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Pressure is mounting in the construction industry to adopt more environmentally sustainable methods to reduce CO2 emissions. Portland cement (PC) often constitutes to more than two-thirds of the embodied energy of concrete, and its production generates 5% of global greenhouse gas emissions. One efficient strategy to reduce the cement content without sacrificing performance is the use of particle packing models (PPM) to mix- proportion concrete mixtures with low cement content, the so-called low cement content (LCC) concrete. If on the one hand LCC was seen to be an effective sustainable alternative to the construction industry, its mechanical behaviour, durability and long-term performance are still under debate and thus further research is needed in the area. In this project, continuous PPM theories were used to mix- design structural concrete mixes presenting distinct mechanical properties (i.e. 25 & 35 MPa) and cement contents. Their performance was evaluated in the fresh and hardened states, and gaps, recommendations, and further needs were highlighted. Results show that the use of PPM enables the development of LCC systems, showing impressive hardened state performance (i.e. higher compressive strength and modulus of elasticity and lower electrical resistivity) and low carbon footprint. However, challenges in the fresh state were faced, which may be potentially solved with the use of chemical admixtures, fillers and/or supplementary cementing materials (SCMs).

Stadsdelen Sätra som ligger 3 km norr om Gävle centrum uppfördes undermiljonprogrammet mellan 1960-1974. Det är enkelt och ta sig till och från Sätramed både fordon, cykel och till fots. AB Gavlegårdarna har tagit initiativ till attrenovera deras byggnadsbestånd som uppfördes under miljonprogrammet istadsdelen Sätra, däribland Sicksackvägen 39. Byggnaden har byggts 1969 ifunktionalistisk stil i närheten av Sätra Centrum.Syftet med denna studie var att undersöka den kostnadsoptimala isoleringstjocklenvid invändig eller utvändig tilläggsisolering av husets ytterväggar. Med hänsyn tillandra åtgärder som AB Gavlegårdarna vill genomföra vid renovering av denbefintliga byggnaden.För att genomföra denna studie har en okulärbesiktning, litteraturstudie,beräkningar, uppmätningar, undersökningar, samt energisimulering utförts. Därpåjämfördes lönsamheten vid tilläggsisolering med optimala isoleringstjocklekeninvändigt respektive utvändigt.Resultatet av denna studie visar att de komponenter i husets klimatskärm somläcker mest värme är ytterväggar och fönster. Med hänsyn taget till derenoveringsåtgärder som AB Gavlegårdarna ska genomföra blir den optimalaisoleringstjockleken invändigt är 45 mm och utvändigt 170 mm. Den åtgärd som germest lönsamhet är tilläggsisolering utvändigt med 170 mm mineralull i kombinationmed AB Gavlegårdarnas renoveringsåtgärder: fönsterbyte och uppgradering avventilationssystemet till FTX.

The food industry has an essential role in society and in the global economy. Nowadays, modernlifestyle demands convenience, which is driving the development of the food sector. This isparticularly evident with convenience food, especially ready-made meals, industrially preparedfood, which only requires a short preparation time at home by consumers, but has very complexand diverse supply chains and is associated with a range of sustainability issues. Therefore, theaim of this research is to evaluate the environmental, economic and social sustainability in theready-made meals sector with the focus on the UK market. A life cycle approach has been used forthese purposes, using life cycle assessment (LCA) as the tool for the environmental analysis, lifecycle costing (LCC) for the economic aspects and social sustainability indicators (SI) for the socialissues. Different types of ready-made meal from different cuisines have been considered, includingthe British, Italian, Chinese and Indian. The highest environmental impacts are found for the Italian and Indian cuisines, while Chinesemeals are environmentally most sustainable, followed by the British. At the sectoral level, theresults suggest that from ‘cradle to retailer’ the British ready-made meal sector contributes 4.45 Mtof CO2 eq. annually, which represents ~4% of the GHG emissions of the food and drink sector and~1% of the UK GHG emissions. Of this, 3.16 Mt of CO2 eq. is emitted by chilled and 1.28 Mt of CO2eq. by the frozen ready-made meals. The total life cycle costs at the sectoral level from ‘cradle tograve’ are estimated at £2.1 bn, with the chilled ready-made meals market contributing £1.42 bnand the frozen £676 million. The life cycle costs from ‘cradle to retailer’ are £1.02 bn, with the valueadded of £958 million. The common environmental and cost hotspot for all the meals studied is rawmaterials. In particular, the meat, fish and seafood are the greatest contributors. For theenvironmental impacts, the manufacturing and distribution stages are also important, while theconsumption stage is the largest contributor to the costs. The major social aspects are the foodrelated health issues and food security, in particular food affordability. In the supply chainagriculture, wholesale and retailers show high risk for indicators such as wages and employmentwhile the manufacturing presents high risk in fatal injuries. The study also shows that consumer choices play an important role for the economic andenvironmental impacts; therefore, educational programmes and better communicational strategiesshould be implemented by the industry, the government and consumers groups. Moreover, toensure a sustainable development of the ready-made meals sector, future policies and industrialinitiatives should consider a life cycle approach including relevant economic, environmental andsocial aspects.

