Decarbonisation – The Transition to Sustainable Energy

Transitioning towards sustainable and low-carbon energy sources has become an imperative task. 

In the face of escalating climate change and the imperative to mitigate its far-reaching consequences, the global community finds itself at a pivotal juncture that demands an urgent and transformative response. At the heart of this imperative lies the critical need for decarbonization of our energy systems. As nations grapple with the escalating threats posed by greenhouse gas emissions and the ensuing environmental degradation, transitioning towards sustainable and low-carbon energy sources has become an imperative task. The Cover Story explores the pressing need for decarbonization, delving into the environmental, economic, and societal dimensions that underscore the urgency of embracing cleaner, more sustainable energy alternatives. The imperative for decarbonization emerges not merely as an environmental choice but as an ethical obligation, calling upon us to redefine our energy landscape and secure a sustainable future for generations to come. 

To begin with, it is essential to understand what is the present global energy mix, and the current pace of transition, given the fact that global energy consumption is still rising.

“According to the latest data from the International Energy Agency, the global energy mix of renewables was at 31 percent in 2023 and is projected to rise to 35 percent by 2025. Coal is the largest source of electricity globally, accounting for 36 percent. Natural gas is the second largest producer at 22 percent and hydropower is the third accounting for 11 percent. By 2030, renewable energy is projected to account for 50 percent of production with a majority of the growth from solar PV. Additionally, the world's electricity demand is projected to grow by 3.3 percent by 2025,” says Gaven Simon, Market Research Analyst, at ARC Advisory Group. Simon is a member of the industrial sustainability and energy transition team and has industry experience in Government. Prior to joining ARC, Gaven worked as a producer on two sustainability podcasts, where he helped develop engaging stories that featured emerging leaders in the clean energy and tech industry.

R P Gupta, Chairman & Managing Director, Solar Energy Corporation of India Limited (SECI), quotes the figures given by the World Energy Outlook 2023, where the current share of Renewables in the global electricity mix is said to be around 30%. The report estimates that on the basis of current policy settings of governments around the world, the share of renewables is expected to be 50% by 2030. Further, the report predicts that the share of fossil fuels in the global energy supply, which has been stuck for decades at around 80%, will decline to 73% by 2030, with global energy-related carbon dioxide (CO2) emissions peaking by 2025. Prior to joining SECI, Mr Gupta, a retired IAS Officer, worked in the Ministry of Environment, Forest & Climate Change as Secretary, Govt of India. His areas of expertise are energy, environment, climate change, decarbonization strategies, carbon market & trading, sustainability, resource efficiency and material recycling, forest, and wildlife. “As per recent news reports, 2023 saw more than 200 days where new daily global temperature records were set for the time of the year, including Sea surface temperatures. Therefore, stronger measures would be needed to keep alive the goal of limiting global warming to 1.5°C,” he says, with a measure of concern.

“The present global energy mix is characterized by a diverse range of sources, with fossil fuels, including coal, oil, and natural gas, retaining a significant share. Despite remarkable growth in renewable energy sources like hydropower and nuclear energy, the transition to a low-carbon energy system is an ongoing challenge. Fossil fuels remain abundant and cost-effective while existing infrastructure is heavily reliant on their utilization,” says Shrinjoy Bagchi, Deputy General Manager – Protection, Testing and Automation, Tata Power Delhi Distribution Limited, where he oversees the implementation of Digital Grid, Advanced Distribution Management System, Distribution Automation, Smart meter digital integration, large scale IoT deployment in utility landscape, OT Cybersecurity. “The journey towards a sustainable energy future faces obstacles, primarily due to the persistent rise in global energy demand. However, the implementation of renewable energy technologies has witnessed substantial advancements, notably in solar and wind power, driven by reduced costs and enhanced efficiency,” he adds.

