabled auto manufacturers to develop pure plug-in electric vehicles (PEVs), of which an increasing number are on the market. EVs are more energy-efficient than conventional vehicles and dramatically cut CO₂ emissions.

From the grid point of view, the EV is considered as an electrical device representing a new demand for electricity during the periods that EVs need to be charged, but they can play the role of storage device that could supply electric power back to the grid.

Through an effective communication with the grid, the EV battery can be used as a storage device that can make the electricity grid more reliable, especially with large proportion of renewable sources such as grid-connected solar and wind.

3.8 Challenges

• • Cost
• • Range limitation
• • Safety and reliability
• • Progress through R&D
• • Driving adoption through education

3.9 Opportunities

• • Government funding for research will be helpful for technology advancement and cost reduction.
• • International R&D cooperation and coordination can help address common areas of need, accelerating technological breakthroughs.
• • Consumer education campaigns and clear fuel economy labeling can help enhance public awareness.
• • Etc.

3.10 Research questions

• • How significant is the impact of charging and discharging of EVs on electricity demand, specifically in regional areas?
• • Is the existing distribution network infrastructure capable of handling the increase in demand associated with widespread EV uptake?
• • What is the best method of charge management to cope with the increase in electricity demand?
• • How will the extended range of new EVs, such as Tesla and the Nissan Leaf, impact customer charging behavior?
• • What costs can be expected for consumers charging EVs on existing distribution networks? And as a consequence, how will the consumer's ability to exploit time of use rates affect electricity demand?
• • What benefits can “smart” technology provide in reducing the impact of EV charging?
• • Understanding vehicle use profiles, EV benefits, and battery life challenges.
• • Integrating renewable resources (solar and wind) with vehicle charging.
• • Developing and testing grid interoperability standards.
• • Exploring grid services technology opportunities.
• • Wireless technologies for communications and control of EV systems.
• • Monitoring and sense-and-control of charging.
• • Software systems for EV energy management.
• • Smart charging infrastructure.
• • EV fleet management technologies and services.
• • V2G and V2H.
• • Smart charging infrastructure and scalability.
• • Environmental issues and benefits.
• • Energy management.
• • Role of renewables in EV integration, especially solar and wind.
• • Power quality, reliability, and stability effects as a result of EVs.
• • Customer adoption, customer behavior and customer response.
• • Pricing models for charging stations, roaming across territories.