With growing affluence and changing lifestyle, building design and operations have become more energy-intensive. This has made energy regulations necessary to minimize energy impacts of building construction and operations and curb energy demand. As this is a very new area of governance, this sector is plagued with poor regulatory capacity for crafting of appropriate energy regulations and enforcement mechanisms.
According to the International Energy Agency’s India Energy Outlook 2015, the building sector accounts for more than 40% of total energy use in India. However, compared to the industrialized world, India’s energy consumption in households is still much lower and frugal. According to the World Bank’s database,only 75% of Indians had access to electricity in 2011. Only one-sixth these households are consuming over 100 kWh per month in comparison to 900 units per month by the average US household. But, the trend will change dramatically in India with changing lifestyles, incomes and electrification.
The future trend in energy consumption in the Indian building sector will be very different from that in the industrialized world.While, the Western world has reached a point of saturation,India has yet to build 60% of its building stock (to come up by 2030). In India, the upcoming structures need not become captive users of mechanical systems to maintain comfort conditions in buildings.
Traditionally, a combination of strategies including orientation of buildings, shading, organization of space etc. was applied to leverage local micro-climatic conditions – wind and sun – to achieve thermal comfort. But now it is possible to use technologies to artificially control and improve the thermal comfort of buildings. This is set to change the energy landscape in the building sector in India.
Under the mandate of the Energy Conservation Act of 2001, the BEE has crafted the Energy Conservation Building Code (ECBC) which defines norms for various aspects of a building– walls, roofs, lighting, heating,ventilation, air-conditioning and other motors and equipment used in building operation and maintenance.The voluntary code is meant for thermal management and efficient lighting to reduce energy use. It is aimed at commercial buildings with a minimum connected load of 100 KW or contract demand of 120 KVA. Project proponents are expected to follow the norms set by the code and demonstrate compliance for approval.
In addition to this, the BEE has also introduced star labelling for building operations and electrical appliances to reduce operational energy. Starrating grades buildings and appliances according to energy efficiency to encourage quicker uptake of energy efficient solutions. But, it is still not clear when the code will become mandatory.According to BEE, this demands adequate institutional, technical and enforcement capacity in cities. It is not yet clear how quickly such capacity can be scaled up in the states. Presently,some states have notified it, but its implementation is extremely limited.
The several gaps noticed in the code have raised larger issues of principles that should guide energy regulations and codes for buildings and how ECBC can be linked with them for the desired policy outcomes.When the ECBC was crafted, there was very limited experience and expertise in India. A lot of it was patterned along the lines of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE)standards for built environments. Now,there is a much deeper insight into India’s unique challenges, advantages and opportunities and the code will have to be optimised to reflect them.
How does the ECBC work?
There are two key approaches to comply with ECBC – prescriptive approach and a whole building performance (WBP) approach. In the prescriptive approach, the project proponent is expected to meet the norms prescribed for each aspect of the building (such as walls and roofs etc.). But this gives no sense of the overall energy performance of the building. The WBP method is more appropriate to help buildings set overall energy performance targets in terms of EPI when they are being designed. This has all the mandatory norms common to prescriptive approach, but also provides scope for using architectural interventions to demonstrate improvements in the energy performance of the building and reduction in energy intensity.
The ECBC is essentially a tool to set energy efficiency standards for appliances and equipment used in building operations and maintenance. The code also influences building design by prescribing standards for components of building envelope design and its thermal performance that have a direct impact on the energy efficiency of HVAC systems.
There are several critical gaps in the ECBC that can increase energy intensity of the building. For instance, ECBC does not cap the thermostat or temperature setting for designing of the HVAC systems based on Indian climatic and comfort conditions. This is a critical parameter, as with a drop of one-degree temperature from its setting the energy penalty can be as high as 3-10% depending on the conditions. Global best practices show that for most building typologies, temperature setting is mandated at 27-28oC plus/ minus one, taking into account the adaptive comfort conditions. Countries in Asia such as Japan, Sri Lanka, South Korea etc. have set the thermostat for the HVAC system. Test results by the Tokyo Electric Power Company indicate that raising the AC’s thermostat from 26oC to 28oC and using an electric fan in combination can reduce electricity consumption by up to 22%. Only special buildings like hospitals or labs can have lower settings taking into account special needs of preventing infection etc.
What is ECBC trying to achieve?
There is no clarity today about the current national baseline for energy performance in the building sector to understand how targets for future energy savings can be set and achieved. Traditional frugal lifestyle is fast getting replaced by the changing aspirations and modified expectations of comfort of the growing middle class. This can change the way buildings are designed and operated quite dramatically with huge energy penalties. But the Ministry of Power and the BEE have not set any energy savings goals for the sector to guide the use of the code. The BEE has not set any overall energy saving targets for the sector to be met in a time-bound manner.