Sunil David, Digital Technology Consultant, draws attention to the fact that the global energy mix is undergoing significant changes due to the increased focus on decarbonization and the adoption of renewable energy sources. However, fossil fuels are projected to remain a significant part of the energy mix for some time. Sunil is Advising and Consulting AI and IoT Startups that are aspiring for the next level of growth. Prior to that he has 28 years of experience in the IT and Telecom industry of which close to 20 years was with AT&T, one of the top Communication Service Providers of the World and a Global Fortune 100 Firm. “Over 60% of global electricity generated in 2023 was produced predominantly by fossil fuels, despite the ongoing aggressive roll-out of renewable energy sources in most major economies. Some of the major nations had sourced well over half of their electricity from fossil fuels in 2023, including the United States (59%), China (65%), India (75%), Japan (63%), Poland (73%) and Turkey (57%), according to data from a think tank Ember. The total demand for fossil fuels is expected to peak by 2030, with natural gas and oil continuing to play a core role for several decades. In contrast, renewables are expected to grow rapidly, driven partly by their cost competitiveness. By 2050, renewable energy sources are anticipated to provide between 65 and 85 percent of global power generation, with solar being the highest contributor, followed by wind,” he elaborates.

While hydropower and nuclear energy are traditional renewable power sources, what potential do solar, wind, hydrogen, and other renewable sources hold in the decarbonization process?

According to Gaven Simon, renewables are set to provide more than one-third of total electricity generation globally by early 2025. Low-emission sources including hydrogen, nuclear, wind, and solar are expected to cover all global demand growth over the next three years. “The forecast of renewables is expected to rise to 37 percent in 2026, largely supported by the expansion of cheaper solar PV. It is imperative that the expansion of renewable power generation should be matched with an accelerated investment in grids and technology to promote a smoother integration process,” he informs.

The amount of renewable energy capacity added to energy systems around the world grew by 50% in 2023, reaching almost 510 gigawatts (GW), with solar PV accounting for three-quarters of additions worldwide, according to IEA’s Renewables 2023. “Solar, wind, hydrogen, and other renewable energy sources play a crucial role in the decarbonization process and are integral components of efforts to combat climate change. Hydrogen, as an energy carrier, is becoming crucial for achieving decarbonization of hard-to-abate sectors. There is global momentum towards hydrogen in general, and green hydrogen – hydrogen produced through electrolysis of water using electricity from renewable sources – in particular,” says R P Gupta.

Shrinjoy Bagchi agrees that solar, wind, hydrogen, and emerging renewable energy sources, coupled with established contributors like hydropower and nuclear energy, represent a powerful force in the global decarbonization endeavor. Hydrogen, produced through renewable processes like electrolysis, emerges as a versatile and clean fuel applicable in transportation, industry, and power generation. “Collectively, these renewable sources significantly contribute to carbon emission reduction, enhance energy security, stimulate job creation, and drive economic prosperity. While hydropower and nuclear energy play critical roles, accelerating the utilization of solar, wind, hydrogen, and other renewables is paramount to meeting ambitious decarbonization goals. This approach ensures a sustainable and resilient energy future, addressing both current and future environmental challenges,” he asserts.

What are the emerging technologies that show the most promise for decarbonizing energy production and consumption? How can innovation and research be accelerated to advance clean energy technologies?

“As the global community faces the urgent need to decarbonize energy production and consumption, emerging technologies play a pivotal role in driving sustainable solutions. Several innovative approaches show great promise in achieving cleaner and more efficient energy systems,” says Manish Kumar Srivastava, Executive Director – Engineering, NTPC Limited. Associated with NTPC for over three and a half decades, Mr Srivastava has an illustrious experience of holding a spectrum of significant decision-making positions throughout his tenure and is one of the elitist brass of NTPC technocrats. Among Promising Technologies he lists Renewable Energy Sources – solar and wind power as key players in decarbonizing energy production, followed by Energy Storage. Breakthroughs in energy storage technologies, such as advanced batteries, mechanical energy storage systems, and grid-scale storage solutions, enhance the reliability of renewable sources and thermal power sources. Next-generation nuclear technologies, including small modular reactors (SMRs) and advanced fission designs, offer safer and more sustainable alternatives to traditional nuclear power. Implementing intelligent, interconnected grids facilitates real-time monitoring, demand response, and optimized energy distribution. Carbon Capture Utilisation and Storage (CCUS) technologies capture carbon dioxide emissions from industrial processes and power plants, preventing them from entering the atmosphere. Finally, switching to alternative fuel sources such as methanol, hydrogen, and ammonia, instead of relying on coal and natural gas, presents a viable alternative for decarbonizing energy production. “By prioritizing and accelerating research in renewable energy, energy storage, advanced nuclear, smart grids, alternate fuels, and carbon capture, coupled with strategic collaborative efforts and supportive policies, we can usher in a new era of sustainable, clean energy solutions. This multifaceted approach ensures that innovation becomes a driving force in mitigating climate change and building a greener, more resilient future,” he explains.

