Presently all our resources and time are deployed to fight the Coronavirus which has already killed lakhs of people world over. With the successful invention of vaccines and medicines to fight the pandemic we may be able to mitigate its effects greatly (and perhaps completely) in the coming days. Once we are able to manoeuvre the pandemic decisively, there is another challenge needing our urgent attention, that is, climate change which may soon become a crisis if not tackled immediately.
Time has come to turn promise into reality
Many countries have pledged to reach net‐zero emissions by mid‐century or soon after. Now the time has come to narrow down the gap between rhetoric and action if we are to have a fighting chance of reaching net zero by 2050 and limiting the rise in global temperatures to 1.5 °C. Doing so requires nothing short of a total transformation of the energy systems that underpin our economies. We are in a critical year at the start of a critical decade for these efforts.
Special efforts needed to make buildings sector energy efficient
Buildings being one of the main energy guzzlers and also toughest sectors (especially in emerging economies like India) to reach the target need special efforts to ensure we reach the target by the scheduled year. According to International Energy Agency, in buildings, bans on new fossil fuel boilers need to start being introduced globally in 2025, driving up sales of electric heat pumps. Most of the old buildings and all new ones should comply with zero‐carbon‐ready building energy codes.
Vibrant building energy codes needed
Achieving decarbonisation of energy use in the building sector requires almost all existing buildings to undergo a single in‐depth retrofit by 2050 while the new constructions should meet stringent efficiency standards. In other words, we need to have a vibrant building energy codes covering new and existing buildings and also their strict enforcement by the local bodies. World over building energy codes are currently in existence or are under development in only 75 countries, and codes in around 40 of these countries are mandatory for both the residential and services sub‐sectors. According to IEA, if we have to meet the 2050 net zero deadline, its necessary that a comprehensive zero‐carbon‐ready building codes are implemented in all countries by 2030 at the latest.
Building floor area to increase by 75% by 2050
Meanwhile, according to IEA, floor area in the buildings sector worldwide is expected to increase 75% between 2020 and 2050, of which 80% is in emerging market and developing economies. According to some experts, in India nearly 70% structures needed are yet to be built and they are likely to be built in next ten years! Globally, floor area equivalent to the surface of the city of Paris is added every week through to 2050. Moreover, buildings in many advanced economies have long lifetimes and around half of the existing buildings stock will still be standing in 2050. Demand for appliances and cooling equipment continues to grow, especially in emerging market and developing economies where 650 million air conditioners are added by 2030 and another 2 billion by 2050 .
Decarbonisation in buildings largely depends upon energy efficiency and electrification. No new innovations are needed and transformation can be achieved through existing technologies like improved envelopes for new and existing buildings, heat pumps, energy‐efficient appliances, and bioclimatic and material‐efficient building design. According to IEA, “Digitalisation and smart controls enable efficiency gains that reduce emissions from the buildings sector by 350 Mt CO2 by 2050. Behaviour changes are also important in the NZE, with a reduction of almost 250 Mt CO2 in 2030 reflecting changes in temperature settings for space heating or reducing excessive hot water temperatures. Additional behaviour changes such as greater use of cold temperature clothes washing and line drying, facilitate the decarbonisation of electricity supply.“
10 million houses to be retrofitted annually
The target appears to be too ambitious especially in countries like India, which are still largely dependent upon fossil fuel for energy generation. To achieve the target, more than 85% of buildings need to comply with zero‐carbon‐ready building energy codes by 2050. Meanwhile, retrofit rates need to increase from less than 1% per year today (in India its almost nil) to about 2.5% per year by 2030 in advanced economies: this means that around 10 million dwellings are retrofitted every year. In emerging market and developing economies, building lifetimes are typically lower than in advanced economies, meaning that retrofit rates by 2030 in the NZE are lower, at around 2% per year. This requires the retrofitting of 20 million dwellings per year on average to 2030. Building envelope improvements in zero‐carbon‐ready retrofit and new buildings account for the majority of heating and cooling energy intensity reductions in the NZE, but heating and cooling technology also makes a significant contribution.
Slow start in India
If the statistics provided by Indian Green Building Council is an indication ‘Net Zero Buildings’ are making some headway in India. According to IGBC’s Annual Review report, till now, more than 10 corporates have committed to make their buildings Net Zero Energy in near future. About 1,55,984-sq.m of built-up area of different types of buildings including corporate offices, IT/ITES buildings, factory buildings and warehouse are in the process of implementing Net Zero Energy concept and 6 projects have already achieved the status of Net Zero Energy Buildings, says IGBC’s Annual Review report.
Both technical advances and government policies should be able to ensure that appliances and lighting consume less energy. In advanced economies, nearly 80% of the appliances and air conditioners used by 2025 will be the most energy efficient ones and this ratio will become 100% by 2050. Unlike advanced economies, emerging markets and developing economies will require several policy initiatives by the government in next ten years to achieve this target by 2050. The share of electricity in energy consumption in buildings is expected to rise from 33% in 2020 to around two‐thirds in 2050 in the NZE, with many buildings incorporating decentralised electricity generation using local solar PV panels, battery storage and EV chargers.
Thus, we have an uphill task ahead on which actions are needed on war footing. In fact, government decisions and policy actions are crucial for achieving these targets. Actions are needed on several fronts like energy codes and standards for buildings, fossil fuel phase out, use of low‐carbon gases, acceleration of retrofits and financial incentives to encourage investment in building sector energy transitions. This requires governments to act before 2025 to ensure that zero‐carbon‐ready compliant building energy codes are implemented by 2030 at the latest. Making zero‐carbon‐ready building retrofits a central pillar of economic recovery strategies in the post Covid environment is an ideal way to jumpstart progress towards a zero‐emissions building sector.