The role of smart cities in meeting future energy demand
Global population and urbanization are increasing at a rapid pace. According to UN reports, 54% of world’s population was urban in 2014 and this figure is expected to be 66% by 2050. Global energy demand is expected to follow a similar trend and increase rapidly over the next few decades. Moderate UN scenarios suggest that if current population and consumption trends continue, by the 2030s, we will need the equivalent of two Earths to support us.
Energy is the most important driver of economic growth and as the world moves towards urbanization, the demand for energy is ever increasing in the cities. This provides us with both a challenge and an opportunity to decide the future course of our cities and more importantly the quality of life of citizens of the future. We need to ensure smart sustainable cities for our future generations.
When we hear or read about smart cities, it is mostly about technology, connectivity, cloud, big data, automation and controls, etc., a lot like sci-fi movies. But cities of tomorrow will require much more than these because the focus is not only on technological advancements but to make the cities resilient to climate change and more sustainable with long term planning. Moreover the cities need to provide a healthy and comfortable environment for the citizens. This includes focus on providing essential resources, smart city planning, effective transport system, safety and security of citizens and speedy governance.
Availability of essential resources will be a challenge owing to rapid growth of cities. So, smart and sustainable infrastructure design at city level is necessary to ensure effective distribution and management of various services. Buildings are the most visible elements of cities. They also contribute to one third of the global Greenhouse Gas emissions. People spend most of their time in buildings and therefore buildings have a major impact on the health and productivity of occupants.
While capacity addition is required to meet the growing energy demand of cities, there will be two sources of energy that will play a key role in future. The first source is energy efficiency in existing infrastructure and the second source is from renewables like solar and wind energy. Globally, many governments and corporates are embracing renewables to reduce their carbon footprint and move towards clean energy sources like wind and solar. But there is a great potential source of energy in cities that is largely untapped – energy efficiency. Energy efficiency can play a major role in freeing up energy demand from existing buildings/infrastructure and can also ensure the new buildings have minimized energy demand.
Energy efficiency can ensure optimum utilization of existing infrastructure such as the electrical systems. And energy efficiency can be achieved through smart designs and operations. We need our infrastructure to be smart so that resources like energy and water are delivered where necessary and utilized effectively with minimum wastage. This constitutes one of the characters of smart cities.
Smart designs and operations in buildings are among the most important aspects of smart cities to ensure energy efficiency as well as occupant comfort and productivity. It is possible to realize 30% to 60% lower energy demand through efficient buildings as compared to regular buildings. For example: A regular office building may consume about 200 kWh/sq. m. annually, whereas an efficient building consumes about 85 kWh/sq. m. annually. This means we would actually have 58% lower energy demand if the future buildings are efficient as compared to regular buildings.
Smart design of buildings involves a holistic approach to design from the initial concept stage. All stakeholders in building design need to work together and understand the interaction of different building systems to ensure an optimized and most efficient design. There are several tools available today that can quickly simulate a building and its components and give an indication of the energy consumption for different design options. This way, one can ensure the building has low energy demand.
Smart design of buildings also involves having the right monitoring and control equipment in the buildings to ensure essential data is captured and processed to optimize operations of equipment and to ensure comfort for occupants. Smart building systems (Building Automation Systems) are important to make the buildings respond to occupants. For example, various systems can be scheduled to operate during specified hours in a building. The heating and cooling systems in a building can be programmed to ramp up or ramp down based on the set temperature and/or based on occupants so as to maintain comfortable conditions. The lighting can come on/off based on occupancy sensors and daylight sensors. But what most people don’t realize is that the smart building systems can also play a major role in ensuring efficiency in the building systems through continuous monitoring of equipment and system operations data.
Smart operations involves utilizing the building systems only as much as required at any given point of time. This involves defining a set of algorithms to control different building systems such as lighting, heating/cooling and electrical systems so that the building is always running at highest efficiency. Smart operations involves monitoring the energy consumption of the building and the building systems closely so that operations can be optimized and the building energy demand is maintained at the lowest possible level.
Smart operations involves data driven operations where the building systems are driven by climatic data or occupant data so that the systems are operating accurately based on the need of the occupants. Data from operations are a wealth of information for future designs of buildings. Smart buildings provide actual data for designing new buildings so that building systems can have a more accurate basis for design.
There is a great opportunity in making our buildings smart and efficient. As a case study, Infosys, an IT giant in India has been able to reduce its per capita energy consumption by 49% from 2008 to 2016. Infosys campuses have office buildings, food courts, retail areas, sports facilities, guest houses, etc. While the company grew from 85000 employees to 200,000 employees in these eight years, the absolute energy consumption has increased by just 18% through smart efficient designs and operations. The peak electrical demand for an efficient office building is 35 watt/sq. m. whereas for a regular building it can be as high as 100 watt/sq. m. Data driven designs have helped Infosys achieve some of the most efficient buildings in the world today, and smart operations have ensured efficiencies are maintained and give valuable inputs for replacement of equipment or optimization of any systems.
Smart cities should have accurate monitoring of energy data so that measures can be implemented to reduce/manage energy demand dynamically. Smart cities are based on accurate feedback mechanism so that corrective action can be initiated. Smart systems like net metering will enable distributed generation and sharing of energy between different entities and thus reduce the overall capacity addition and investment. Smart cities need to have an effective communication mechanism between civic agencies and consumers so that demand side management measures can be deployed dynamically and effectively. With rapid urbanization and several cities to be built or expanded globally, smart cities will play a very important role in effective utilization of resources, and to ensure reliable energy access to all citizens.