In an attempt to meet its ambitious climate change targets, the UK government has decided to incentivise the uptake of bioenergy. However, the full economic costs and environmental impacts of this decision have not yet been quantified at a national level. This is the topic of this research which evaluates the life cycle environmental and economic sustainability of different options for electricity and heat generation using biomass available in the UK, notably waste wood, agricultural residues and wastes, straw, municipal solid waste (MSW), food waste, and energy crops. These results are then used to evaluate the environmental impacts and costs for the whole bioenergy sector in the UK.The results suggest that the environmentally and economically most sustainable electricity generating options are, in descending order: manure/agricultural residue anaerobic digestion (AD) combined heat and power (CHP), Miscanthus co-firing with coal, and chicken litter gasification CHP. The most sustainable heat-generating systems are manure/agricultural residue ADC CHP, waste wood gasification CHP, and chicken litter gasification CHP. However, the use of these technologies is limited by the availability of their respective feedstocks. The research finds that there is currently 30.4 million odt of biomass produced annually in the UK which could be used for electricity and heat generation and that potentially 77.8 million odt could be produced if greater amounts of energy crops are grown. Dry biomass makes up the largest proportion of available biomass, which itself largely consists of wood wastes and energy crops. Dry biomass can therefore make the largest contribution of electricity or heat to potential bioenergy sectors. The electricity-generating biotechnologies identified as those which would make the most sustainable use of wood wastes and energy crops are biomass power plants and co-firing plants. Heat would be most sustainably generated from these feedstocks using biomass gasification CHPs and biomass boilers. According to the results, it is more sustainable to use the UK’s current and potential biomass resources for generating electricity, rather than for producing heat. Electricity from biomass has higher potential for reducing the majority of environmental impacts compared to the current UK electricity grid. Despite this, some impacts are expected to increase, including eutrophication, terrestrial ecotoxicity, depletion of elements and acidification. Furthermore, the economic sustainability of most biomass options is often dependent on subsidies being available, mainly because of the high capital costs. It is recommended that the government look beyond climate change and consider full life cycle impacts when deciding which technologies to incentivise to avoid solving the one problem at the expense of others. It is also advised that subsidies be tied to the sustainability of the feedstock, incentivising the use of waste over energy crops (at least in the short term) and encouraging the displacement of coal and oil. Furthermore, the government should consider scaling the FIT and RHI subsidies smoothly with capacity and consider scaling ROC payments which are currently not linked to capacity at all. Improvements to the environmental sustainability of bioenergy could be gained by funding research into cleaning emissions from biomass combustion, enforcing strict regulation of ash disposal and digestate treatment, and encouraging the reuse and recycling of rare elements.

Bostads- och servicesektorn står för ungefär 40 % av Sveriges. Total energianvändning. En stor andel går till att värma byggnader. Idag är det dominerande uppvärmningssystemet fjärrvärmen i flerbostadshus i Sverige. Från och med den 31 december 2020 ska alla nya byggnader i EU vara nära nollenergibyggnader.Därför ställs hårdare energikrav påbyggnaderna och uppsatsens författare ställer sig frågan om fjärrvärmen verkligen kommer att vara det mest lämpliga Uppvärmningssystemet i framtidens nya stadsdelar med låg energianvändning.

