With the developing worldwide patterns in the area of Smart Cities and Smart Energy, the requirement for maintainable ways to deal with sufficiently deal with the flexibly and transformation innovations with applied interest for the present and future has been recognized in the standard. Quick development in the areas of Information and figuring advancements features the capability of including the ideas of Artificial Intelligence and Internet of Things to itself to the additional expansion of the quality and ways of life with included advantages to the administration different levels (Reyter et.al, 2009). This fundamentally includes the exploration systems concerning most appropriate operational methodologies, computerization, and perception. The accessibility of information with surrounding insight procedures can prompt more precise figures of future requests to encourage the extent of cutting edge energy frameworks.
Fluffy rationale regulators (FLCs) are based basically to expand the human actuated conduct for improved execution and computerized plan system when contrasted with MPC (Eynard, 2010). Worldwide business sectors are set to address Energy proficiency as far as low carbon discharges and develop into the fragment of E-Mobility. To encourage further decarbonisation of the previous power lattice, it is imperative to move towards power-based warmth sources (Werner et. al, 2014). The headway in the observing and symptomatic strategies is seen through the fuses of Artificial Neural Network (ANN) calculations (Mavromatidis et. al, 2013). Moreover, the incorporated energy approaches and more productive information taking care of procedures through reasonable Building Information Modelling (BIM) strategies present the open door for intercessions and adjustments (Zhang et. al, 2018). Significant commitments to Intelligent Energy Systems include satisfactory use of accessible information to create sound and exact models which further upgrade the warm and electrical conductivity of the structures. An ANN-based methodology is discovered to be viable for power utilization determining.
Decarbonisation of intensity frameworks with fast headways in the electric-vehicle (EV) area has prompted EVs to turn into an altogether alluring lower carbon choice (Hayes et. al, 2017). Various driven tasks zeroing in on the advancement of adaptable Smart Energy intercessions are right now in progress, as a component of the EU H2020 call for Smart Cities and Communities. Their thought process is to accomplish coordinated business scale arrangements with a philosophy of a possibly high market driven element where energy, transport and Information, and correspondence innovation assume a significant job.
Key words: Intelligent Energy Systems, Sustainability, Smart City, Energy Management,
Surrounding Intelligence alludes to electronic frameworks that are delicate and receptive to the presence of individuals. The establishment of savvy energy frameworks is laid upon by the model of present-day mechanical subordinates which coordinate hardware into the constructed climate, bringing about pervasive figuring among individuals and articles or gadgets that are at last consistent, bother free, and secure. Data and correspondence advances (ICT) are considered as one of the segments of practical energy frameworks which are around the world perceived for observing and overseeing frameworks in this way prompting counteraction or decrease of regular and human instigated calamities through early expectation or cautioning by the arrangement or possibly solid choices to oblige the situational perspectives. Breaking down the advancement towards manageability has certain methodological restrictions with differential ideas of study which has presented challenges in the supreme estimation of qualities or choosing the satisfactory arrangement of utilization. The Energy-based approaches manage the general decrease of petroleum product use by focusing on energy effectiveness through the conceivable joining of sustainable sources. This when combined with the Ambient Intelligence or shrewd innovation, prompts the conceptualization of building climate coordinated in the Internet of Things (IoT) to accomplish more astute and solid frameworks. The European Commission has set the Renewable Energy Directive, which has set feasible focuses for the nations in the European Union (EU) for the advancement of Renewable Energy sources. The principal objectives are a 20% decrease in ozone-depleting substance outflows, 20% environmentally friendly power utilization, and a 20% decrease in energy utilization constantly 2020 when contrasted with the most recent decade by consideration of practical frameworks in the areas of power, warming, and cooling, and transport.
An investigation by the United Nations features that urban communities involve fewer than 4% of the world's property territory, however burn-through over 75% of normally accessible assets delivering around 65–80% of ozone harming substance discharges at a globalized level. The emanations are anticipated to increment with the worldwide guidelines of urbanization attributable to 54% of the total populace today, which is anticipated to additional expansion to 66% continuously 2050. Expanding asset effectiveness at the city scale would empower all the more naturally maintainable arrangements and help to progress to a low carbon economy while meeting the difficulties of expanding populace in such regions.
