Transportation, industrial & commercial activities, buildings & infrastructures, water distribution, food production, entertainment, waste management or any other elements of life, most of those activities take place in or around cities which are on average responsible for 75% of a country’s Gross Domestic product (GDP) and therefore the main growth engines of world economy. And energy is the most significant element at the core to be able to execute all of those city functions.
It is helpful to view cities as organic systems that have their own metabolism. They consume about 75% of total global energy generation, but unfortunately also responsible for 80% of its greenhouse gas emissions. In this manner, smart cities will need to optimize their energy demand & consumptions by both of lowering resource usage and negative climate impacts while supporting larger populations and meeting citizens’ expectations for a better life quality.
Global energy demand will be doubled or even tripled by 2050 and 70% of the world’s population will be living in cities by that time. Therefore, the way we generate, distribute and consume energy is continuously changing and evolving.
All of those innovative approaches from energy generation to energy distribution and to energy management systems mainly exist to provide better sustainable solutions for a more demanding future.
As the world keeps urbanization, which will be so, cities will need to produce more with less and the energy is the most essential element to all city functions and services. It is just like a circulatory system of a human body which keeps it alive, but it is not so that easy to achieve efficiency because in a real economy, maintaining a reliable and secure energy supply, providing long term affordability and reducing environmental impacts such as green house emissions may create conflicts among these objectives. Beyond those challenges, cities will also need to establish appropriate regulatory frameworks and to design new business models for a sustainable energy market.
There can be lots of solutions for a resilient energy future of a smart city, but let’s categorize them into 5 critical elements; (I) Energy Supply: Renewables/alternative energy resources in the forms of large-scale biomass, wind, solar, hydro, tidal plants, algae-based biofuel and so on may help cities to meet growing energy demand by lowering carbon emissions.
According to the OPEC projections, $10 trillion should be invested in the oil and gas sector up until 2040 in order to meet the ever-growing global demand.
Most of decision makers do not want to invest those significant amount of money into the fossil sector for oil exploration and production only. Therefore, we are in the middle of a new global cycle and have been exposed to supply transformation in primary energy resources on a global scale. It accelerates cities to become smarter by cleaner, cheaper and more sustainable energy systems & technologies. Besides, converting 100% of its electrical energy to renewable resources among city administrations is adopted more as an ambitious goal to smart-up cities. City of Aspen (USA), Pingtung (China), Vancouver (Canada), Tshwane (South Africa), Jeju (South Korea) and Malmö (Sweden) are just some of those aspiring cities.
(II) Energy Storage: There is a consensus about the benefits of renewable energy resources. It is a crystal-clear fact. Nevertheless, renewables have a common deficiency at global scale. Electricity is consumed at the same time as it is generated, which means that the proper amount of electricity must always be provided to meet the varying demand at each hour. Any imbalance between supply and demand will damage the stability and quality (voltage and frequency) of the power supply.
Unfortunately, current renewable technologies are vulnerable in terms of providing stable energy and preventing imbalance.
Therefore, Electrical Energy Storage (“E-storage”) is one of the key technologies to encourage the usage of renewables. E-storage tech has four major benefits; i) It reduces electricity costs by storing electricity obtained at off-peak times when its price is lower, for use at peak times instead of electricity bought then at higher prices, ii) E-storage supports consumers when the power network failures occur due to the natural disasters and improve the reliability of the power supply, iii) It maintains and improves power quality, frequency and voltage iv) E-storage decreases technical power loss on the system in comparison to the conventional systems since they are located close to places where electricity is consumed.
(III) Smart Grids and Microgrids
A Smart Grid is an electrical grid which includes a variety of operational and energy measures including smart meters, smart appliances, renewable energy resources, and energy efficiency resources. It provides i) Realibility: Improve fault detection, allow self healing of the network without intervention of technicians, and reduce vulnerability to natural disasters or attacks ii) Flexibility in network topology: Classic grids are designed for one-way flow of electricity. However, if a local sub-network generates more power than it is consuming, the excess energy load and reverse flow can raise safety and reliability problems. A smart grid is designed to handle those situations and provides alternative electricity routes against blackouts through its multiple circular grid design iii) Efficiency: Smart grid technology provides better demand management, less redundancy on distribution systems, greater utilization of generators and lower energy prices. For example, turning-off air conditioners during short-term spikes in electricity prices, reducing the voltage if required on distribution lines and tracking alive energy consumption by advanced metering systems are some of them iv) Sustainability: The improved flexibility of a smart grid permits the usage of different renewable energy sources in a more efficient way because sudden fluctuations in distributed energy can be controlled more efficiently through the advance infrastructure technology v) Market-enabling: Smart grid allows for systematic communication between suppliers and consumers to take advantage of the changing energy prices.
Microgrids and minigrids are smaller and less-automated versions of smart-grid technology. They interconnect small, modular electricity-generation sources to low-voltage distribution systems, and some can be powered by a combination of petroleum-fueled generators, solar, wind and other sources.
Even the US Defense Department has begun to install and evaluate microgrids and minigrids for use on the battlefield and in domestic installations since they offer a range of positive outcomes that include less need for fuel, reduced noise and heat signatures, less maintenance, and a lighter force.
As a result, it provides energy security and saving up to 40%. In 2010, the Army deployed a 1-megawatt microgrid (called tactical microgrid) at Camp Sabalu-Harrison in Parwan, Afghanistan. Before the installation, the microgrid was tested for 3,000 hours by soldiers at the National Training Center at Fort Irwin in California’s Mojave Desert. When you consider the yearly military consumption of 600 million gallons (227,100 tonnes) of fuel oil in Afganistan and thousands of trucks on the road carrying those barrels, it can be understood in better way how it is effectual to reduce costs and to increase military energy security.
(IV) Data in Smart Cities: Information and Communication Technologies (ICT) can be deployed to provide more efficient energy usage through data analytics. Real time data contributes the analysis of behavioral shifts at early stages and help taking necessary precautions accordingly. For example, Simultaneously by visualizing decentralized heating planning data, energy consumptions, housing density data and policy indicators, a city administration can identify opportunities and use them to reduce future energy demand and carbon footprint without creating any disappointment on the local residents.
(V) Energy Reduction in Buildings: Buildings account for 40% of global energy consumption and 21% of carbon emissions. Significant amount of energy savings can be achieved through the combination of regulation, eco-friendly re-design of new buildings, energy saving technologies and smart interfaces.
For example, detailed monitoring and reporting of real time energy consumption of buildings can be designed through user friendly interfaces and gamified by various energy efficiency programs which are incentivized by local administrations.
Games and gamification can be used to motivate and support citizens’ behaviors in energy use to compete each other. Some sort of reward mechanisms such as badges, various incentives to use energy efficient technologies and customized price adjustment mechanisms accordingly can also be a significant and joyful solution for buildings.
BP Energy Outlook 2035 - 2015 edition
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