The residential construction sector in the UK plays an important role in society’s wellbeing as it provides shelter, employment and promotes economic growth. However, the sector has been identified as a large contributor to climate change, resource depletion and is associated with different socio-economic issues such as fuel poverty and house affordability. The residential construction sector is growing quickly due to a high housing demand, as will the associated impacts unless significant changes are made. Several studies have assessed the environmental impacts of the residential construction sector, while the social and economic aspects of sustainability are often ignored but are equally important for sustainable development. This thesis presents a sustainability assessment framework capable of addressing the environmental, economic and social issues of the residential construction sector supply chain, using a life cycle approach in order to contribute toward an improved understanding of the current and future trends in the sector.The methodology developed has been applied to the residential construction sector in the UK and demonstrated through three case studies of conventional, passive and zero-carbon houses as well as a sustainability assessment at the sectoral level. The main stakeholders identified here are construction companies and workforce, home owners and occupiers, suppliers, local authorities and the government. The main sustainability issues are resource depletion, waste generation, environmental impacts such as global warming (GWP), ozone depletion, house price and affordability, contribution to GDP, provision of employment, health and safety, impact on local communities and business ethics. The assessment tools used to assess the environmental and economic sustainability are Life Cycle Assessment (LCA) and Life Cycle Costing (LCC), respectively. Social sustainability has been assessed using different social sustainability indicators applicable to the residential construction sector. LCA results indicate that zero-carbon houses have the lowest GWP of the three house types considered, being 71% lower than for the conventional house, compared to a 59% reduction for passive houses. However, passive houses have a better overall environmental performance as they have the lowest impacts for most environmental impact categories. LCC results, on the other hand, indicate that the total life cycle costs for zero-carbon houses are 21% higher than for conventional houses because of the additional cost of renewable technologies, while for passive houses costs are comparable to conventional houses. At a sectoral level, zero-carbon houses can achieve reductions of 13% of the sector’s annual GWP compared to conventional houses, however this will cost the residential construction sector an additional £3 billion per year. The construction of passive houses will cost an additional £1 billion per year compared to conventional houses but can help by reducing the sector’s annual GWP by 10%.This study shows that the current state of the housing sector is environmentally unsustainable and urgent changes must be made in the way houses are constructed and managed. However, the residential construction sector must overcome many socio-economic barriers before introducing low-carbon houses on a large scale.