Big data & the Internet of things:
Cisco has estimated that more than 50 billion devices will be connected to the Internet of Things by 2020 where the potential to access and analyse an ever-expanding volume of data will open many ventures for the masses. Modifications and Advancements in the management and control of such large databases have evolved from relational database technologies to distributed Not only SQL (NoSQL) database technologies such as Cassandra and MongoDB due to scalable components and flexible attributes.
Existing Concept and Applications:
The increased digital facet of a smart city also showcases possibilities of security infringements. There are various potential threats faced in various sectors like in smart electric grids, domestic or commercial building automation systems and data storage infrastructure .
Transportation energy and Electric mobility:
The potential impact of ICT in the Transport sector has been emerging since the last decade particularly with respect to infrastructure and services where in specific challenges such as congestion management and parking space utilization have been dealt with utmost importance .
Integration of renewable and technological systems:
Owing to the increasing population densities posing increasing demands on urban environment systems there is a growing need for efficient integration of supplies and redistributing demands through renewable energy manifestations and intelligent management  which have recorded reduced costs, for example, solar energy installation recorded a drop of up to 50% between 2010 and 2015 alone which ensures long term environmental benefits in urban built form landscape.
Diversity in fuel mechanisms:
Apart from EVs, the capability to involve various energy supplies can utilize eco-friendly solutions for fuel to be introduced more tactfully into the transport sector. In  for example, ethanol used in multi energy based transport system reduced over 40% transportation costs.
Coordination, control and operation:
Design and Analytical understanding is further followed by operations and real time monitoring of multiple interconnected energy systems with optimal decision making regarding software and control systems. Several approaches for an amalgamated version of generation and distribution systems with adequate storage options are published like energy service supply systems, basic units, micro electricity based grids and hybrid energy hubs which have multiple energy systems. There exist several case studies that highlight the short term and long term benefits of suitable amalgamated approaches (e.g. a combination of Photo-voltaic (PV), Solar thermal and hydro produced 46% lower emissions than a PV-biomass combination) .
Citizen Engagement and Participation:
Data can be passively obtained from potential users by soft-sensing or crowd-sensing technologies through the sensors in the phones or other devices to identify the movement flow and travel patterns in and around the city. However, in an Indian Scenario, people are reluctant to the usage or exploration of such technologies. There is a need for Awareness and involvement of people in the working typologies for Intelligent Energy System .
Identification of Faults and further diagnosis:
In the presence of massive volumes of data for accurate technical incorporations, energy systems (like HVAC) often behave in an abrupt manner showing disruptions when compared with their natural operation phenomena which is a result of server issues or component failures. Many examples for Fault Detection and Diagnosis (FDD) have been discussed with various approaches as identified from processed history (measured database models), quantified techniques (detailed physical models), and qualitative understanding (professionally designed rules) . A variety of statistical and smart machine learning techniques have been previously analysed to study data-enhanced strategies like Principal Component Analysis (PCA)  to detect any kind of anomaly between variables under consideration, ANNs to classify faults based on evidences from historical data and fuzzy logic to incorporate human induced variables into classification procedure.
Real world barriers and further learnings:
Existing literature base has well established the tools and techniques, efficiency applications and forth coming opportunities of intelligent energy systems. However, the real-world incorporations and time based implementations in small scale pilot projects or large scale city boundaries require ample research to sail through practical hindrances on site. Some UK-based Future Cities with smart integrated energy solutions are discussed in . As far as real-world barriers are concerned, efficiency in management of smart energy systems is often affected by variables such as population density, mobility pattern, urban structure, economic development, industrial existence, historical importance, cultural priorities, political structures, etc.
Broadening the scope:
Smart energy systems cater to a multitude of aspects and agencies dealing with the same. However certain challenges and hindrances exist when the open access to data or sharing of information to analyse the issues comes into the scope of work. In  for example, the importance of various typologies of data (personal or impersonal) and the overall purpose and outcomes from the data are highlighted. Also, confidentiality of data is to be understood while using the same for necessary applications. Simultaneously, advanced approaches for smart resolution of issues are discussed. Approaches for secured maintenance of trading documents and policies are discussed in .
