# Sustainability Audit of University Websites in Poland:
## 2 Background  
When applied to websites, low-emission and sustainable development principles concern hosting, information and interface architecture, and digital asset management set to minimise their adverse environmental impact. There are many standards, good practices, and design recommendations that provide practical schemes of action based on areas such as W3C specifications (including WCAG), SEO (particularly Technical SEO), green software engineering, sustainable interaction design (SID), and eco-friendly UX. A website's emissions performance is driven mainly by the size of data transfer and the asset loading (rendering) time it causes. According to the findings presented by [PERSON] and [PERSON] [18], transfers of large amounts of data lead to significant energy consumption in data centres, transfer networks, and terminals. A website's indirect carbon footprint can be effectively reduced by limiting the amount of data involved in a browser page lifecycle through image compression, code unification, and exclusion of excessive libraries. In light of the above, the Green Web Foundation [19] proposes eight principles for designing low-emission digital solutions (green software engineering, GSE, framework). Some of them apply to websites: (1) ensure energy efficiency through website design that reducesenergy consumption on the server and user sides; (2) maintain networking efficiency: minimise data transfers through compression, caching, and reducing the number of HTTP requests; (3) practice carbon awareness, i.e., shifting computational loads to places and times when renewable energy is available; and (4) use green hosting powered by renewable energy. This approach combines software engineering, sustainable development, and ecology, contributing to climate change prevention efforts in the digital domain [4]. In his sustainable interaction design framework, [PERSON] [20] demonstrated the need for designing digital interactions so that they both serve the user and help reduce environmental pressure. Sustainable interaction design involves designing human-technology interactions with consideration for the long-term impact of digital products on the natural environment. It emphasises interface simplicity, limiting the number of components that require significant computing capabilities (such as videos, animations, and interactive widgets), and reasonable content arrangement to facilitate navigation and reduce unnecessary interactions. Web accessibility is an essential aspect of website and mobile application design. Although it primarily concerns inclusivity, conformity with the Web Content Accessibility Guidelines (WCAG) often yields improved code structure (in both HTML and CSS), shorter rendering times, and reduced resource usage, all of which contribute to sustainable design [21]. Considering all these factors, sustainable website design appears to concentrate on four critical areas. The first one is data transfer optimisation. It involves reducing the size of files and curtailing HTTP requests to reduce energy consumption in the network infrastructure. The second domain is energy consumption optimisation through website design aimed at quick loading and limited use of user computational power. The third pillar is hosting and terminals powered with renewable energy to reduce the website's overall carbon footprint. The final concern is sustainable user interface design, which involves creating user-friendly graphical interfaces that require minimal processing power while ensuring a positive user experience (UX). Together, these components form a coherent strategy to minimise the environmental impact of websites and web applications. Note that these principles are consistent with the Sustainable Development Goals (SDGs), namely SDG 12, Responsible Consumption and Production, and SDG 13, Climate Action. The literature and practitioners often combine these approaches with SEO audits and tools, such as Ecograde, Website Carbon Calculator, and Digital Beacon, which empirically estimate a website's environmental impact.