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Energy self-sufficiency and sustainability in a defined neighbourhood: Bio-methanation to green gas can outperform green hydrogen

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.

Targeting Energy Management

Energiebeheer gericht aanpakken, Het analyseren van doelstellingen, resultaten en impacts van energie- en broeikasgasbeheersprogramma’s in bedrijven (met een samenvatting in het Nederlands): De wereldwijde uitstoot van broeikasgassen moet drastisch worden teruggebracht om de mondiale stijging van de temperatuur tot het relatief veilige niveau van maximaal 2 graden Celsius te beperken. In de komende decennia zal de verbetering van de energie-efficiëntie de belangrijkste strategie zijn voor het verminderen van de energiegerelateerde uitstoot van broeikasgassen. Hoewel er een enorm potentieel is voor verbetering van de energie-efficiëntie, wordt een groot deel daarvan nog niet benut. Dit wordt veroorzaakt door diverse investeringsbarrières die de invoering van maatregelen voor energie-efficiëntie verbetering verhinderen. De invoering van energiemanagement wordt vaak beschouwd als een manier om dergelijke barrières voor energiebesparing te overwinnen. De invoering van energiemanagement in bedrijven kan worden gestimuleerd door de introductie van programma's voor energie-efficiëntie verbetering en vermindering van de uitstoot van broeikasgassen. Deze programma's zijn vaak een combinatie van verschillende elementen zoals verplichtingen voor energiemanagement; (ambitieuze) doelstellingen voor energiebesparing of beperking van de uitstoot van broeikasgassen; de beschikbaarheid van regelingen voor stimulering, ondersteuning en naleving; en andere verplichtingen, zoals openbare rapportages, certificering en verificatie. Tot nu toe is er echter beperkt inzicht in het proces van het formuleren van ambitieuze doelstellingen voor energie-efficiëntie verbetering of het terugdringen van de uitstoot van broeikasgassen binnen deze programma's, in de gevolgen van de invoering van dergelijke programma's op de verbetering van het energiemanagement, en in de impact van deze programma's op energiebesparing of de vermindering van de uitstoot van broeikasgassen. De centrale onderzoeksvraag van dit proefschrift is als volgt geformuleerd: "Wat is de impact van energie- en broeikasgasmanagement programma’s op het verbeteren van het energiemanagement in de praktijk, het versnellen van de energieefficiëntie verbetering en het beperken van de uitstoot van broeikasgassen in bedrijven?".

Voluntary carbon offsets a solution for reducing tourism emissions? assessment of communication aspects and mitigation potential

Contrary to most sectors, to date the tourism and aviation industries have not managed to level off greenhouse gas emissions. Moreover, effective mitigation through technological innovation or structural and behavioural change cannot be expected shortly. Airlines and tourism companies appear to use carbon offsetting as a last resort. However, offsetting is generally acknowledged as a second-best solution for mitigating emissions, after reducing energy use. This paper seeks to determine the mitigation potential of voluntary carbon offsetting by comparing public and industry awareness of climate change and aviation emissions, and attitudes to various mitigation measures with relevant online communication by 64 offset providers. Methods were a literature review and online content analyses. Overall, the gaps that were identified between awareness, attitude and actual behaviour are not bridged by provider communication. From this perspective, the mitigation potential of voluntary carbon offsetting for achieving reductions of tourism transport emissions is estimated as low. The same conclusion is reached by comparing carbon dioxide volumes of flight offsets with actual air travel emissions. Current sales of flight offsets compensate less than 1% of all aviation emissions.

The challenge of implementing green gas into the gas supply

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.

Decarbonizing the international shipping industry

Ship-source greenhouse gas (GHG) emissions could increase by up to 250% from 2012 levels by 2050 owing to increasing global freight volumes. Binding international legal agreements to regulate GHGs, however, are lacking as technical solutions remain expensive and crucial industrial support is absent. In 2003, IMO adopted Resolution A.963 (23) to regulate shipping CO2 emissions via technical, operational, and market-based routes. However, progress has been slow and uncertain; there is no concrete emission reduction target or definitive action plan. Yet, a full-fledged roadmap may not even emerge until 2023. In this policy analysis, we revisit the progress of technical, operational, and market-based routes and the associated controversies. We argue that 1) a performance-based index, though good-intentioned, has loopholes affecting meaningful CO2 emission reductions driven by technical advancements; 2) using slow steaming to cut energy consumption stands out among operational solutions thanks to its immediate and obvious results, but with the already slow speed in practice, this single source has limited emission reduction potential; 3) without a technology-savvy shipping industry, a market-based approach is essentially needed to address the environmental impact. To give shipping a 50:50 chance for contributing fairly and proportionately to keep global warming below 2°C, deep emission reductions should occur soon.

Tourism and climate change mitigation : methods, greenhouse gas reductions and policies