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Current Trends in Sustainability of Bitcoins and Related Blockchain Technology

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Current Trends in Sustainability of Bitcoins and Related Blockchain Technology sustainability Review Current Trends in Sustainability of Bitcoins and Related Blockchain Technology Pasquale Giungato 1,* ID , Roberto Rana 2, Angela Tarabella 3 and Caterina Tricase 2 1 Department of Chemistry, University of Bari, Bari 70125, Italy 2 Department of Economics, University of Foggia, Foggia 71121, Italy; [email protected] (R.R.); [email protected] (C.T.) 3 Department of Economics and Management, University of Pisa, Pisa 56126, Italy; [email protected] * Correspondence: [email protected]; Tel.: +39-099-4725-234 Received: 26 October 2017; Accepted: 27 November 2017; Published: 30 November 2017 Abstract: Bitcoin is a digital currency based on a peer-to-peer payment system managed by an open source software and characterized by lower transaction costs, greater security and scalability than fiat money and no need of a central bank. Despite criticisms about illegal uses and social consequences, it is attracting the interest of the scientific community. The purpose of this work is to define and evaluate the current trends of the literature concerned with the sustainability of bitcoin, considering the environmental impacts, social issues and economic aspects. From the analysis it emerges that the transition of the whole monetary system in the new cryptocurrency will result in an unacceptable amount of energy consumed to mine new bitcoins and to maintain the entire virtual monetary system, and probably bitcoin will remain a niche currency. Blockchain, which is the base for a distributed and democratically-sustained public ledger of the transactions, could foster new and challenging opportunities. Sharing the framework of medical data, energy generation and distribution in micro-grids at the citizen level, block-stack and new state-driven cryptocurrencies, may benefit from the wide spread of blockchain-based transactions. Under the perspective of its being a driver of social change, bitcoins and related blockchain technologies may overcome the issues highlighted by numerous detractors. Keywords: bitcoin; sustainability; monetary exchanges; digital currency; energy consumption 1. Introduction Since the introduction of the first IBM personal computer in 1975, and later in 1993 with the diffusion of the “internet”, technology entered homes and spread widely over the world as a new digital revolution that brought sophisticated and distant technologies within everyone’s reach, such as photo development, music listening and authoring, and home banking. The introduction of bitcoin in 2009 seems to represent a new starting revolution in the way we make money exchanges and value creation [1]. Bitcoin can be considered as the next stage in the process of money evolution: an electronic money in no way connected to the objects of the material world, with several advantages when compared to other forms of money [2]. Bitcoin is a digital currency based on a payment system that relies on a peer-to-peer network created as an open source program in 2008 and launched in 2009 by a developer named Satoshi Nakamoto, but this may be a pseudonym behind which another individual or group may hide. The creation and transfer of this virtual currency is made under cryptographic connections for this reason Bitcoin is also referred to as “cryptocurrency”. The mechanism of creation, distribution and maintenance is not managed by a central bank, but is decentralized in a worldwide community sharing a peer-to-peer connection and using a software that manage exchanges like a digital wallet. The transfer Sustainability 2017, 9, 2214; doi:10.3390/su9122214 www.mdpi.com/journal/sustainability Sustainability 2017, 9, 2214 2 of 11 of currency from one wallet to another is simply an exchange of digital bits without involving paper, coins, credit or debit cards, bank accounts, security accounts and no collateral. In addition, bitcoins rely on dedicated rigs of personal computers, mining for new coins through a series of tasks that require considerable computational power. Presently, although bitcoin is considered a currency that could overcome limits of the fiat money, there are some issues related to its sustainability. In this regard, bitcoins may be viewed from different angles: the economic, social and environmental points of view [3]. First, a precise definition of the sustainability of bitcoins is needed. We must consider that bitcoins are entities living in a different ecological ecosystem: the digital ecosystem. A digital ecosystem consists of all hardware devices, program files, and data files that the user needs and it shares with other users. The ecosystem as defined also includes the social elements which led to the creation and use of digital elements like bitcoins as no-material technological objects [4]. The digital resources we mentioned are more properly defined as “digital artifacts”, “entities that consist of strings of 0 and 1, which can be interpreted by technical devices, like computers, to provide some meaning” [5]. As bitcoins have an economic value it can be