By Dr. Vishal Garg (Associate Professor, and Head, Centre for IT in Building Science, IIIT Hyderabad),
India is facing an energy crisis where, at least 300 million of the country’s 1.25 billion people live without electricity. Another quarter-billion get intermittent power supply of about three to four hours a day. During the fiscal year 2014-15, the electricity generated in utility sector was 1,030.785 billion KWh (kilo watt hour), with a shortfall of 38.138 billion KWh (-3.6 per cent).
The peak load met was 141,180 MW, with a shortfall of requirement by 7,006 MW (-4.7 per cent). This deficit will increase in future due to rise in population and increase in the number of buildings, because they are one of the largest consumers of electricity.
Buildings use about 40 per cent of global energy, 25 per cent of global water, 40 per cent of global resources, and emit approximately a third of GHG (Green House Gases) emissions. Residential and commercial buildings consume approximately 60 per cent of the world’s electricity.
The global contribution from buildings towards energy consumption, both residential and commercial, has steadily increased reaching figures between 20 per cent and 40 per cent in developed countries, and has exceeded the other major sectors. Growth in population, increasing demand for building services and comfort levels, together with the rise in time spent inside buildings, assure the upward trend in energy demand will continue in future. For this reason, energy efficiency in buildings is today a prime objective for energy policy at regional, national and international levels.
India is developing at an unprecedented rate; our building sector is expected to increase five-fold from 2005 to 2050. India is at a unique stage where two thirds of the commercial and high rise residential structures that will exist in 2030 are yet to be built (as in 2010). This increase in number of buildings raises a very big problem of energy consumption. Since construction is yet to be done, it provides us a great opportunity to design and construct energy efficient buildings and reduce the building’s energy requirements. The building sector is estimated to be worth 10 per cent of global GDP (USD7.5 trillion) and employs 111 million people. The implications of such potential reduction should not be underestimated, as the scale of energy efficiency in buildings is large enough to influence energy security, climate preservation and public health on a national and global scale.
As a first step towards promoting energy efficiency in the building sector, the Energy Conservation Building Code (ECBC) was launched by Ministry of Power, Government of India in May 2007.
The ECBC was developed by an Expert Committee, set up by India’s Bureau of Energy Efficiency, with support and guidance from United States Agency for International Development (USAID) and significant inputs from various other stakeholders such as practicing architects, consultants, educational institutions and other government organizations.
The current code and surrounding policy systems encompass dynamic initiatives including efficiency requirements for most systems, bio-climatic design, commissioning of HVAC systems, mandatory renewable energy (solar hot water) requirements for specific building types and special efficiency requirements for public buildings.
Each building has its own site that presents unique set of opportunities and challenges. Each building owner or user has different requirements and climate and microclimate conditions can vary significantly among projects. Architects and engineers need flexibility in order to design buildings that address these diverse requirements.
The code provides this flexibility in a number of ways. Building components and systems have multiple options to comply with the code requirements. To use it, designers can choose the Prescriptive Method in which compliance can be achieved by meeting or exceeding the specific levels described for each individual element of the building systems or they can use the Whole building Performance Method where use of energy simulation software is necessary to show ECBC compliance. It is the right time to best utilise the building performance simulation tools to achieve better performing buildings and utilise the savings in energy to meet environment goals. Building simulation not only offers solutions to address building performance issues, but also helps during the construction process.
The use of computer based models (programs) is increasing to effectively aid in the design, operation, or management decision making process for construction and maintenance of buildings. It also lets us know how much a building consumes as per various national and international standards, which helps us set the bench mark of energy consumption for a particular building.
The successful implementation of the code requires development of compliance procedures in addition to building capacity of architects/designers/builders/contractors and government official in States and Urban and Local Bodies (ULBs). It is also dependent on availability of materials and equipment that meet or exceed performance specifications specified in ECBC. As of 2015, many states in India have made the ECBC mandatory and others have initiated the amendment/notification process for mandating the Code.
Source: The Hindu, 26th December-Focus on energy-efficient buildings
