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This paper proposes a novel deep transfer Q-learning (DTQ) associated with a virtual leader-follower pattern for supply-demand Stackelberg game of smart grid. Each generator and load are regarded as an agent of a supplier and a demander, respectively, in which an economic dispatch (ED) and demand response (DR) can be simultaneously solved by DTQ. To maximize the total payoff of all the agents, a virtual...
In photovoltaic (PV) cells, a large fraction of solar radiation gets converted into heat which raises its temperature and decreases its efficiency. The heat can be extracted by attaching a box containing phase change material (PCM) behind the PV panel. Due to large latent heat of PCM, it can absorb heat without rise in temperature. It will lower down the PV temperature and will increase its efficiency...
A useful map is generated for selecting optimum power generation cycles used for Enhanced Geothermal Systems. Detailed analysis on the thermodynamic performance has been carried out for four power generation systems: single-flash (SF), double-flash (DF), flash-organic Rankine cycle (FORC), and double-flash-organic Rankine cycle (DFORC). Only subcritical ORC cycles with R245fa as working fluid are...
A previously developed procedure to evaluate a biomass plant feasibility has been improved, now considering availability and cost of the biomass resources around the plant's location. The plant is an organic Rankine cycle cogeneration facility located in mainland Spain. All the villages over 15.000 inhabitants have been considered as potential locations. Partial load operation is considered as well...
To avoid a carbon formation in the ethanol steam reforming process from the polymerization of ethylene, a two-step reforming of ethanol via a dehydrogenation reaction and a steam reforming reaction for hydrogen production is proposed in this work. The study of using a CaO sorbent for CO2 capture to enhance the hydrogen production for solid oxide fuel cells is also carried out. Modeling of the two-step...
A novel double-skin roof heat transfer (DSRHT) model is proposed to capture the dynamic thermal behavior of open-ended double-skin roof (DSR). The proposed model is validated against field measurements performed in a 13-storey-tall, naturally-ventilated residential building in Singapore. DSR exhibits dynamic thermal behavior of having an equivalent thermal resistance (or R-value = 1/U-value) 4–5 times...
Large scale deployment of intermittent renewable energy induces new challenges for energy systems. They have to balance the volatile energy consumption with the variable power generation. Thus all other components of a renewable energy system are required to be more flexible than they are at present. Storing surplus energy to meet demands when required is one technical solution of balancing this demand...
This paper deals with the modeling, simulation and implementation of a Claw pole synchronous generator for aircraft applications. The electromagnetics of the machine has been analyzed using Finite Element Analysis (FEA) software. A prototype of the claw pole machine has been developed whose overall performance has been experimentally tested and compared with the simulation results. Finally, the thermal...
This paper proposes a feedforward quasi universal converter for energy harvesters, and uses it to power IoTs (Internet of Things). A typical DC/DC converter uses voltage feedback control or current feedback control. It is difficult to meet its output voltage and power targets and have its input impedance stay as close to the output impedance of the energy source as possible. The proposed feedforward...
The present paper introduces a new diffusion process for the purpose of modeling a Hubbert-type behavior pattern. The main features of the process will be analyzed and the maximum likelihood estimation of the parameters will be carried out through discrete sampling. To this end, a complex system of equations must be solved through numerical procedures, requiring the search for an appropriate initial...
Solar hydrogen is a promising source for sustainable energy. This work presents an effective sunlight spectral management for hydrogen production from hybrid thermo-photovoltaic (TPV) water electrolysis based on optimal power spectral splitting of the concentrated sunlight. In the proposed power spectral shaping scheme sunlight photons are split at every wavelength below the cutoff wavelength of the...
Turbulent flow and convective heat transfer of air inside channel of rectangular cross-section, containing rectangular baffles with inclined upper part planted on the opposite surface of absorber plate is investigated numerically under solar air heater boundary conditions. For a fixed value of heat flux (1000 W/m2) and the range of Reynolds number from 4000 to 18,000, the effect of four baffle blockage...
As a vital part of future low carbon energy systems, storage technologies need to be included in the overall optimisation of energy systems. However, this comes with a price of increasing complexity and computational cost. The increase in complexity can be limited by using simplified time series formulations in the optimisation process, e.g. typical days or multiple time grids. This in turn will affect...
The resource quality and the temporal generation pattern of variable renewable energy sources vary significantly across Europe. In this paper spatial distributions of renewable assets are explored which exploit this heterogeneity to lower the total system costs for a high level of renewable electricity in Europe. Several intuitive heuristic algorithms, optimal portfolio theory and a local search algorithm...
Coal-fired power units are important to stabilize the grid fluctuation especially for the electrical power system with a large proportion of renewable sources. The unit load change speed and range controlled by traditional coordinate control system has become more and more insatiable for the integrations of fluctuant power sources. Condensate throttling is an efficient way to utilize storage energy...
We examine drivers of cost overruns in Norwegian development projects in the oil and gas sector. The multivariate longitudinal econometric analysis employs a unique and detailed dataset consisting of 79 different projects between 2000 and 2013. Among the significant results, we find that the unexpected change in economic activity has a positive effect on the overruns, there is a considerable positive...
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