# Technology-Economy-Policy: Biochar in the Low-Carbon Energy Transition--A Review
## 1 Introduction  
Today, one of the most important challenges to overcome for humanity is global warming and its impact on climate and environmental change. Scientific research indicates that alterations induced by global warming adversely affect human health and the integrity of ecosystems, potentially jeopardizing the sustainability of life on Earth [1]. Due to the increase in the average temperature of the Earth's surface, global warming leads to adverse effects such as rising sea levels, storms and floods, the spread of infectious diseases, and changes in ecosystems, etc. [2]. It is well known that global warming is rooted in the accumulation of greenhouse gases (GHGs) in the atmosphere, which are mainly released as a result of human activities, particularly the burning of fossil fuels [3]. These changes have intensified considerably in recent decades, and they were accelerated by the Industrial Revolution [4]. Scientific studies point to coal mining as a major source of pollution and environmental degradation [5, 6, 7]. Scientists are intensively searching for solutions that will lead to halting growing climate change [8, 9]. Climate change isa complex intergovernmental global challenge affecting various elements of the ecological, environmental, socio-political, and socio-economic disciplines [10; 11; 12; 13]. The scale and complexity of environmental deterioration and climate change, especially with a growing global human population and unsustainable consumption patterns, requires disciplined and coordinated efforts to raise public awareness as well as to develop and implement effective responses. Due to industrialization, population growth, and rising living standards, it is virtually impossible to eliminate human activity; however, the consequences of inaction in the face of the above situation could prove disastrous. On 12 December 2015 in Paris, the United Nations Framework Convention on Climate Change (UNFCCC) reached an agreement to combat climate changes as well as to intensify and accelerate the measures and investment required for a sustainable low-carbon future. The main goal is to improve the global response to the threat of climate change by keeping the global temperature increase this century well below 2 \({}^{\circ}\)C, like pre-industrial levels, and to continue efforts to limit the temperature increase to 1.5 \({}^{\circ}\)C. In addition, the agreement aims to strengthen the capacity of nations to cope with the effects of climate change and align financial flows with low greenhouse gas emissions and climate-resilient pathways [14; 15; 16; 17]. Scientists report that immediate steps can increase the likelihood of offsetting climate change's destructive effects, but that its specific consequences are impossible to predict [18; 19]. According to scientists, the only currently available path against climate change and environmental degradation is the production and use of products based on renewable resources, which can minimize the concerns caused by carbon emissions. Indeed, the consumption of renewable resources, especially biomass, releases carbon dioxide, which is offset by the carbon absorbed by biomass as it grows, which is why it is considered \"carbon neutral\" [20]. As a result, today the transition to zero- and low-carbon products is crucial to mitigate the negative impact of carbon emissions and address the challenges caused by climate change [21]. Biochar appears to be a concrete tool for creating systems that can play an important role in mitigating climate change. The purpose of this review is to consolidate knowledge and assess the potential of biochar in carbon neutrality by application sector. In this study, we have highlighted the promising role of biochar in various fields, which can help achieve sustainability goals for carbon neutrality and a sustainable environment. With the policy of transitioning to low-carbon energy in mind, the paper attempts to juxtapose the opportunities and threats of biochar in the energy sector.