Global Case Studies with inferences:
In Austria, the OIB-standard is predominantly followed as a regulatory energy standard, set by the Austrian Institute of Construction Engineering . In some of the Austrian cities, the authorities are putting great efforts in reducing maximum energy consumption to reach EU regulation goals within the next few years for which the Austrian Low Energy Building Standard (OIB-standard) and the Nearly Zero Emission Buildings Standard (nZEB or NZE-standard) are followed ardently. Improvisations to save energy in buildings can be in the form of service level benchmarking of energy efficiency standards like optimised insulation building retrofit .
Innovative approaches with respect to intelligent energy systems include use of electricity as a renewable energy source, Heat energy and storage, heat integration of industrial waste and solar thermal energy in supply networks which are some of the major aspects of advancements in smart energy incorporations. The case study of Reininghaus District has been a pioneer in the research sector owing to the technologically advanced interventions as discussed in . Massive amount of modern and sustainable interventions have been applied for the provision of heating, cooling and electricity for the Reininghaus District. One of the interventions was the use of Low-temperature waste heat from an industrial source which provided to be the input to a large heat pump at the other end that resulted in the increase of temperature required for ambient residential heating simultaneously leading to the distribution of hot water through the connected main grids for residential usage.
Figure 1. : Optimal Technology System adopted in the Reininghaus district with centralized/decentralized systems 
For the optimization of district heating networks in California, a modelling technique was developed by Shaffer et. al (2018). The paper elaborates on the University of California campus as a selected case study for the several hybrid measures undertaken to make it energy efficient like fully functional microgrid systems with adequate capacities, large effective resources of on-site solar photovoltaic panels, zero-emission battery operated and electric buses with greater bus fleet sizes, integrated efforts to study the processes involving decarbonization through research based projects, modelling techniques, like demonstration of heat to gas technology for pipeline injection, smart charging infrastructure through microgrid technologies, etc.
Figure 2. District heating network, Irvine microgrid 
In the past decade, Deployment of these programs resulted in the achievement of 10% reduced energy for a population size of 50000, although 93,000 m2 area of building space was added to the microgrid .
Figure 3. Various Energy Systems deployed in the UCI Campus, Irvine microgrid 
Department of Energy with an ambitious target of achieving reduced on campus energy consumption by 20% by the financial year 2020. Efficient Energy management ideas in the form of small scale demonstration projects through advanced modelling techniques in the lab spaces are also undertaken.
The southern Cameroons is another example where a multitude of energy systems are taken into several permutations and combinations to come with solutions for reduction in carbon emissions. Nine hybrid systems which include Solar Photovoltaic (PV) module, wind turbine, micro-hydro turbine, diesel generator, battery, charge controllers, and inverter are considered in the study . These comparisons were then undertaken through a multi criteria decision-making approach to select the best systems with the targets as minimum renewable fraction of 40%, annual capacity shortage of 2%, system operating reserve of 10%, and with 10% each as the percentage of solar and wind output, A maximum renewable energy usage threshold of 40% is used.
The case area of Oregon is another case study which is in the planning stage where the energy systems of Solar, Wind and waves are planned to be incorporated for deploying efficient solutions to harness and use energy . The technologies of wave energy devices, wind turbine and photovoltaic modules are thought to be incorporated for the sustainable harnessing and management of
Figure 4. Comparative Study of Case areas taken
The growth of trends in Renewable Energy Resources (RES) has been rapid and emerging in the past few years which not only puts forward key challenges for power system operators to facilitate the same but simultaneously has enabled to bring about quick transformation and modifications in the energy systems. However, Energy Demand Response requires highly complex tasks to be performed with large-scale knowledge of data at ones disposal from different agencies along with adequate real time monitoring and decision making where Artificial Intelligence (AI) and Machine Learning (ML) have a key intervention to promote proper manifestation and apt functioning of intelligent energy systems. Siano  investigated regarding the key attributes and subsequent outcomes of Demand Response corresponding to smart grid mechanisms, smart and reliable technologies, adequate control, monitoring and management of information and communication technology which proved to be beneficial. Haider et al.  focused on the trend based developments of Artificial intelligence for Energy Demand Response, load scheduling techniques and ICT.