While in agreement in general about the emerging technologies for clean energy, Sunil David raises concerns on an important point – the use of AI to measure carbon emissions. “Carbon emissions measurement is extremely cumbersome. As per research, almost 40% of a sustainability professional’s time is spent collecting and cleaning data. Only 1 in 20 of those asked was 70% confident in terms of the accuracy of their emissions calculations. The use of AI can help lighten these loads,” he says. According to him, knowledge graphs that define relationships between various business activities and datasets, and natural language models can significantly speed up text processing and interrogation, enabling more accurate analysis at granularity that otherwise would not be feasible through human effort alone. As emissions reduction strategies turn into executable operational plans and interventions compete against each other for priority, a more granular analysis combined with business context becomes extremely critical. “Thus while using such intelligent, self-learning systems to tackle these challenges brings risks, especially with ‘black box’ modeling approaches where underlying sources and biases are unclear, the question is whether we can trust these systems to make environmental trade-offs for us, weighing climate change against other complex challenges such as plastic accumulated at ocean beds? Mitigating these risks will require leaning into issues that already make us uncomfortable as it demands more transparency. For AI to help make the world more sustainable, we really need to start with a comprehensive understanding of what we’re attempting to solve,” says David.

What solutions are available for energy storage to address the intermittent nature of renewable energy sources? How can energy distribution systems be optimized to reduce losses and increase efficiency?

“Currently, the most obvious solution to the intermittency issues with renewables is to store the energy when the wind is blowing and the sun is shining and use it once the energy is needed. Lithium-ion batteries are a good option but capacity issues and resource management are a point of contention. Grid-scale battery storage is a huge opportunity for growth and is in high demand,” opines Gaven Simon. Some other solutions that are still in the research and development stage include hydrogen storage, thermal storage, and mobile energy storage via electric vehicles. Hydrogen is poised to be a large opportunity for energy storage and can be produced by splitting water using renewable electricity via electrolysis. Then the hydrogen can be used as a fuel for various uses or stored for extended periods of time. “Additionally, energy distribution systems can be optimized to reduce losses with smart metering technology, updating reformers, and updating line capacity from 480 volts to 13,000 volts,” he adds.

“Grid-scale Energy Storage Systems (ESS) would help in smoothening the renewable generation output and thereby improving the power quality, helping grid stability, etc. There are several energy storage technologies available, broadly – mechanical, thermal, electrochemical, electrical and chemical storage systems, of which Battery Energy Storage System (BESS) and Pumped Storage Projects (PSP) have achieved commercial viability,” says R P Gupta. According to him, further technological advances are required for the evolution of energy storage systems, making them more efficient, cost-effective, and suitable for long-term grid-scale storage.

 “Apart from batteries and pumped hydro storage, flywheel energy storage, compressed air energy storage (CAES), and thermal energy storage, each contributing to storing surplus energy and releasing it during peak demand, can ensure a consistent and reliable energy supply,” says Shrinjoy Bagchi. “Optimising energy distribution systems is crucial for minimizing losses and enhancing efficiency. Smart grids, equipped with advanced sensors and communication technology, enable real-time monitoring and effective load balancing. Distributed generation, utilizing smaller-scale renewable plants, mitigates transmission losses. Demand response programs incentivize consumers to adjust their usage during peak hours, reducing overall grid load. High voltage direct current (HVDC) transmission decreases losses over long distances, and energy-efficient transformers improve total transmission efficiency. Resilient, efficient, and sustainable energy infrastructure can be achieved by integrating these storage options and optimizing distribution systems, he adds.

