Climate change and carbon dioxide (

Climate change and carbon dioxide (CO2) based greenhouse gas (GHG) emissions have become a major challenge for the world. To address the challenge, many GHG emission standards have been published, and scientific measurement of GHG is the basis for the effective implementation of these standards. As an important component of GHG, carbon emission has become the key monitoring object of various organizations. Meanwhile, corporates are increasingly concerned about their sustainable development. They hope to quantify their contributions to global climate change and take measures to control their carbon emissions through some carbon footprint projects [1].Against this background, the concept of corporate carbon footprint (CCF) is proposed to measure corporate carbon emissions. Different from measuring carbon emissions by ‘land area’ (m2, km2, etc.), CCF refers to the total amount of carbon emissions caused by activities of a corporate, derived from the ecological footprint [2]. It does not require various assumptions, thus avoiding the increase in uncertainty. Based on CCF estimation, carbon auditing and carbon accounting can be conducted to measure the environmental performance of a corporate [2].A lot of protocols and standards have been published to provide guidances on how to calculate carbon emissions, such as ISO 14067 [3], PAS 2050 [4], WBCSD/WRI 2004 [5]. Among them, WBCSD/WRI is the most widely used standard, which divides the carbon emission into three categories: direct emission, indirect emission caused by electricity, heat or cooling used, and indirect emission in upstream and downstream of the value chain. Currently, there is no a generally accepted method for carbon emission estimation [6]. The following three methods are mainly used to measure CCF in life-long cycle analysis (LCA) in existing studies: the bottom-up method based on process analysis (PA), top-down method based on environmental input-output (EIO) analysis, and a hybrid EIO-LCA method to combine the advantages of the aforementioned two methods [7].The existing standards and methods have many limitations and shortcomings. Firstly, most of the current corporate carbon emission estimation methods are specially designed，for a company or a type of companies based on LCA. They are not universal and cannot be directly applied to another different corporate or industry. For example, the CCF calculation is proposed for a wine production company in [8], for the cement industry in [9], for the manufacturing industry in [10], respectively. Secondly, there are few studies on device-level carbon emissions, and most of them are mainly for household devices rather than industrial devices [8]–[10]. Thirdly, the existing methods are for pre-evaluation or post-evaluation, not for real-time. Real-time carbon monitoring can help cope with the changing environment by providing information and give some suggestions to control the emission.Aimed at addressing these deficiencies, a universal real-time corporate carbon footprint measurement framework is proposed in this paper. This work focuses on the mandatory requirements set by the WBCSD/WRI protocol: the direct emission (scope 1) and indirect emission caused by the use of electricity (scope 2). For scope 1, a CNN-BLSTM based load identification method is proposed to monitor the states of devices in real-time, and then calculate the direct emission in combination with the device carbon emission intensities; for scope 2, a more accurate estimation method of carbon emissions in a given period based on the marginal carbon emission factor is used. The proposed framework can provide more general and accurate CCF measurements, which can not only measure the overall emissions of the entire corporate but also provide more refined device-level carbon emissions.II. CNN-BLSTM BASED CORPORATE CARBON EMISSION ESTIMATION FRAMEWORK