Figure 5.Decadal Evolution of Intelligent methods used for Energy systems Demand Response
W. Tushar et al.  discuss in relation to a concept of possible approaches of Demand Responsive energy systems to optimize a smart community that is composed of a substantially large cluster of residential units. There contributions lay emphasis on Distributed Energy resources which are currently in consideration owing to their capability in reducing GHG emissions and electricity bills. They reduce the dependency and load on the main electricity grids by deploying themselves as smart grid energy systems, consequently, lowering purchase cost of electricity. Owing to the benefits of distributed energy resources, the paper highlights on the modern approach of an energy management scheme for a community consisting of a large number of residential units and a shared facility controller depicting how both entities can mutually benefit, by energy trading, utility sharing and minimizing total cost of operations. The abrupt generation of electricity in distribution network has a negative impact on the overall power supply system if not monitored or controlled. The operation of adequate distribution network for Renewable energy sources required optimized standards to cater to the emission requirements and energy manifestations. Owing to the recent advancements in the fields of Energy management technologies for sustainable usage, B. Olek, and M. Wierzbowski  discuss regarding comprehensive energy management approaches by taking smart devices of Distributed energy systems, adequate storage systems with flexible loads into account. Also, nonlinear programming is done to achieve overall optimization along with application of Local Energy Balancing and Ancillary Services which are novel approaches that highlight technical implementation of LV distribution system by making use of the economic rules set according to market standards.
Existing Scenario in Indian Context:
Smart Grid and Micro Grid Scenario:
Smart Grids and Micro grids infrastructure have evolved in Indian states owing to their potential in reduction of carbon emissions. The Punjab State Power Corporation Limited (PSPCL) has issued a tender contract regarding installation of smart meters, advanced electricity metering infrastructure (AMI) systems, and communication infrastructure with a network platform forming a smart grid in Ludhiana. Similarly, Rajasthan Electronics Instruments Limited, a joint venture between the Government of India and the Government of Rajasthan, also issued a notice inviting tender for 700 energy meters in Jaipur to facilitate the installation, monitoring and control of smart grid technology for the sustainable energy incorporation in the state. In 2019, IIT Kanpur showed interest and involvement for three smart grid field pilots combining renewable sources (solar and biomass) and storage (Lithium-ion and flow batteries). This project was an initiative on intelligent energy systems called as U.S.-India Collaborative for Smart Distribution System with Storage (UI-ASSIST). Similarly, Sweden and India recently announced the India-Sweden collaborative industrial research and development program at the India Smart Utilities Week. BSES Yamuna Power Limited (BYPL) is commissioning four solar photovoltaic (PV) micro grids in East Delhi as a potential pilot project setting a spectacular milestone in an urban metropolitan setting. This pilot project involves clustered solar PV projects of sizes between 5 kW and 7 kW along with battery energy storage between 7-10 kWh.
Renewable energy-based microgrid or mini grid energy systems prove to be extremely beneficial for India. Owing to the shortage of electrical settings in rural areas, it can help the country facilitate the energy requirements to its rural population which is ecofriendly, economic and a sustainable option. Several Government-run electrification programs like the Pradhan Mantri Sahaj Bijli Har Ghar Yojana (SAUBHAGYA) to electrify all willing households in the country (24*7 Power to All), Deen Dayal Upadhyay Gram Jyoti Yojana (DDUGJY), and Unnat Jyoti by Affordable LEDs for All (UJALA), are some of the policies which could further surge to increase electricity demand simultaneously addressing the increasing number of households getting connected to the intelligent energy grids.
