By V. Suresh Chairman, Indian Green Building Council (IGBC)
M. Anand Principal Counsellor, IGBC

Traditionally, till about two decades ago, appliances like lighting and ceiling fans were the major consumers of energy. Now, with changing lifestyles and growing necessities, the ambit of energy consuming appliances has grown significantly, covering TVs, refrigerators, mixer-grinders, geysers, exhaust fans, washing machines, air coolers, air conditioners, room heaters, computers, chimneys, dishwashers, microwave ovens… and the list continues to grow. This is resulting in increased use of resources and emissions.

The need of the hour is to address the growing energy consumption and focus on measures and approaches that are eco-friendly, energy efficient and encourage ecologically superior and economically viable concepts and technologies. Addressing this imperative, Indian Green Building Council (IGBC), a part of CII, launched an exclusive rating system focusing on the design of green homes in the year 2008. The rating system was designed to address national priorities and encourages designing homes that are a blend of India’s ancient architectural practices and modern technological innovations.

After one year of implementation, feedback from pilot projects was reviewed by the core committee, and its suggestions were incorporated in Version 1.0 of the rating system, launched in April 2009. Based on the feedback and learning from various projects that implemented the rating programme, Version 2.0 (Abridged Reference Guide) was launched in March 2012. The Abridged Reference Guide was further developed into an enhanced version as IGBC Green Homes Detailed Reference Guide, and launched in October 2013. With the experience gained over the years from the implemented projects and suggestions from stakeholders, Version 3.0 was launched in September 2019. The rating system is designed to suit Indian climatic conditions and residential construction practices.

IGBC has also launched the green building rating system covering Affordable Housing and Green Residential Society. One of the broad approaches to energy efficiency is to
optimise energy use by reducing energy demand in apartments and homes. Energy consumption can be substantially reduced by incorporating strategies that are economically viable with an attractive return on investment. Simple measures like orientation , harvesting day light , provisions for abundant ventilation, adopting passive measures and selecting energy efficient appliances can go a long way in enhancing the energy efficiency. The beneficiaries are the end users who can reap the benefits through the life of the building. This will also result in national benefits like reducing the dependence on fossil fuels and the associated pollution impacts. In India, sun is a source of abundant untapped energy. Roof tops may be used for generating hot water and also for generating renewable power with solar photovoltaic cells. Other sources of renewable on-site energy such as bio-gas digesters, and small wind systems using organic waste may also be explored.

Trending Green Features that a Smart Home Can Incorporate for Better Energy Efficiency

Ideally, a green home that is designed holistically would address key parameters, viz. site, water, energy, materials and resources, and indoor air quality. The smart home is an upgrade of a green home. Some of the key features include usage of certified green building materials and products in building construction to achieve low carbon footprint, zero waste, enhanced energy technologies, integration of renewable energy systems enabling net zero energy, water efficient landscape, ultralow flow water fixtures, usage of treated waste water for landscaping and flushing, bio-diversity and vegetation (ground, roof and vertical landscape) to address the heat island effect, innovation daylight strategies, LED lighting, lighting sensors, all technologies synced with smart phone.

The most trending green features that a smart home can incorporate for better energy efficiency include the following:

Daylighting
The best strategy to be energy efficient during the day time is to have access to natural light in the living spaces of a smart home. This again depends on how the building
is oriented and openings are designed. This strategy would give energy saving close to 60% in lighting alone, when it is integrated with lighting sensors. Lighting sensors work based on sensing the intensity of light falling on the sensor. These sensors form very important component of security, home control, energy efficiency, automated lighting control, and other helpful systems.

In spaces where daylighting from windows cannot penetrate, projects can make use of ‘light pipe’ innovation. The light pipe daylighting captures the sunlight from roof top and pipes it down through reflective tubing to the interior space. The diffuser at the end of tubing distributes the light in alldirections.

Energy Efficient Appliances
Use of LED lighting and star rated appliances can help reduce energy consumption to a great extent. Also, use of smart devices that regulate appliances and lights to minimize the amount of electricity they consume. Lighting and appliances are very similar to heating and cooling when it comes to energy waste. 

There may be times when we have left appliances or lights on in the home, and only realized after we come home from work, or even from a vacation. When we can control everything right from a smart phone, we do not have to worry about these types of problems.

Temperature Control
Computerized thermostats give us the power to minimize carbon footprint in several ways. One way is by regulating the temperature in the home through a mobile device. If you are on vacation and suddenly remember you forgot to adjust the thermostat of your air conditioner, you can do so right from your phone. If someone leaves a door open, a smart thermostat can shut off the air conditioning or heat automatically.

Going Net Zero
Projects achieving 20-30% energy savings by design over the energy benchmarks of Energy Conservation Building Code-R, and meeting the balance 70-80% through on-site renewable energy systems like solar photovoltaic and hybrid wind turbines to achieve self-sufficiency in energy requirement without depending on the main grid, become Net-Zero projects. In simple terms, the annual energy consumption of the project should be completely met through on-site renewable energy systems.

Metering & Monitoring
Sub-metering of areas like outdoor lighting, water pumping, EV charger, etc. can help analyse the electricity use pattern and further improve energy efficiency in a home. Building automation can help monitor the entire consumption pattern on one screen and makes it easier to access data and analysis. Smart water metering for every dwelling unit is the new trend in residential buildings.

Going the green and energy efficient way is indeed the need of the hour. Small but significant steps will make a difference to us, people around us and eventually to the global community. Going the green way should become a way of life to all of us.