In order to gain a more mature share in the future energy supply, green gas supply chains face some interesting challenges. In this thesis green gas supply chains, based on codigestion of cow manure and maize, are considered. The produced biogas is upgraded to natural gas quality and injected into the existing distribution gas grid and thus replacing natural gas. Literature research showed that relatively much attention has been paid up to now to elements of such supply chains. Research into digestion technology, agricultural aspects of (energy) crops and logistics of biomass are examples of this. This knowledge is indispensable, but how this knowledge should be combined to help understand how future green gas systems may look like, remains a white spot in the current knowledge. This thesis is an effort to fill this gap. A practical but sound way of modeling green gassupply chains was developed, taking costs and sustainability criteria into account. The way such supply chains can deal with season dependent gas demand was also investigated. This research was further expanded into a geographical model to simulate several degrees of natural gas replacement by green gas. Finally, ways to optimize green gas supply chains in terms of energy efficiency and greenhouse gas reduction were explored.
In Europe, green hydrogen and biogas/green gas are considered important renewable energy carriers, besides renewable electricity and heat. Still, incentives proceed slowly, and the feasibility of local green gas is questioned. A supply chain of decentralised green hydrogen production from locally generated electricity (PV or wind) and decentralised green gas production from locally collected biomass and biological power-to-methane technology was analysed and compared to a green hydrogen scenario. We developed a novel method for assessing local options. Meeting the heating demand of households was constrained by the current EU law (RED II) to reduce greenhouse gas (GHG) emissions by 80% relative to fossil (natural) gas. Levelised cost of energy (LCOE) analyses at 80% GHG emission savings indicate that locally produced green gas (LCOE = 24.0 €ct kWh−1) is more attractive for individual citizens than locally produced green hydrogen (LCOE = 43.5 €ct kWh−1). In case higher GHG emission savings are desired, both LCOEs go up. Data indicate an apparent mismatch between heat demand in winter and PV electricity generation in summer. Besides, at the current state of technology, local onshore wind turbines have less GHG emissions than PV panels. Wind turbines may therefore have advantages over PV fields despite the various concerns in society. Our study confirms that biomass availability in a dedicated region is a challenge.
Energy efficiency, greenhouse gas reduction and cost price of a green gas supply chain were evaluated. This supply chain is based on co-digestion of dairy cattle manure and maize, biogas upgrading and injection into a distribution gas grid. A defined reference scenario reflects the current state of practice, assuming that input energy is from fossil origin. Possible improvements of this reference scenario were investigated. For this analysis two new definitions for energy input-output ratio were introduced; one based on input of primary energy from all origin, and one related to energy from fossil origin only. Switching from fossil to green electricity significantly improves the energy efficiency (both definitions) and greenhouse gas reduction. Preventing methane leakage during digestion and upgrading, and re-using heat within the supply chain show smaller improvements on these parameters as well as on cost price. A greenhouse gas reduction of more than 80 % is possible with current technology. To meet this high sustainability level, multiple improvement options will have to be implemented in the green gas supply chain. This will result in a modest decrease of the green gas cost price.
Dit project richt zich op de ontwikkeling van de biotechnologische en chemische procesvoering om op basis van mycelium een alternatief voor leer te produceren. In vergelijking met leer is het voordeel van mycelium dat geen runderen nodig zijn, de productie kan plaatsvinden onder industriële condities en met gebruik van reststromen, de CO2 uitstoot alsook hoeveelheid afval verlaagd wordt, en het gebruik van toxische stoffen zoals chroom wordt vervangen door biobased alternatieven. In het project zullen de procescondities worden bepaald die leiden tot de vorming van optimaal mycelium. Daartoe zullen twee verschillende schimmels worden gekweekt in bioreactoren bij de Hogeschool Arnhem Nijmegen (HAN), waarbij specifiek de effecten van de procescondities (temperatuur, pH, shear, beluchting) en de samenstelling van het kweekmedium op groei van het mycelium en materiaal eigenschappen zullen worden onderzocht. De meest optimale condities zullen vervolgens worden opgeschaald. Op het op deze wijze verkregen materiaal zal Mylium BV een aantal nabehandelingsstappen uitvoeren om de sterkte, elasticiteit, en duurzaamheid van het product te vergroten. Daartoe worden biobased plasticizers, cross-linkers en/of flexibility agents gebruikt. Het resulterende eindproduct zal middels specifiek fysieke testen vergeleken worden met leer alsook worden voorgelegd aan mogelijke klanten. Indien beide resultaten positief zijn kan het betreffende proces na het project verder worden opgeschaald voor toepassing naar de markt.
De innovatiewerkplaats Campus Design (CD) richt zich op de duurzame ontwikkeling (SDG) van de campus door middel van praktijkgerichte oplossingen en onderzoek. Vanuit het lectoraat Facility Management van de Hanze, werkt CD samen met kennis- en onderwijsinstellingen, overheden en het bedrijfsleven, bijvoorbeeld om de kwaliteit, gastvrijheid en inclusiviteit te verbeteren zodat iedereen zich welkom voelt op de campus. CD streeft naar een betere aansluiting tussen de ruimte en organisatie op de campus; ook de vergroening en biodiversiteit rekenen we daartoe. Dit doen we door praktijkvragen van onderwijsinstellingen en het bedrijfsleven te koppelen aan praktijkgericht onderzoek van onze senior-onderzoekers, onderzoekers, docenten en studenten, onder meer in architectuur, facility management, gastvrijheid, kunsten en vastgoed. Onze multidisciplinaire aanpak is zeer actiegericht; we willen de campuspraktijk écht veranderen en laten zien dat het betaalbaar is én werkt. We zorgen er dus voor dat oplossingen niet alleen theoretisch en empirisch uitstekend onderbouwd zijn, maar vooral ook praktisch toepasbaar en bewijsbaar beter. Door de goede samenwerking met onze partners, genereert CD oplossingen die onderwijsinstellingen inspireren en hen helpen de SDG te implementeren.
PBL is the initiator of the Work Programme Monitoring and Management Circular Economy 2019-2023, a collaboration between CBS, CML, CPB, RIVM, TNO, UU. Holidays and mobility are part of the consumption domains that PBL researches, and this project aims to calculate the environmental gains per person per year of the various circular behavioural options for both holiday behaviour and daily mobility. For both behaviours, a range of typical (default) trips are defined and for each several circular option explored for CO2 emissions, Global warming potential and land use. The holiday part is supplied by the Centre for Sustainability, Tourism and Transport (CSTT) of the BUas Academy of Tourism (AfT). The mobility part is carried out by the Urban Intelligence professorship of the Academy for Built Environment and Logistics (ABEL).The research question is “what is the environmental impact of various circular (behavioural) options around 1) holidays and 2) passenger mobility?” The consumer perspective is demarcated as follows:For holidays, transportation and accommodation are included, but not food, attractions visited and holiday activitiesFor mobility, it concerns only the circular options of passenger transport and private means of transport (i.e. freight transport, business travel and commuting are excluded). Not only some typical trips will be evaluated, but also the possession of a car and its alternatives.For the calculations, we make use of public databases, our own models and the EAP (Environmental Analysis Program) model developed by the University of Groningen. BUAs projectmembers: Centre for Sustainability, Tourism and Transport (AT), Urban Intelligence (ABEL).
