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Underground cabling has become a true alternative in construction of electricity distribution networks, even in rural areas. The increasing amount of underground installations requires strategic work that helps to define the most profitable cabling targets. The purpose of this paper is to introduce a methodology to consider the underground cabling process.

The paper proposes a cabling concept that covers the issues on how cabling should be carried out. The analysis is based on techno‐economic and reliability analyses. The methodology consists of several steps that together constitute the concept.

The underground cabling concept comprises several steps that can be simplified into questions: where, what, when and how the network cabling process is carried out. The analysis of these questions and the related features of the network show that different approaches to the renovation can cause significant differences in profitability between the renovation strategies.

The underground cabling concept provides a method to analyse the cabling process, and it contains several alternatives for applying the concept. Thus, the applicability of a certain method depends on the network and the objectives of the distribution system operator.

Renovation planning of the network has become common in distribution companies. Traditionally, ageing of the network has been the driver for the renovation. However, in the future, the scope of renovation planning should also include other renovation drivers, such as reliability.

The methodology proposed in the paper can be applied in the renovation and development process of distribution networks. The results are universal in the electricity distribution.

The purpose of this paper is to establish a methodological framework to address key issues in electricity distribution network development. The paper defines subtasks in the strategy process and presents key elements in the strategy work and long‐term network planning. The results are illustrated by a case network.

The paper describes the methodology for cost and reliability analyses in the strategy work. The focus is on techno‐economic feasibility of certain network development technologies in the network strategy and the surveys are linked to economic regulation, specifically to reliability of supply and allowed return. The study addresses the stages of strategic decision making and compilation of investment strategies.

The strategic planning concept and methods are applicable in practice; the results have proven valuable in the long‐term business development and in discussions with the company owners. Outage costs are an essential element in the economic regulation of the business, reliability being a key driver in network planning.

There is no universal solution to strategic decision making, but each development task is highly case specific. This is due to diverging operating environments and targets set by the company owners; these issues strongly influence the strategy process.

The work illustrates strategic planning in an actual distribution company and shows how the methodology can be applied to the strategic network development. Nevertheless, the results cannot be generalised as such, but each network has to be considered individually.

The proposed concept can be applied to the long‐term development of distribution networks. The results are internationally applicable, yet diverging regulatory models call for specific methodology in each country.

While aiming to create methods for fibre recycling, the question of colours in waste textiles is also in focus; whether the colour should be kept or should be removed while recycling textile fibre. More knowledge is needed for colour management in a circular economy approach.

The research included the use of different dye types in a cotton dyeing process, the process for decolourizing and the results. Two reactive dyes, two direct dyes and one vat dye were used in the study. Four chemical treatment sequences were used to evaluate colour removal from the dyed cotton fabrics, namely, HCE-A, HCE-P-A, HCE-Z-P-A and HCE-Y-A.

The objective was to evaluate how different chemical refining sequences remove colour from direct, reactive and vat dyed cotton fabrics, and how they influence the specific cellulose properties. Dyeing methods and the used refining sequences influence the degree of colour removal. The highest achieved final brightness of refined cotton materials were between 71 and 91 per cent ISO brightness, depending on the dyeing method used.

Only cotton fibre and three different colour types were tested.

With cotton waste, it appears to be easier to remove the colour than to retain it, especially if the textile contains polyester residues, which are desired to be removed in the textile refining stage.

Colour management in the CE context is an important new track to study in the context of the increasing amount of textile waste used as a raw material.