Electrical Vehicle Scenario:
In August 2020, the government introduced the New Delhi Electric Vehicle Policy, 2020, intending to improve and establish a strong demand for electric vehicles in the national capital region. The new policy imposed several incentives like tax waivers, adequate charging and swapping infrastructure establishment, battery cycling ecosystem, Public bike sharing amenities thus targeting to create a non-lapsable State EV Fund. Several financial incentives for EV buyers were also facilitated by the government. The policy highlights that e-rickshaws, electric two-wheelers, and e-freight vehicles will receive incentives of â¹30,000. Simultaneously, purchasers of electric cars will receive financial incentives ranging from â¹10,000 to â¹150,000. The policy empowers the use and adoption of battery operated vehicles targeting to reach 25% of new electric vehicle registrations by 2024. The policy also focuses to strengthen the electric charging infrastructure to facilitate the ease of movement and utilization of electric vehicles. India’s electric two-wheeler industry is reviving as the Society of Manufacturers of Electric Vehicles (SMEV) suggests. In April, SMEV publicly said that there has been an increase in the purchase of electric vehicles by 20% in 2019-20.
Mercom India tracks the current status of Electric vehicles where they have said, that about 2544 units of high-speed electric two-wheelers (E-2W) stand registered in September 2020, a 72% year-on-year increase compared to 1,473 units sold in the same month last year. The Solar Energy Corporation of India (SECI) has floated interest to empanel agencies so as to deliberately attract business opportunities, market ventures and encourage more demand in the segment of electric and transformative mobility. This interest from the SECI was issued to help India achieve its goal of increasing the overall share of electric vehicles by 30% along with the installation of proper and adequate charging infrastructure and other ancillary services. All these positive responses to the utilization and adoption of electric mobility has come into lime light owing to the government adoption of phase two of the Faster Adoption and Manufacturing of Electric Vehicles (FAME)-II scheme for all targeted and approved electric vehicle models across India. The next objective of the government is to evaluate the economic benefits of these prevailing opportunities and provide for the suitable implementation of the same.
Wind Energy Scenario
Wind energy has been harnessed over the years as a renewable means of energy provision. Recently, The Joint Electricity Regulatory Commission (JERC) has approved a tariff of â¹2.83/kWh and a trading margin of â¹0.07/kWh for the procurement of 40 MW of wind power between Chandigarh and the Solar Energy Corporation of India (SECI) along with an additional incorporation of 1,200 MW interstate transmission system connected wind projects (Tranche VI). Back in May, the JERC announced generic tariffs for solar, wind, and small hydro projects that applied to Goa, and union territories of Andaman & Nicobar Islands, Lakshadweep Islands, Puducherry, Daman & Diu, Dadra & Nagar Haveli, and Chandigarh. Similarly, The Maharashtra Electricity Regulatory Commission (MERC) has approved the energy purchase agreement (EPA) for wind projects with expired EPAs. With around 7,600 km of coastline at its disposal, the Ministry of New and Renewable Energy (MNRE) set an enormous target of 5 GW of offshore wind power by 2022 and 30 GW by 2030. The GWEC report has applauded the incorporations done by Tamil Nadu, since it has garnered more interest among Wind energy generators. Since 2016, Tamil Nadu has been the leading wind installer in the country. As reported previously by Mercom, Tamil Nadu has nearly 9.3 GW of cumulative wind installations, representing a 25% share of the total installed capacity in India as of Q1 2020. Wind power installations in India reached 2.07 GW in the financial year (FY) 2019-20, a 31% increase as compared to 1.58 GW in the FY 2018-19. Wind represents 10.1% of the total installed power capacity in India as of Q1 2020. Mercom has also stated that the cumulative wind power installations amount to 37.7 GW as of March 2020.
Solar Energy Scenario
Various agencies in India have shown a solar energy implementation response amounting to 578.19 MW, which are in the range of 500 kW to 4 MW. The Gujarat government has taken several measures to encourage and facilitate the adoption of clean energy projects in the state. In September last year, the Gujarat government relaxed the state’s solar policy to allow micro, small, and medium enterprises to install solar projects that are more than 100% of their sanctioned load or contract demand. Mercom India has researched; Gujarat has far installed approximately 2.4 GW of large-scale solar projects while ~2.2 GW of projects is currently in the pipeline.
The Eastern Coalfields Limited (ECL) issued a notice inviting tender to set up 1,415 kW of rooftop solar systems at 11 of its premises spread across 26 locations in West Bengal and Jharkhand. According to Mercom India, Jharkhand currently has only 20 MW of rooftop solar projects that are operating and currently being managed. On the other hand, West Bengal has about 47 MW of rooftop solar projects in operation, as of August 2020. In November 2019, Coal India Limited had launched an interest to set up a potentially large solar pilot project of up to 100 MW in Chhattisgarh for consumption to achieve its target as set forth by the state government. Recently, Karnataka’s Tumkur Smart City issued a potential request for encouraging the installment of 1.2 MW of rooftop solar systems on the government buildings in the city.
