# Techno-Economic Analysis of Flare Gas to Hydrogen: A Lean and Green Sustainability Approach
## 1 Introduction
### Flare Gas to Hydrogen Production: Lean and Green Potentials  
The quest for sustainable production in the oil and gas industry is gradually requiring methods that simultaneously improve operational efficiency and reduce the environmental impact of its activities. This means exploring approaches to transitioning from waste production to value-added production, which is the primary focus of lean and green integration [23; 24] as depicted in Figure 3. Lean focuses on reducing waste and inefficiencies in industrial operations, while green prioritizes environmental sustainability and lower carbon footprints [23; 25]. Lean and green practices can provide a solution when an industry poorly manages materials, leading to defects and waste that pollute the environment. This approach focuses on reducing non-value-added activities (muda) through lean and green tools, such as Value Stream Mapping, Sustainable Value Stream Mapping, Environmental Value Stream Mapping, and Kaizen, while also utilizing technologies that recycle waste into valuable products [26; 27]. With the recent policy initiatives addressing climate change, industries have been compelled to adopt sustainable practices and transition to cleaner production [28]. Lean and green integration has become increasingly important across various industries, providing a pathway to sustainable business practices. This transformative approach enhances operational efficiency while addressing environmental concerns [24; 29; 30]. Various industries, such as the automotive industry, the healthcare sector, and SMEs, have achieved significant success rates by adopting lean and green practices [27; 31; 32; 33]. Converting flare gas into hydrogen using technologies like SMR with CCS aligns with both philosophies by transforming pollutants into cleaner energy.  
The hydrogen economy represents a significant advancement in energy and a transition toward sustainability that integrates social and technical aspects [34]. This shift presents a unique opportunity for Nigeria to complement industrial development with environmental management. Furthermore, it is currently positioned to transform Nigeria's energy landscape while ensuring the protection of the planet for future generations. By implementing hydrogen technologies, especially SMR with CCS, the nation can significantly reduce its carbon emissions, enhance energy security, play a vital role in achieving global sustainability goals, and potentially its Nationally Determined Contribution (NDC) [35; 36]. This pathway of hydrogen production using SMR with CCS enables countries to leverage the current natural gas infrastructure while reducing carbon emissions. Despite the growing global momentum of the hydrogen economy and the abundant natural gas resources, Nigeria continues to lag due to inadequate investment [35]. To address this challenge, Nigeria must attract investments and facilitate the development of carbon capture and storage (CCS) infrastructure to produce cleaner hydrogen, and a strong commitment from the government is required. However, the government plans to invest USD 122 billion in diversifying the energy sector, which will reduce the country's dependence on the national grid while enhancing the stability and sustainability of Nigeria's energy infrastructure [37].  
Figure 3: Lean and green practice in the petroleum industry.