ECBC, therefore, works in isolation from any such additional and overall energy saving and energy performance targets for the sector. It is not possible to verify and quantify improvements in energy performance of the new building stock over time to reach a stated performance target. The code, therefore, works on the assumption that the new stock could have been far worse in energy performance because of increased dependence on mechanical cooling and other comfort requirements; but by making them adopt energy-efficient technologies their individual baselines can be improved. Based on this principle, the BEE estimates that nationwide implementation of ECBC can yield savings of 1.7 billion kWh. But this does not indicate how the code can help push the average performance of the sector to meet specific saving and performance targets.
For instance, the BEE has so far given a very broad approximation of the current national average baseline of energy performance index (EPI) for standard commercial buildings to indicate the extent of energy use in the building stock. The baseline EPI is about 180-200. The ECBC user guide estimates that an ECBC compliant building will use 40-60% less energy than conventional buildings; the BEE claims that with ECBC compliance, the EPI can improve to 110-140. But these estimates are not backed by any primary survey or detailed impact assessment.
There is a strong concern that the overall baseline can worsen as there are no additional policies to incentivise reduction in air-conditioned spaces or need for mechanical cooling, the single most crucial parameter that will influence energy intensity of buildings. Two out of five sections of the ECBC code, the way it is designed, work only for buildings that are suitable to be fully air-conditioned; but they are applicable to all buildings having a connected load of 100 kW or more irrespective of their air-conditioning status. The code assumes all future commercial buildings will be 100% air-conditioned. It, therefore, aims to ensure rapid uptake of energy-efficient cooling and insulation systems and energy efficient appliances to cut additional energy guzzling.
Currently, most Indian residential buildings are not air-conditioned with only three per cent air-conditioner penetration in urban households. Also, unlike the cold countries of Europe and North America, India rarely employs centralized heating systems for winters. India’s per capita floor area is also very low. Therefore, on an average, a typical building in India inherently consumes far lower energy than its counterpart in USA.
Address Operational Energy
While the ECBC code is expected to influence the design and construction of buildings, the BEE has additionally introduced star rating of buildings to influence and curb energy use. Buildings are star rated according to the bandwidth of the energy use – the most efficient band gets the 5-star rank. However, there is scope for further improvement in the star rating process.
For instance, the BEE needs to stop discriminating between buildings based on air-conditioned area and set common but stringent standards.
A study by the World Business Council for Sustainable Development shows that people may increase usage after installing efficient lights but lose up to 12% of the expected energy savings by leaving them on longer. An efficient furnace loses up to 30% because people raise the thermostat. Consumption-based energy pricing and billing can make a difference. Global studies show that when tenants are billed for actual consumption, energy use for heating typically drops by 10 to 20%. Therefore, energy policies for the building sector in cities require a range of energy indicators – absolute total usage; per person per year; and per square meter per year need to be tracked as part of the regulatory programme for real results.
Sprucing Implementation Strategy
Even though ECBC has been around since 2007 it has not been implemented effectively on ground yet. State governments have initiated the administrative process for its implementation. Some have even notified and amended it to suit local conditions. But the implementing agencies have not yet developed adequate technical capacity to implement ECBC at a scale needed to make a difference.
Operational energy is a critical parameter that ultimately decides the actual energy savings in the building. It is important to develop some synergistic relationships between the designed EPI and the expected performance of the building.
The BEE is helping promote web-based tools for compliance checks; checklists of interventions necessary for compliance; and rules to support enforcement. This will require immense capacity building in urban local bodies. This will also require a strong cadre of independent ECBC-certified professionals for verification of design, construction and completion of buildings. While architects, builders and other building professionals need to fill in the knowledge gap which is hindering translation of an efficient building design into an energy prudent building in operations.
States like Rajasthan, Punjab, Haryana and Odisha, among others have already notified ECBC to begin implementation. Several of them are also taking steps to modify the ECBC to customise for local conditions and requirements. Punjab has gone ahead to bring large residential sectors within its zone. Rajasthan has included an additional clause that says that buildings with more than 1,000sqm of air-conditioned space will also require ECBC.
The implementation of ECBC and its reform will also require harmonisation of the code with several other rules, bye-laws and regulations, like the National Building Code, EIA and the green rating tools. Harmonisation of ECBC with NBC has already been carried out by including a chapter on “Approach to sustainability” which would be adopted in all future constructions in the country.