This report contains a basis to follow the development of energy use continuously for digital infrastructure and digital systems, in particular data centers, as well as its impact on the energy system. The use of electricity in data centers has recently received attention by the general public, media and policy/law makers. Data centers are fundamental infrastructures for the society like roads. Data centers are central in the digitalization and for the ongoing green transformation of the industry. The energy use in data centers is around 1−2% of the global electricity use and far below the dramatic numbers shown in media. The report covers data center infrastructures. A data center is the facility that hosts the computers we use when we access the web, use applications or when industries process data in the background. Most of the energy in an efficient data center goes to the IT servers. Data centers can be classified into categories and are of different sizes. Data centers in office buildings for the company internal use is usually smaller less than 300 kW and the cloud company facilities are large at above 10 MW. Crypto mining facilities are not included in this report. To assess the energy use, a few methods are available. In the short-time frame of this study, RISE relies on already available reports, interviews and some statistics received. In the long run a governmental policy-based requirement on reporting from the data center operators will ensure transparency and quality of the assessment. The development of the data center market in Sweden still follows what is outlined in a recent Swedish report by Radar (Wallin, Werner, & Olofsson, 2020). The last years Sweden has seen an increased activity by large cloud companies in Sweden. It has resulted in a higher growth rate of the energy use compared to European or global numbers. RISE assesses that the current energy use by data centers in Sweden to be 2,8−3,2 TWh during the year 2022 using calculations based on the Radar report. Looking into the future is more difficult. Since more larger data centers still are under construction and will be built in Sweden and workloads from Europe will continue moving to Sweden and so it is reasonable that the trend for the growth of energy use will stay above EU average until year 2025. Due to the new tax regulations and current economic downturn, it will though be at a slower pace than between 2018−2022. RISE estimates half the growth rate of the Radar report due to this. RISE assesses and calculates the estimated energy use by data centers in Sweden will be 4,0−4,4 TWh per year by 2025. Beyond 2025 there are many uncertainties. A cautious estimate is 4,4−5,2 TWh per year for year 2030. Data centers can play an important role in the integration with the energy systems. For example, can data centers perform peak-shaving and energy arbitrage as well as act on the frequency ancillary markets. Also, the excess heat from data centers can be used in industrial symbiosis with heating applications such as district heating networks or greenhouses. Another important aspect is that it is more to environmental impact of data centers than energy efficiency. Analysis of the life cycle of all equipment and the operations needs to be done as well as monitoring other metrics than energy use for example water usage. Many new technologies are and will be developed to improve the energy efficiency and operations of data centers. Higher density of compute per square meter will require new cooling methods like liquid cooling, edge computing will require small compute nodes inside the networks and on-site production of electricity with fuel cells is another new development. Swedish industry is a leader in sustainable data centers. Many new innovations and products are coming from a growing industry sector. Recently a Swedish data center industry association has been formed. The European commission is active to develop visions and strategies for the future of Europe. A policy program “Path to the digital decade” will ensure an increased use of digital services and hence data centers supported by the Green deal initiative. There are three new initiatives on energy efficiency, the Energy Efficiency Directive (EED) updated with data centers, the Corporate Sustainability Reporting Directive (CSRD) and The EU Taxonomy for environmentally sustainable economic activities, that are also impacting the data center industry with increased transparency of metrics from the data centers. A supportive activity is the EU Code of conduct that can help data center operators to assess and improve their operations. Also, other initiatives are ongoing like the Climate neutral data center pact, the IMasons Climate Accord and the Sustainable Digital Infrastructure Alliance.