Search results for "Energy engineering"
showing 10 items of 1099 documents
Boosting Long-Term Stability of Pure Formamidinium Perovskite Solar Cells by Ambient Air Additive Assisted Fabrication
2021
Due to the high industrial interest for perovskite-based photovoltaic devices, there is an urgent need to fabricate them under ambient atmosphere, not limited to low relative humidity (RH) conditions. The formamidinium lead iodide (FAPI) perovskite α-black phase is not stable at room temperature and is challenging to stabilize in an ambient environment. In this work, we show that pure FAPI perovskite solar cells (PSCs) have a dramatic increase of device long-term stability when prepared under ambient air compared to FAPI PSCs made under nitrogen, both fabricated with N-methylpyrrolidone (NMP). The T80 parameter, the time in which the efficiency drops to 80% of the initial value, increases f…
Multiple Scenario Analysis of Battery Energy Storage System Investment: Measuring Economic and Circular Viability
2022
Circular business models for batteries have been revealed in earlier research to achieve economic viability while reducing total resource consumption of raw materials. The objective of this study is to measure the economic performance of the preferred business model by creating different scenarios comparing second life (spent) and new battery investment for seven different European regions and four energy management strategies. Findings reveal levels of economic ability for a total of 34 scenarios simulated, including direct savings per kWh, a total change in energy costs per year, battery charge/discharge cycles, and comparative breakeven analyses. Regional effects are also measured based …
The Influence of Behavioral Factors on Insurance Decision – A Romanian Approach
2013
Abstract Although the classical economic theory postulates that individuals should make perfectly rational choices that take into account all the available information, I will present, in the following, the action of behavioral factors on the decisions regarding the insurance against certain events. I will analyze the elements that determine a person who should be covered against a risk, not to buy insurance and the reverse situation when, although the likelihood of the event is reduced, a person will secure against the damage(s) caused by it. In this paper I developed a general approach of the behavioral factors with specific reference to the Romanian market .Finally, I will suggest the in…
Life Cycle Energy and Environmental Assessment of the Thermal Insulation Improvement in Residential Buildings
2021
The refurbishment of the building stock is a key strategy towards the achievement of the climate and energy goals of the European Union. This study aims at evaluating the energy and environmental impacts associated with retrofitting a residential apartment to improve its vertical envelope thermal insulation. Two insulation materials, stone wool and cellulose fibers, are compared. The life cycle assessment methodology is applied assuming 1 m2 of retrofitted vertical envelope as functional unit. Moreover, to estimate the net energy and environmental benefits achievable in the retrofitted scenario compared with the non-retrofitted one, a second analysis is performed in which the system boundar…
Effect of Tire-Char Ash on the Extent of Synergy during CO2 Cogasification with Hydrochar from Potassium-Rich Coconut Fiber
2020
The influence of inherent tire char ash during co-gasification with coconut hydrochar prepared at different intensities was investigated by thermogravimetric analysis to ascertain the extent to which synergistic interaction, reactivity, and activation energy reduction were altered. High-ash tire tread (TT) and low-ash sidewall (SW) both exhibited enhanced synergy, reactivity, and activation reduction upon co-gasification with hydrochars; however, the extent of promotion was more pronounced in SW-hydrochar blends. This difference was caused by the inhibiting nature of TT inherent ash, particularly the role of Si-containing compounds. Inhibition in TT-hydrochar blends was mainly due to the pr…
Real time analysis of Escherichia coli biofilms using calorimetry
2008
Abstract Microbial communities grow more stably when they are associated to surfaces or organized in aggregates. This advantage of biofilms is technically exploited for the degradation of xenobiotics or in biocatalysis, where the fixed biomass has the added advantage of easier separation of excreted products. Whereas the biothermodynamic analysis of growth and product formation of suspended cells is developing fast, there are only few reports on the calorimetric analysis and biothermodynamic interpretation of biofilm evolution. Experiments illustrate the ability of calorimetry to monitor the physiological state of biofilms in real time. Sessile cells of Escherichia coli DH5α DSM 6897 were s…
Thermophilic hydrogen production from cellulose with rumen fluid enrichment cultures: Effects of different heat treatments
2011
Elevated temperatures (52, 60 and 65 °C) were used to enrich hydrogen producers on cellulose from cow rumen fluid. Methanogens were inhibited with two different heat treatments. Hydrogen production was considerable at 60 °C with the highest H2 yield of 0.44 mol-H2 mol-hexose -1 (1.93 mol-H2 mol-hexose-degraded-1) as obtained without heat treatment and with acetate and ethanol as the main fermentation products. H2 production rates and yields were controlled by cellulose degradation that was at the highest 21%. The optimum temperature and pH for H2 production of the rumen fluid enrichment culture were 62 °C and 7.3, respectively. The enrichments at 52 and 60 °C contained mainly bacteria from …
An Energy Blockchain, a Use Case on Tendermint
2018
The recent advances in distributed energy systems require new models for exchanging energy among prosumers in microgrids. The blockchain technology promises to solve the digital issues related to distributed systems without a trusted authority and to allow quick and secure energy transactions, which are verified and cryptographically protected. Transactions are approved and subsequently recorded on all the machines participating in the blockchain. This work demonstrates how users, which are nodes of the energy and digital networks, exchange energy supported by a customized blockchain based on Tendermint. We focus on the procedures for generating blocks and defining data structures for stori…
Gir boplikt lavere boligpriser?
2020
Siden 1974 har norske kommuner hatt adgang til å innføre boplikt for eiendommer som er eller har vært i bruk som helårsbolig. Ordningen har helt siden den ble innført, vært svært omstridt. Vi undersøker hvordan boplikt påvirker boligprisene. Geografisk avgrenser vi oss til kystkommuner på Sørlandet, der mange som har sin faste bopel andre steder i landet, etterspør fritidsbolig. Uten boplikt kan helårsboliger bli kjøpt opp for å bli brukt som fritidsboliger. Den empiriske analysen, basert på data fra fire sørlandskommuner, hvorav den største kommunen, Arendal, opphevet boplikten i 2014, viser at prisene i kystsonen økte da boplikten ble opphevet.
Road Thermal Collector for Building Heating in South Europe: Numerical Modeling and Design of an Experimental Set-Up
2022
The combination/integration of renewable energy and storage systems appears to have significant potential, achieving high-energy results with lower costs and emissions. One way to cover the thermal needs of a building is through solar energy and its seasonal storage in the ground. The SMARTEP project aims to create an experimental area that provides for the construction of a road solar thermal collector directly connected to a seasonal low-temperature geothermal storage with vertical boreholes. The storage can be connected to a ground-to-water heat pump for building acclimatization. This system will meet the requirements of visual impact and reduction of the occupied area. Nevertheless, sev…