## 1 Introduction  
Government agencies around the world are increasingly advancing social and environmental policy goals by leveraging their own procurement dollars. Their influence on the market can be substantial, given the overall size and volume of purchasing that moves through government procurement offices. \"The average share of public procurement in gross domestic product (GDP) in OECD countries is about 11%, reaching 16% in the countries of the European Union\" [1] (p. 41). Government expenditure on works, goods and services represents around 14% of EU GDP, accounting for roughly EUR 1.8 trillion annually [2]. \"The EU's Europe 2020 Strategy (Europe 2020) and Renewed Sustainable Development Strategy (Renewed SDS) identify green public procurement (GPP) as an essential market-based instrument for attaining the EU's economic and environmental objectives\" [3] (p. 174). Green public procurement (GPP) is a policy instrument designed to utilize this vast spending power to increase environmental protection and advance more environmentally sustainable economies. The European Commission defines GPP as: \"a process whereby public authorities seek to procure goods, services and works with a reduced environmental impact throughout their life cycle when compared to goods, services and works with the same primary function that would otherwise be procured\" [2] (p. 4). Sustainable Public Procurement (SPP) is a similar concept referring to \"a process by which public authorities seek to achieve the appropriate balance between the three pillars of sustainable development--economic, social and environmental--when procuring goods, services or works at all stages of the project\" [4]. SPP aims to improve environmental protection, energy saving, as well as labor security, small and medium-size enterprises support and a regional balance [5]. In light of this, GPP is subsumed within SPP with a focus on an environmental dimension. In this research, green award criteria are used to identify green contracts. From a broad perspective, green criteria involve various environmental aspects and procurement procedures. In practice, GPP criteria can be environmentally related requirements set up by procurers during every step of the procurement process. GPP criterion is not only standard for identifying green products, but also for recognizing green suppliers and services. From the perspective of Life Cycle Costing, a GPP criterion not only involves the environmental impact of terminal products but also the impact of a raw material, production process, supply chain, and disposal phrases. We investigate the award criteria in the contract award notice and in the stage of awarding or choosing the winner of the bids using life cycle analysis. The peer reviewed research on factors affecting the uptake of GPP from empirical economic standpoint is rather limited, although it is of apparent significance given the scale of carbon, water, and material footprints that government can cut through environmentally responsible procurement [6]. [PERSON], [PERSON], [PERSON], and [PERSON] [7] estimated how green criteria such as environmental management systems (EMS), eco labeling, and chemical restrictions affect a supplier's decision on whether to participate in procurement bids. They used the procurement data of the cleaning service sector from Sweden and got the result that GPP \"was not effective as an environmental policy instrument\" [7] (p. 506). However, EMS in their analysis was negatively affected by the participation possibility, which might indicate the costly implementation of the relevant systems. [PERSON], [PERSON], [PERSON], and [PERSON] [8] focused on public sectors' GPP adoption by interviewing 156 public authorities in Italy to answer the question of whether the awareness of a GPP toolkit and regulations, external assistance, the dimension of public authority, and ISO 14001 certification can influence the uptake of GPP practices.