Smart Metering Scenario
The ongoing corona virus crisis and the poor financial and infrastructural performance of power distribution companies have focused that power sector needs a serious involvement of smart energy incorporations of which smart meters need to be an important part of the solution. A recent report by the Energy Efficiency Services Limited (EESL), the agency responsible for the implementation of smart meters across the country, showed that all states where smart meters were installed had good results. There has been an average increase in billing of nearly 25% across India. In the New Delhi Municipal Council (NDMC) area of the national capital, with a billing efficiency of over 99%, overall revenue has gone up by â¹500 per month per meter.
Aside from bringing in additional revenue to Distribution Companies, smart meters can also help consumers monitor and control their consumption of electricity to facilitate savings on electricity bills. Saurabh Kumar, Managing Director at EESL stated that Last year’s billing efficiency was 83%, signifying that 17% of electricity was not accounted at all. Total power consumption in the country was 1.3 trillion units then, and 17% of that would be about 220 billion units. Highlighting a total loss of over â¹1.1 trillion which is significantly more than the â¹900 billion package as announced by the government for smart metering. This stresses on the emerging need to account for the entire electricity consumption owing to administer the losses in the form of financial perspective.
India aims, by 2030, to reduce the emissions intensity of its gross domestic product (GDP) by 33–35 percent compared to the 2005 level; achieve 40 percent cumulative installed capacity for electric power generation from non-fossil fuel energy, through transfer of technology and low-cost international finance, including support from the Green Climate Fund (GCF); and create an additional carbon sink of 2.5–3 billion tonnes of CO2 equivalent through additional forest and tree cover. The government has announced ambitious plans to achieve 227 GW of renewable energy capacity addition by 2022.
Some of the challenges to be addressed to achieve the targets as set for the Energy systems are as follows:
Infrastructure up gradation, especially in India’s power sector is urgently needed. The outdated electricity grids lead to high losses and frequent outages with shutdowns due to overloading of short circuiting and similar issues. This is also enhanced by the issues pertaining to the current technology to communicate problems in real time in a smaller interval of time directly to the monitoring agencies or departments.
Creation of a national smart energy market should be of primary focus that is also supported by government policies and regulatory frameworks at specific intervals of time. It is also critical to bring India’s 29 states at a cumulative front with similar federal intentions. There are currently no common standards for open energy market to enable trading energy between states, or facilitate the track records for different states.
Government stability is a major question to ask in the Indian Scenario. Much of India’s progress in the domain of intelligent energy systems has been driven by Prime Minister Modi’s commitment to clean power. With the government getting re-elected for another five-year term, the sector is expected to maintain momentum in the near future.
Policy certainty and frameworks can maximize the potential of India’s outreach for facilitation of renewable technologies. For example, much has been speculated about India’s goals for batteries to maximize renewables, but no incentives or regulations have been finalized to support storage.
The financial stress of utilities, particularly distribution companies, limits their ability to invest in critical infrastructure updates and digital grid capabilities or explore alternative business streams. This funding challenge will need to be addressed, including through tariff reforms that bring the cost of electricity in line with actual costs.
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Nandini Ghose: Nandini Ghose is an Architect Transport Planner from Odisha, India. She completed Masters in Transport and Infrastructure Planning from School of Planning and Architecture, Vijayawada. She has over 2 years of experience in Architecture and Research. She is currently working for AIMAN Consultants, Lucknow, in the domain of Transport Planning and Research. Her interests lie in the segments of Public Transport, Energy Efficient Transport and Electric Mobility.
Rajiv Menon: Rajiv Menon K is an Urban Environmental planner from Kerala, India. He
completed Masters in Environmental Planning and Management from School of
Planning and Architecture, Vijayawada. He has worked in the field of
planning for almost 3 years in different parts of India. His areas of interest are
related to sustainability and smart urban areas.