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Buildings consume around 40% of total world energy and are responsible for 30-35% greenhouse gas emissions globally. Latent heat thermal energy storage is one of the most promising techniques being investigated currently to reduce the thermal load of buildings. Different types of phase change materials (PCMs) i.e. organic, inorganic and eutectics with different thermophysical properties have been investigated for passive cooling of buildings showing great potential for saving energy. Due to their higher thermal conductivity and high heat storage capacity per unit volume, inorganic phase change materials take advantage over organic ones. They can be used as stand-alone heat storage systems for free cooling, embedded in building walls, windows, roofs and ceilings etc. Studies have shown that there are some drawbacks of inorganic PCMs as well like corrosion of container material, phase separation and supercooling which require solutions.

In this document, we present a synthesis of updated documented experience in the implementation of mussel cultivation for mitigating effects of eutrophication and parameter estimates to facilitate potential application in coastal water management plans. Included are descriptions of potential for nutrient extraction, ecological effects, and economics of mussel cultivation. The documentation presented is primarily gathered in the BONUS OPTIMUS project as well as in some nationally funded projects on mussel farming or mussel mitigation farming including project participants, while data from other projects is only included to a lesser degree.

Spray drift is the movement of pesticide droplets through the air, during and after application, to unintended sites; drift can damage sensitive neighboring crops, hurt wildlife, and contaminate water supplies. This study hypothesized that it is possible to predict spray drift potential based on the knowledge of nozzle spray characteristics. The aim of the study was to quantify this relationship by: •collecting experimental data for nozzle spray characteristics (i.e., droplet size and -velocity distribution in the spray, spray fan width and flow rate through the nozzle at a given liquid pressure) for a broad variety of nozzles •measuring the potential spray drift in a wind tunnel •developing an empirical model based on experimental data for 10 hydraulic spray nozzles Droplet size and velocity were analyzed using laser-based equipment (Phase Doppler Anemometry), spray liquid distribution from a single nozzle was analyzed using a mechanical spray pattern analyzer, and spray drift potential was analyzed in a wind tunnel at wind speeds of 2, 4, and 6 m/s. The empirical model was developed based on the experimental data. The model predicted the spray drift potential of the studied nozzle types, and can be assumed to predict that of other nozzles or liquid pressures if the spray characteristics are known.

Formålet med RobustFish projektet var at: • Styrke udviklingen af økologisk ørredproduktion i Danmark men også til gavn for konventionelt opdræt • Undersøge ørredyngels robusthed i forhold til start-fodrings adfærd, fedtsyreindholdet i foderet og følsomhed over for yngeldødeligheds-syndromet (YDS) • Effekt af vandbehandling med hjælpestoffer • Viden om markedsforhold, forbrugerkendskab, produktudvikling og øget afsætning. Robustfish har adresseret ovennævnte problemstillinger, og på grundlag af opnåede resultater kan der drages følgende konklusioner og deraf følgende anbefalinger og perspektiver for styrkelse af det økologiske opdræt af regnbueørred i Danmark. • Yngel med tidlig fødesøgnings adfærd (swim-up) viste tendens til større robusthed over for de anvendte stress påvirkninger. • Der var ingen statistisk forskel mellem dødelighed forårsaget af YDS-bakterien Flavobacterium psychrophilum og ”Tidlig”, ”Mellem” og ”Sen” swim-up adfærd. • Udskiftning af marine protein kilder (kun 10 % fiskemel i diæterne) med vegetabilske viste negativ effekt på foderindtag, vækst og dødelighed i regnbueørred yngel. • Lavt indhold af flerumættede fedtsyrer (HUFA) i foderet (> 1 % af total fedtsyrer (TFA)) havde tilsyneladende kun lille påvirkning på vækst, foderkonvertering (FK) og enzymatisk aktivitet indtil 100 dage efter startfodring – i foder med optimal marin proteinkilde. • Fedtsyre resultater indikerede, at ørred tilsyneladende kan syntetisere kortere kædede fedtsyrer til HUFA. • De godkendte hjælpestoffer anvendes med større sikkerhed og dambrugerne er blevet fortrolige med produkterne, ligesom fiskene tilsyneladende tilpasser sig de grønne hjælpestoffer. • Behov for optimering af driften med henblik på dels at sikre en bedre og mere stabil vandkvalitet – og derved reducere brugen af hjælpestoffer og dels sikre fiskevelfærd, herunder også vandcirkulation, beluftning, overdækning, mm.). • Det vurderes at der vil være gode muligheder for at opretholde en merpris (20 – 30 %) på økologiske ørreder, og at markedsføring skal fokusere mere på dyrevelfærd end miljø. • Forbrugerne havde en negativ opfattelse af opdrættet fisk, der blev forbundet med noget negativt - på linje med industrialiseret landbrug og i modsætning til ”vile fisk”. • Kun få forbrugere var i stand til at identificere regler for økologisk fisk og ofte sammenblandedes de med MSC, ASC og andre certificeringer. • Der behov for en systematisk kommunikations-/forbrugeroplysningskampagne med fokus på større bevidsthed om ”Økologisk fisk”, der er opdrættet og kontrolleret i forhold til specifikke regler for økologisk akvakultur og at økomærket adskiller sig fra f. eks. miljømærkerne MSC og ASC. • Stigende efterspørgsel efter økologiske produkter i Europa vil være et godt afsætningsmæssigt grundlag for at fastholde målsætningen i regeringens 2020-plan for dansk akvakultur. Det anbefales at der skabes yderligere incitament til omlægning af dambrug til økologisk produktion.