One of the important aspects of the entire debate over clean energy is supporting infrastructure. How can existing energy infrastructure be adapted or replaced to support decarbonization?

“Energy transition is a journey rather than a destination. The transition is not going to happen tomorrow. It will not take just one or two years to get there, but two to three decades. India has one of the youngest energy fleets in the world. Therefore, maintaining efficiency and reducing emissions from the existing infrastructure is going to play a key role in India’s path towards Net Zero Emissions (NZE),” says Manish Kumar Srivastava. IN his opinion, for a country like India, where per capita energy consumption is a fraction of the global average, ensuring energy security, sustainability and affordability is an equally important aspect. Meeting the energy needs of underprivileged populations with safe and sustainable energy access is the first and foremost consideration in India. Therefore, a comprehensive road map with a focus on the available resources and challenges for the Indian scenario is required for achieving the country's Net Zero commitments in a graded manner following a transition path.

“Adapting or replacing existing energy infrastructure to support decarbonization involves a multifaceted approach that targets different aspects of the energy system,” says Sunil David, who also mentions several strategies that could be followed:

• Upgrading Power Grids by leveraging technology – Smart Grids, Grid Resilience and Energy Storage Integration
• Renewable Energy Integration – Decommissioning Fossil Fuel Plants and Upgrading Existing Dams for Hydropower
• Enhancing Building Efficiency – Retrofitting Buildings and Smart Building Systems.

“In summary, the transition to a decarbonized energy infrastructure requires a comprehensive and coordinated approach, involving technological upgrades, policy support, and behavioral changes across various sectors of the economy,” he elaborates.

Finally, what policies and regulations are in place to support the decarbonization of the energy sector? Are there specific targets and timelines for achieving net-zero emissions?

Speaking about the United States opines Gaven Simon lists several policy measures in the last three years that witnessed a historic wave of investment from the federal government to help achieve its 100 percent 2050 net zero emission target. For example, in 2021, the Bipartisan Infrastructure Law was enacted which in total included $550 billion in investments for upgrading the country's infrastructure including roads, bridges, transmission lines, and EV charging networks. $73 billion was dedicated to investing in upgrading the US’s power infrastructure, which included plans for building thousands of miles of transmission lines to distribute renewable energy. Additionally, a year later in 2022 the Inflation Reduction Act was passed which included a historic $400 billion in investments for clean energy.

According to R P Gupta, the Government of India has announced a systematic long-term and short-term action plan under the Panchamrit action plan, and some of the constituents are reaching a non-fossil fuel energy capacity of 500 GW by 2030; fulfilling at least 50% energy requirements via renewable energy by 2030 among others. “There is a need for an integrated and coordinated approach for achieving decarbonization of the energy sector keeping in view the different primary sources of energy and their consumptions,” he says.

“India made a significant announcement at the 26th session of the United Nations Framework Convention on Climate Change (COP 26) in November 2021, declaring its commitment to achieving net-zero emissions by 2070. This pledge underscores India's acknowledgment of the global imperative to combat climate change and its dedication to transitioning towards a sustainable and low-carbon future,” says Shrinjoy Bagchi. The net-zero target for 2070 reflects India's commitment to balancing greenhouse gas emissions with equivalent removal measures, contributing to global efforts aimed at limiting the rise in temperatures. These collective commitments from nations globally highlight a shared commitment to mitigating climate change, reducing greenhouse gas emissions, and transitioning towards more sustainable and low-carbon economies. “Monitoring these commitments is essential, as they undergo periodic reviews and adjustments, with success contingent on the effective implementation of comprehensive policies and strategies across diverse sectors in each country,” he concludes.