This comparative life-cycle assessment highlights three main alternatives for renovation of waste water sewerage: pipe replacement, cured- in- place pipe (CIPP) lining (also called sliplining) and renovation by coatings. The functional unit of this study is a six-story block house that was built in 1960 and has 29 apartments. The characterized results of environmental impacts display an advantage for CIPP-lining over pipe replacement in 14 of the 18 studied impact categories. Regarding those categories in which impacts were comparatively large, when looking at the average impact from a European citizen according to the ReCiPe methodology for life cycle inventory list, pipe replacement has greater impacts than CIPP-lining. In general, the impacts of pipe replacement are related to new tiles, expanded polyester cement, the screed, and the material for waterproofing, as well as the electricity needed for drying the structure. The CIPP-lining method displays higher impacts than pipe replacement in just four categories. These impacts are, to a large extent, caused by the use of consumables such as gloves and cotton cloths. From an LCA-perspective, the study shows that the CIPP and coatings relining methods have advantages over pipe replacement under the condition that the technical lifetime is the same for these methods. Still, the uncertainty of service life, as well as Bisphenol A (BPA) emissions, remain as issues of concern for further study. There are also other differences among the alternatives that ultimately influence a property owner's choice of method, such as costs, inconvenience for the residents, renewal of bathroom interiors, and the way in which the property owner values the alternative technologies.

Principles based on the quality of energy, namely exergy, can assist in attaining a more efficient and cleaner energy supply structure. This paper analyzes two building clusters in campus areas based on a stepwise approach with four steps according to the Rational Exergy Management Model. The clusters involve 8 buildings at the KTH Royal Institute of Technology and those in the Albano district that is a former industrial site and will become a joint campus area in Stockholm. The energy supply for the campus and urban vicinity includes a combined heat and power plant with district heating and cooling. In this context, the energy and exergy profiles of the building clusters are compared. The level of exergy match in the energy system is analyzed. Four scenarios are then devised, which involve energy savings and different shares of various supply options. These include a new biofuel unit, seawater heat pumps, large scale aquifer thermal energy storage, heat supply from solar collectors, and electricity and heat from photovoltaic thermal arrays. The present case and four scenarios are found to have exergy matches that range between 0.49 and 0.81. The scenarios indicate that savings of 16 GWh energy, 9.6 GWh exergy, and 2663 tonnes of carbon dioxide emissions are possible. The paper contributes to exergy based analyzes for campus areas and concludes with the prospect of using campus areas as pioneering case studies for advancing the transition to cleaner energy scenarios.

This report is designed to be a comprehensive information resource for Swedish prosumers considering an investment in solar PV systems. The target audience are multi-family cooperative houses, however much of the information is applicable to other building owners and solar energy more broadly. The primary question to be answered; is a rooftop PV investment profitable in Sweden? Naturally there are many variables that can affect the answer; therefore a Monte Carlo methodology is used to convert the uncertainties into risks, where the results can be presented as probabilities rather than a vast collection of sensitivity analyses. Several policy scenarios are tested, where the relative impact of each current program on profitability can be seen.

The comparison of building clusters based on energy and the quality of energy (exergy) is a

key aspect for determining steps towards cleaner energy supply structures. This paper

compares two building clusters based on an integrated approach that involves building and

energy system level analyses. The first cluster involves 8 buildings with diverse energy profiles

at the KTH Royal Institute of Technology campus, including faculty buildings, laboratories, and

a data center with waste heat recovery. The second cluster involves planned buildings in the

Albano district in the vicinity of the KTH campus that will be a joint area with lecture buildings

and accommodation for 3 universities in Stockholm. The present energy supply structure for

the campus and the surrounding urban area includes a local combined heat and power (CHP)

plant. The comparison of the building clusters involve analyses based on the Rational Exergy

Management Model. Four scenarios, which involve different shares for the existing CHP units,

new biofuel CHP unit, seawater heat pumps, peak load boilers, electric boilers, large scale

aquifer thermal energy storage, heat supply from solar collectors, and electricity and heat from

photovoltaic thermal arrays are devised for comparison. The scenarios have at most an exergy

match of 0.81. The paper concludes with useful results that are in line with the aims of IEA

Annex 64 on Optimised Performance of Energy Supply Systems with Exergy Principles.