The Organic Regulation of fish farming states strong limitations on the sourcing of protein and fat (oil) ingredients in organic feed, i.e. aiming to phase out fishmeal (FM) and fish oil (FO) obtained from wild fish stocks and this may lead to a higher inclusion of other ingredients, especially of vegetable origin including proteins i.e. soybean; wheat; corn; barley; cottonseed; canola and peas, and oils i.e.: soybean; canola; linseed; sunflower; palm oil a.o. (Gatlin et al., 2007). A complete substitution of (FM) by vegetable protein alternatives may, however, lead to reduced performance in salmonids. Nutritional deficiencies and lack of essential amino acids; high dietary levels of antinutrients/ carbohydrates are typical factors leading to lower feed intake; lower digestibility,- feed utilization and growth and may have additional consequences for survival and robustness. Several studies have shown that a total substitution of FO by individual or mixtures of vegetable oils do have same negatively effect on growth or feed efficiency provided that essential n-3 (Ω-3) and n-6 (Ω-6) long chain polyunsaturated fatty acids (LC-PUFA) requirements are met by the lipids contained in fish meal (Bell et al., 2003; Richard et al., 2006). Diets free of both FM and FO will contain no LC-PUFAs known to have specific important physiological functions. The three main important LC PUFAs are arachidonic acid (20:4 ARA Ω-6), eicosapentaenoic acid (20:5 EPA n-3) and docosahexaenoic acid (22:6 DHA n-3). While ARA is particularly important in reproduction, EPA and especially DHA are essential for neural development and as part of forming membranes and maintaining their fluidity (Sargent 1995). The addition of LC- PUFAs to vegetable based diets may improve performance and robustness of the fish and act as immune stimulants. Several studies were performed with rainbow trout fry with supplementation of LC-PUFAs (EPA+ DHA in diets for which FM and /or FO had been partly or fully substituted with alternative ingredients of primarily vegetable origin. Survival growth performance, enzymatic activity; immune response and analytical FA composition were used to evaluate effects.

The Organic Regulation of fish farming states strong limitations on the sourcing of protein and fat ingredients in organic feed, i.e. aiming to phase out fish oil (FO) obtained from wild fish stocks and this may lead to a higher inclusion of other oils, especially vegetable oils (VO) as these are widely used. Several studies have been carried out to investigate the possibility of using plant-based diets in rearing fish. Only very few of them have challenged start feeding fish with diets in which both fishmeal (FM) and FO have been substituted, while studies on larger grow out fish have shown that a combined replacement of FM and fish oil (FO) is feasible without detrimental effects in growth performance when the theoretical requirements for essential amino acids and fatty acids are met by the diet. Some recent studies have revealed, that it is possible to completely substitute FM and FO in feeds for rainbow trout over a 3 –year production cycle, but observed some limitations, such as reduction in feed-intake, offspring viability; smaller egg size and lower growth (Lazarotto et al., 2015). Other studies on rainbow trout with use of all plant based ingredients have caused a higher lipid deposition in the perivisceral fat. The lower growth performance could be a combination of lower feed intake and lower feed efficiency. This poorer growth effect of a totally plant-based diet is believed to be mainly related to the replacement of FM and not to the FO substitution as reported for several species investigated, rainbow trout; European seabass and gilthead sea bream. While it may not be recommended to fully substitute both the FM and FO with alternatives (vegetables) in diets for rainbow trout fry, a fully or partial replacement of either FM or FO could be possible. Relatively little information exists about how and if dietary FO replacement with vegetable oils and concomitantly change in FA composition may affect not only performance and survival, but also physiological markers such stress resilience and immunocompetence. Obvious changes in muscle fatty acid (FA) signatures and membranes (i.e. LC PUFAs) occur with the replacement of FO by vegetable oils (VO). The possible effects on fish health and welfare merits interest for research in this area. Indeed, adequate nutrition is essential to maintain health and to reduce disease susceptibility and pathological changes, and dietary lipids (as well as other nutritional factors) have specific actions on the immune response. In gilthead seabream (Sparus aurata) both the redox balance (Saera-Vila et al., 2009) and the cortisol response after stress confinement (Ganga et al.2011) were altered by a high replacement of FO by VOs. Even lower VO replacement levels (50-60%) increased the cumulative mortality in gilthead seabream challenged with Vibrio alginolyticus.

The EU regulation (EC 710/2009) on Organic Aquaculture states that the principles of organic rearing shall include the whole trout production cycle, i.e. the fish production shall be based on organic fry. The Organic Regulation of fish farming states strong limitations on the sourcing of protein and fat ingredients in organic feed, i.e. aiming to phase out fish oil obtained from wild fish stocks and this may lead to a higher inclusion of other oils, especially vegetable oils as these are widely used. The main difference between vegetable oils (VO) and fish oils (FO) is related to the content of so called long chain essential n-3 (previously denoted Ω-3) and n-6 (previously denoted Ω-6) polyunsaturated fatty acids (LC- PUFAs). These are main constituents of primarily marine oils (i.e. fish oil) but are non-existing in vegetable oils. LC– PUFAs are considered important in early fish larval and fry ontogenesis for optimal physiological development. The dietary content and requirement of specific essential n-3 and n-6 fatty acids is however generally regarded as less important in freshwater fishes than in marine fish species, as some freshwater fishes such as salmonids i.e. rainbow trout to a certain degree are capable to synthesize some of these essential fatty acids for their physiological requirements. Thus, substitution of marine oils with vegetable oils in feeds for organic aquaculture causes a reduced content of LC- PUFAs. Studies on salmonids (salmon, trout) have examined consequences for growth and physiological influences on juvenile and ongrowing salmonid fish, but little is known regarding short and long term effects on start feeding fry and their immunecompetance and ability to cope with stress and robustness towards inflectional diseases.