considered a “digital good” in which the computing capacity defines both the scarcity of the good and the raising of its economic value [6]. Indeed, bitcoin’s increasing value is due to its rocketing popularity in recent years. For instance, in 2009 there were fewer than 10,000 transactions in bitcoin, whereas by May of 2017 this number had exceeded 300,000. Consequently, the economic value of bitcoin in May 2017 had reached even more than 5000 United States dollars (USD) [7]. The economic standpoint relies on the ingenious mechanism of transaction in which there is not a third party which guarantees an exchange but the transaction happens directly between the exchangers and the system provides a cryptographic proof of the transaction. Moreover, bitcoin creation is not indefinite as the number of bitcoins is limited to a definite number, generating an inflation due to currency scarcity and making it a store of intrinsic value as gold and silver. At the present day about 25 new bitcoins are generated every ten minutes, and that number will progressively be halved every four years [8]. Bitcoin mining is increasingly difficult requiring both more people or PCs and complex algorithms: at the present only the most powerful computational networks, with several central processing units working together, are able to create additional coins. Secondly according to some authors, the bitcoin protocol as it was planned, consumes increasing amounts of energy and natural resources, as well as being used by illegal activities [9]. In this context, the present work is intended to focus on the current trends in exploring the sustainability concepts related to bitcoin diffusion. In particular, because the literature has focused basically on economic aspects, the present review will consider the environmental and social sustainability of this cryptocurrency and its future trends. 2. Materials and Methods The literature review was conducted by using as the keywords for online research the words “bitcoin”, “digital currency”, “cryptocurrency” and “virtual currency”, with “sustainability” in the databases Scopus, ISI Web of Science and Google Scholar (Table1). Table 1. Number of papers that considers the terms “bitcoin”, “digital currency”, “cryptocurrency” and “virtual currency” plus sustainability in the Scopus, Web of Science and Google Scholar databases. “Digital Virtual Bitcoin + “Digital Cryptocurrency + Virtual Bitcoin Currency” + Cryptocurrency Currency + Sustain Currency” Sustain. Currency Sustain. Sustain. Scopus 819 5 553 1 217 4 254 1 Web of Science 502 4 377 0 124 2 147 1 Google scholar 24,800 1780 6480 1150 6490 563 14,500 2110 Table1 show that generally a small number of papers have been published considering the sustainability of bitcoin, digital currency, cryptocurrency or virtual currency. Furthermore, the literature Sustainability 2017, 9, 2214 3 of 11 SustainabilityTable2017 1 ,show9, 2214 that generally a small number of papers have been published considering3 of 11the sustainability of bitcoin, digital currency, cryptocurrency or virtual currency. Furthermore, the literature research showed that in all databases consulted the majority of papers have been research showed that in all databases consulted the majority of papers have been published in the last published in the last three years (2015, 2016 and 2017), probably because the bitcoin technology is three years (2015, 2016 and 2017), probably because the bitcoin technology is becoming more and more becoming more and more appreciated and globally used. appreciated and globally used. 3. Environmental Aspects of Sustainability 3. Environmental Aspects of Sustainability The environmental sustainability of bitcoins is a controversial question as the system has been The environmental sustainability of bitcoins is a controversial question as the system has been built in a way almost like the mining of a natural resource: costs and efforts rise as the system built in a way almost like the mining of a natural resource: costs and efforts rise as the system reaches the ultimate resource limit. In other words, just as the mining of copper or gold or crude oil reaches the ultimate resource limit. In other words, just as the mining of copper or gold or crude becomes more and more expensive and time consuming as we approach the finite quantitative limit, oil becomes more and more expensive and time consuming as we approach the finite quantitative so also the “mining” of new bitcoin requires more and more hardware resources necessary to limit, so also the “mining” of new bitcoin requires more and more hardware resources necessary to “mine” each bitcoin when approaching the capped limit of the bitcoin system. Bitcoin is based on the “mine” each bitcoin when approaching the capped limit of the bitcoin system. Bitcoin is based on the “blockchain technology” which relies on highly secure cryptographic algorithms and sophisticated “blockchain technology” which relies on highly secure cryptographic algorithms and sophisticated peer-to-peer technologies, which poses a challenge to both the usability and diffusion of bitcoins. peer-to-peer technologies, which poses a challenge to both the usability and diffusion of bitcoins.
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