Before delving into the world of green cloud computing, it's essential to understand the environmental challenges posed by traditional data centres. These facilities are power-hungry giants that consume vast amounts of electricity and are responsible for substantial carbon emissions. The environmental impact is significant, given the growing demand for data storage and processing.

The cloud has emerged as a game-changing solution to these challenges. Cloud computing involves the use of remote servers, which are typically more energy-efficient and eco-friendly than traditional data centres. Over the past decade, cloud computing has become a major technological breakthrough, transforming the way organisations operate^[1]. Cloud computing allows companies to obtain computing resources, software, and applications over the Internet on an as-needed basis, eliminating the need for expensive hardware and software investments^[2]. By migrating to the cloud, businesses can reduce their carbon emissions, energy consumption, and the physical space required for on-premises servers. Cloud computing has been widely adopted by a wide range of organisations, from large corporations to small and medium-sized enterprises (SMEs)^[3].

NCS is a recognised leader in cloud professional services (CPS) in the Asia Pacific region according to the IDC MarketScape assessment for 2023-2024 (Figure 1)^[4]. This survey revealed that 67% of enterprises in the region now have significant workload deployments on one or more public clouds, underscoring the growing importance of cloud to Enterprise IT. However, the same survey also revealed that enterprises in the region face critical challenges in their cloud journeys, including a failure to meet their desired performance and operational objectives, hybrid estate complexity, an inability to control costs, and a lack of necessary cloud-related skills, among others. This suggests that there is a lot of value that capable and experienced cloud professional services providers can bring to the cloud-centric migration and modernisation initiatives of enterprises^[4].

The increase in the popularity of cloud technology was due to the benefits it brings to individual consumers and companies. These benefits include flexibility, better disaster recovery, reduced need for investment in ICT resources, optimised collaboration between members of an organisation, and automatic software updates. Cloud computing is attractive to business owners based on its ability to dynamically increase the IT resources available to meet increases in the company’s activities and needs.

To meet the increasing demand for computing resources, cloud computing is continuously evolving to provide client companies with well-utilised options such as Software as a Service (SaaS), Platform as a Service (PaaS), Infrastructure as a Service (IaaS), and Container as a Service (CaaS)^[5]. These services enable customers to buy specific resources, pay only for their usage, and scale their services on-demand with pay-per-use models.

Figure 1. IDC MarketScape Asia/Pacific cloud professional services 2023-2024⁴

Organisations are expected to employ efficient and innovative technologies to maintain optimal levels of productivity within their ecosystems^[6]. Cloud computing offers a cost-effective and flexible solution to achieve these objectives by providing access to IT resources^[7]-[8]. The cloud computing market keeps expanding to achieve automation, streamline operations, reduce costs, and foster business growth.

A survey by Gartner found that 81% of organisations have adopted a multi-cloud IT strategy to use advanced capabilities across clouds, a number that is expected to increase and that confirms that shift towards digitalisation is a competitive imperative^[9]. As illustrated in Figure 2, use of cloud computing technologies is expected to increase at an impressive compound annual growth rate (CAGR) through the year 2028^[10]. This anticipated growth reflects the ongoing emphasis on integrating advanced technologies to enhance operational efficiency and support business expansion. Additionally, there has been a growing emphasis on sustainable growth in the business world^[11]. Organisations are increasingly striving to integrate sustainability into their operations and focusing not just on economic performance, but also on social and environmental factors^[12]-[13]. The emergence of cutting-edge technologies, such as cloud computing services, has accelerated this shift. To achieve a balance between economic and operational performance, organisations must improve their capabilities and promote sustainable performance^[14]. This is where the concept of green cloud computing comes into the picture. Green cloud computing is a concept that merges the power of cloud technology with eco-conscious initiatives. This innovative approach not only streamlines operations but also contributes to a greener, more sustainable future.

Figure 2. Forecasted CAGR growth of IT sector over the next five years¹⁰.

Interest in studying the influence of cloud computing on the environment is rising as the computing community becomes more aware of green computing. That focus is being driven by estimates that show that the ICT sector is currently responsible for approximately 4% of global CO2 emissions^[15], and that percentage could reach 14% by 2040, with data centres contributing to almost half of this growth^[15].

The development of green cloud computing is closely related to the evolution of green data centres because data centres are at the core of cloud computing. The interest in green cloud computing and green data centres is evident in the future strategies of leading providers such as Singapore’s Singtel. The design, build, and operation of green and sustainable infrastructure such as green data centres is a key pillar of Singtel’s vision (Figure 3)^[16].







Figure 3. Singtel’s vision on the development of sustainable next generation digital assets¹⁶

Singtel is scaling its regional data centre business, having gained a foothold in new markets beyond Singapore, including Indonesia and Thailand, where it is building a new generation of green, sustainable, and hyper-connected AI-ready data centres. Recently, Singtel also launched its new green and sustainable data centre brand, Nxera, to accelerate the company’s journey to net-zero emissions^[17]. Figure 4 shows Singtel’s different strategies to develop energy efficient green data centres across the region^[18].

Figure 4. Singtel’s different strategies to develop energy efficient green data centres across the region¹⁶.
 

Green data centres-where energy efficiency is maximised and CO2 emissions and e-waste are minimised, not only for ICT equipment, but across all environmental factors (building, lightning, cooling, etc.) are the basis for current and future green cloud computing. Green computing is not limited to minimising the energy consumption of computer devices. It also concerns the energy consumption of networks and cooling equipment and other environmental issues, such as CO2 emissions, waste management (e-waste), and the overall consumption of natural resources.

Today, we need green technology to solve energy and performance trade-offs. Proper distribution of workloads, and the maintenance of performance by providing access to services anywhere, anytime to users, is one of the cloud’s prime objectives. A key challenge for cloud service providers in balancing energy conservation with the performance guarantees that usually form a part of their service level agreements (SLA) with client companies. ^[18] Minimising energy usage may cause breaches of Service Level Agreements (SLA) and result in penalties to cloud service providers, and thus we should avoid any SLA violations when considering energy-efficiency systems^[18].