How occupants respond to building emergencies: A systematic review of behavioral characteristics and behavioral theories

Crystalline silicon photovoltaics are a cardinal and well-consolidated technology for the achievement of energy efficiency goals, being installed worldwide for the production of clean electrical energy. However, their performance is strongly penalized by the thermal drift, mostly in periods of high solar radiation where solar cells reach considerably high temperatures. To limit this aspect, the employment of cooling systems appears a promising and viable solution. For this purpose, four different cooling systems, working on the photovoltaic (PV) panel back surface, were proposed and investigated in an experimental set-up located at the University of Calabria (Italy). Hourly electrical output power and efficiency were provided accounting for different meteorological conditions in several months of the experimental campaign. The results demonstrated that a simple spray cooling technique can provide an absolute increment of electrical efficiency of up to 1.6% and an average percentage increment of daily energy of up to 8% in hot months. More complex systems, based on ventilation or combining spray cooling and ventilation, were demonstrated not to be a viable option for PV performance improvement.

Efficiency Improvement of Photovoltaic Modules via Back Surface Cooling

A Novel Thermal Model for Pv Panels with Back Surface Spray Cooling

三菱重工技報 = Mitsubishi Heavy Industries technical review

A novel thermal model for PV panels with back surface spray cooling

Received: 21 June 2020 Accepted: 18 August 2020 Among the new technologies for the exploitation of the solar source, double-sided photovoltaic panels represent a valid high efficiency solution. These are latest generation photovoltaic panels that allow you to capture solar radiation even from the back and to obtain a greater production of electricity compared to traditional singlesided panels. The performance of the panel is higher, with the consequent possibility of reducing the installation surface. The paper defines a calculation model to analyse performances of a double-sided photovoltaic field, for both type of orientation N-S and E-W, in order to assess the effective increase in performance compared to a traditional system. Panels are equipped with a single-axis solar tracker, which changes their inclination so that they can have the best exposure to solar radiation. The study also focuses on the optimal tracking methodology, in order to reduce the losses caused by shading. The applied technique is that of "backtracking". We have seen that backtracking is not useful for bifacial panels, but only for mono-facial. In the work, a parametric analysis is also conducted to evaluate the increase in efficiency due to distance between rows of panels.

/pdf/performance-analysis-of-a-double-sided-pv-plant-oriented-3gq5do5yvp.pdf

Performance Analysis of a Double-Sided PV Plant Oriented with Backtracking System

Received: 2 July 2020 Accepted: 15 September 2020 In this study, a simplified calculation method to evaluate the thermodynamic performance of two solar tower power plants of 50 MW is proposed. The systems consist in an open air Brayton cycle and a Brayton-Rankine combined cycle. The electricity produced, the average annual efficiency of the heliostats field-receiver system, the efficiency of the thermodynamic cycle and of the entire plant have been determined for both systems. The performances of the two plants have been compared to conventional plants using molten salts. The analysis shows that both systems have better performances than conventional solar tower plants using molten salts. The specific annual electrical energy per square meter of heliostat is higher than that obtained for the plant using molten salts, by 11.5% and 38.7% for the Brayton and the Brayton-Rankine combined cycle respectively. Moreover, an economic analysis has been performed. The results show that a reduction of the Levelized cost of Electricity (LCOE) can be achieved compared to the traditional molten salt plants, with savings of 15% and 13.6% for the Brayton and combined cycle respectively.

/pdf/techno-economic-analysis-of-a-solar-tower-power-plant-with-2wor2x6l0o.pdf

Techno-Economic Analysis of a Solar Tower Power Plant with an Open Air Brayton Cycle and a Combined Cycle - A Simplified Calculation Method

Smart systems based on the Internet of things are being successfully applied in multiple sectors. In this work, the application of the Internet of things to emergency evacuation systems will be tackled. Fixed direction signs represent the current practice in identifying evacuation paths, but they can be misleading or lead evacuees to unsafe areas. Smart evacuation systems can overcome all these issues and allow the shortest and safest path to be determined based on the real time data gathered from sensors. A description of the proposed algorithm is presented. The communication between the different devices and exchange of information are of crucial importance in real-time operations. A reliable evacuation algorithm has to consider if an escape route is no longer usable and promptly provide an alternative path. The evacuees are guided by “smart exit signs” which can change their direction dynamically. Simultaneously, more precise and accurate data is available for the rescuers to ensure a more effective intervention.

Evacuation and Smart Exit Sign System

/pdf/a-calculation-method-to-estimate-the-thermodynamic-cvf2aofjt6.pdf

A Calculation Method to Estimate the Thermodynamic Performance of Solar Tower Power Plants with an Open Air Brayton Cycle and a Combined Cycle

Received: 20 September 2018 Accepted: 29 October 2018 A calculation method for the evaluation of the performance of a 50 MW hybrid solar plant with linear air collectors and an open Joule-Brayton air cycle, equipped with an interrefrigerated compressor, a regenerator and a natural gas combustor has been developed. If the plant is operated each day between sunrise and sunset for an entire year in conditions close to nominal ones, the net electricity produced in one year is 244,000 MWh, the fuel consumption is 34,575 tons of natural gas, the annual average efficiency of solar collectors is 49.8%, the average thermodynamic efficiency of power block is 42.1%, the average conversion efficiency of solar energy to electricity is 20.9%. The saving of fossil fuel due to the employment of solar energy in the hybrid plant is 22%, the cost of electricity produced results to be 8.3 cents$/kWh. This value is competitive with that of other plants using renewable energy.

/pdf/a-simplified-calculation-method-for-the-evaluation-of-the-t6gwhl3uc3.pdf

A simplified calculation method for the evaluation of the performance of a hybrid solar plant with linear parabolic collectors and Joule-Brayton air cycle

Jessica Settino

Papers

Performance Analysis of a Double-Sided PV Plant Oriented with Backtracking System

Techno-Economic Analysis of a Solar Tower Power Plant with an Open Air Brayton Cycle and a Combined Cycle - A Simplified Calculation Method

Evacuation and Smart Exit Sign System

A Calculation Method to Estimate the Thermodynamic Performance of Solar Tower Power Plants with an Open Air Brayton Cycle and a Combined Cycle

A simplified calculation method for the evaluation of the performance of a hybrid solar plant with linear parabolic collectors and Joule-Brayton air cycle