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Energy security is one of the main drivers of energy policies. Understanding energy security implications of long-term scenarios is crucial for informed policy making, especially with respect to transformations of energy systems required to stabilize climate change. This paper evaluates energy security under several global energy scenarios, modeled in the REMIND and WITCH integrated assessment mod
Fuel cells are promising with advantages of higher energy conversion efficiency and lower emissions of SOX, NOX, and CO2 than conventional power systems. Solid oxide fuel cell (SOFC) is a high temperature fuel cell, which operates at 873-1273 K. This allows SOFCs to operate with different types of fuels from both fossil and renewable sources because of their general higher tolerance to contaminant
Photosynthetic microbial fuel cells (PMFCs) are an emerging technology for renewable solar energy conversion. Major efforts have been made to explore the electrogenic activity of cyanobacteria, mostly using practically unsustainable reagents. Here we report on photocurrent generation (≈8.64 μA cm(-2)) from cyanobacteria immobilized on electrodes modified with an efficient electron mediator, an Os(
We investigate a cooperative communications scheme with N parallel relays, where both the transmissions from the source to the relays and from the relays to the destination use fountain codes. Receiver for codes can accumulate mutual information, while traditional energy collection methods, such as repetition or cooperative space-time codes, only accumulate energy. As a consequence, using fountain
The 2007/08 food price crisis brought unprecedented international attention to the relationship between food and biofuels, and their competition over land. In this article we sought to understand how the international policy framing of the nexus of food, fuel and land has developed since the food price crisis. We undertook an analysis of major reports, since the crisis, by three international poli
It is expected that fuel cells will play a significant role in a future sustainable energy system. They are energy efficient, fuel can be produced nearly locally and, when a renewable fuel such as ethanol, methanol and biogas is used, there are no net emissions of greenhouse gases. Fuel cells have during recent years various progresses, but the technology is still in the early phases of developmen
A new technology has emerged the last decade, based on a new group of materials; Soft Magnetic Composites (SMC), instead of laminated steel that facilitates production of products with more integrated, smaller, lighter, less costly and highly efficient electromagnetic machines. The application of this technology is a change of paradigm regarding integrated design and energy efficiency. This articl
The use of biofuels for road transport in Sweden has increased during the past 10 years as policymakers stimulate demand in response to concerns about climate change. Using a supply chain approach, this paper analyses: (i) existing biofuel supply chains in Sweden (biogas, biodiesel and bioethanol) in terms of security of supply, and (ii) possibilities to achieve synergies between implementation of
Popular Abstract in Swedish Energianvändningen i världen måste minska drastiskt inom en snar framtid för att därmed minska utsläppen av växthusgaser och bromsa klimatförändringarna. Energi och handlande med energikällor har även blivit nationella säkerhetsfrågor. Inom Europeiska Unionen används ungefär 40% av den totala energianvändningen i byggnader, vilket innebär ungefär 36% av det totala koldiThe use of energy is a major global issue both according to climate changes but also in the aspect of national safety tied to the trade with energy sources. Of the total energy use in the member states of the European Union, about 40% is used in residential and commercial buildings. Passive houses are one way to reduce the energy use in buildings and at the same time keep a good indoor comfort. Th
Caldicellulosiruptor owensensis strain OLT (DSM 13100) is an obligately anaerobic, extreme thermophilic bacterium that is capable of utilizing a broad range of carbohydrates and producing H2 as a metabolic by-product. The performance of C. owensensis on glucose and xylose was analyzed in lab-scale bioreactors to assess its potential use in biohydrogen production. Acetate, H2, and CO2 were the main
In this paper, a novel membrane reactor (MR) for methanol steam reforming is modeled to produce fuel cell grade hydrogen, which can be used as the inlet fuel for a later developed 500-W horizon polymer electrolyte fuel cell (PEFC) stack. The backpropagation (BP) neural network algorithm is employed to develop the mapping relation model between the MR's prime operational parameters and fuel cell ou
Internal combustion engine is a developed and established technology whichcontributes largely to the transportation of goods and people. In one hand, theburning of fossil fuels is the main reason for the combustion engines to beconsidered unsustainable while on the other hand, the combustion behaviour ofrenewable fuels is not fully understood yet. This lack of knowledge is morepronounced when it c
This paper explores the history of wind power technologies and the integration of wind energy in the Danish energy system. It does so focusing particularly on historical events, socio-cultural and socio-political changes and priorities that were important on this technological journey. From the first primitive wind turbines in the late 1800s, to the world wars, through the energy- crisis in the 70
This article studies the potential combination of direct ground cooling (DGC) with district heating (DH) and ground source heat pumps (GSHP) to compare the required borehole depths and needed drilling areas. It also examines two different borehole sizing approaches to optimize investment costs and drilling areas. The results show that the required borehole depths in most cases are shorter for the
Naturally occurring plant cellulose, our most abundant renewable resource, consists of fibers of long polymer chains that are tightly packed in parallel arrays in either of two crystal phases collectively referred to as cellulose I. During mercerization, a process that involves treatment with sodium hydroxide, cellulose goes through a conversion to another crystal form called cellulose II, within
Accelerated by the harms and depletion risk of fossil fuels, transition to low-carbon or renewable fuels have become an urgent need for combustion engines to decarbonize transport sectors. Natural gas-diesel dual-fuel combustion is a promising method to achieve these goals by allowing the usage of natural gas in diesel engines. However, this concept has drawbacks of low combustion efficiency, high
The Constrained Application Protocol (CoAP) is a standard communication protocol for resource-constrained devices in the Internet of Things (IoT). Many IoT deployments require proxies to support asynchronous communication between edge devices and the back-end. This allows (non-trusted) proxies to access sensitive parts of CoAP messages. Object Security for Constrained RESTful Environments (OSCORE)
Isobutanol, one of the four isomers of butanol (C4H9OH), possesses some favorable properties that make it an attractive fuel for internal combustion engines. For instance, when compared to ethanol, isobutanol features a higher heating value and lower hygroscopicity (which prevents corrosion and enables it to be transported via pipelines). Moreover, its addition to gasoline does not distort the fue