We have been traveling on roads for hundreds of years and the development during those years has led to safer roads. Barriers between the two traffic lanes have been one of the most important measures to prevent cross-median collisions. In 1998, the world's first cable barrier was arranged and ever since, there have been discussions held about the cable barrier’s function and maintenance cost. This report shows, like many before, that the cable barrier is more expensive in maintenance costs from a life cycle perspective than the steel beam is. The 2+1 road's working environment is considered to be a problem for operating contractors, rescue personnel and others who may be working on the road. The road itself is quite narrow and the surrounding traffic passes close by the workers. This could be avoided with an extra traffic lane, like a 2+2 road. The costs to society, caused by traffic delays and fatal and severe injuries, would probably also decrease, while statistics proves less accidents due to driving into the midbarrier on a 2+2 road, than a 2+1 road. Similarly to this, statistics also indicates that the 2+2 road would provide a smoother traffic flow and a higher traffic safety. LCC is an abbreviation for Life-Cycle Cost and is a method for calculating and comparing different investment options. The two main alternatives calculated are the 2+1 road with cable barrier and the 2+2 road with steel beam. A third alternative, 2+1 road with steel beam has also been compared in this report. The results show the 2+2 road’s top layers with steel beam barrier included, is less expensive over years, than the 2+1 road’s top layers with cable barrier or with steel beam barrier. The maintenance costs have been calculated over a period of 30, 40 and 60 years, in order to analyze the cost variations over different periods. The initial cost of the 2+2-road is of little importance in relation to the probable increased road safety, the safer work environment and hopefully the lower society costs. Especially when the 2+2 road is less costly after already 20 years. / Vi har färdats på vägar i hundratals år och utvecklingen har lett till jämnare och säkrare vägar. En del i detta arbete har varit mittseparationer för att förhindra mötesolyckor. År 1998 sattes världens första stållineräcke upp och ända sen dess har diskussioner förts om dess funktion och underhållskostnad. Denna rapport visar att vajern på en 2+1-väg är dyrare i underhållskostnader ur ett livscykelperspektiv, än vad stålbalken är på en 2+2-väg.  2+1-vägens arbetsmiljö anses vara ett problem för driftentreprenörer, räddningspersonal och andra som kan komma att arbeta på eller vid vägen. Detta beror på att vägen är smal och att omgivande trafik passerar väldigt nära de arbetande. Detta skulle undvikas med en extra körfil, som vid en 2+2-väg. Där skulle troligtvis även samhällskostnaderna minska, då statistik visar att räckespåkörningar är färre vid en 2+2-väg i relation till en 2+1-väg. Likaså finns statistik som tyder på att 2+2-vägen skulle ge ett jämnare trafikflöde och därmed högre trafiksäkerhet.  LCC är en förkortning för Life-Cycle Cost och är en metod för att beräkna och jämföra olika investeringsalternativ. De två huvudalternativ som beräknats är 2+1-vägen med stållineräcke och 2+2-vägen med stålbalk. Även ett tredje alternativ, 2+1-väg med stålbalk har jämförts i denna rapport.  Resultaten visar att 2+2-vägens överbyggnad med stålbalk och mittremsa, är dyrare att bygga, men mindre kostsam i underhåll över kalkylperioderna 30, 40 och 60 år, gentemot 2+1-vägens överbyggnad med vajer, respektive stålbalk.   De initiala kostnaderna väger lätt i relation till trolig förhöjd trafiksäkerhet, tryggare arbetsmiljö och förhoppningsvis lägre samhällskostnader, med tanke på att 2+2-vägen är mindre kostsam efter redan 20 år.

Denna rapport undersöker två olika ventilationsalternativ ur en livscykelanalys. De två ventilationssystemen är konstantflödessystem kontra närvarostyrd ventilationslösning. Syftet med rapporten var att undersöka kostnaderna och energianvändningen för respektive system, sett till hela livslängden med hjälp av Energimyndighetens livscykelkostnadsverktyg (LCC-verktyg). Rapporten resulterade i att närvarostyrd ventilation inte är lönsamt med dagens energipriser och att investeringskostnaden inte återbetalar sig om det endast räknas på ventilationen. Däremot halveras energiförbrukningen för det närvarostyrda systemet. Slutsatsen av rapporten är att om investeringar skall vara lönsamma inom närvarostyrda system bör kyla, värme, belysning och ventilation arbeta tillsammans efter närvaro.

En energieffektiv geoenergianläggning kan åstadkommas genom att välja rätt systemtemperatur. Systemtemperaturerna påverkas av geoenergisystemets delkomponenter. Syftet har varit att genomföra en teknoekonomisk utvärdering av värmesystemets systemtemperatur i geoenergiprojekt. Arbetet påbörjades med en teknisk utvärdering av systemtemperaturen för att undersöka vilka parametrar som har en betydande inverkan på systemtemperaturen. Därefter genomfördes en ekonomisk utvärdering på systemtemperaturen. Den ekonomiska utvärderingen utfördes genom att utvärdera olika systemtemperaturers livscykelkostnad (LCC) i en referensbyggnad. Resultatet visade tydligt att LCC ökar med sänkt framledningstemperatur. Vid systemtemperaturer över grundfallets systemtemperatur som har framledning-/returtemperatur på 40/30 °C, sjönk LCC med 1–2% per grad och vid framledning-/returtemperaturer under 40/30 °C ökade LCC med 6–8% per grad. De faktorer som hade störst inverkan på systemtemperaturen var byggnadens värmebehov, byggnadens utformning och slutapparaternas effektivitet. Dessa faktorer avgör hur låg systemtemperatur som är möjligt att implementera i en byggnad.