Search results for "Water production"
showing 6 items of 6 documents
THE RELATIONSHIP BETWEEN DIFFUSE AND TOTAL SOLAR RADIATION IN COMPUTER SIMULATION OF SOLAR ENERGY SYSTEMS
1978
ABSTRACT The diffuse to total radiation correlation developed by Liu and Jordan [1] was tested for three Italian locations. An acceptable agreement was found between the regression lines in [1] and the ones found for two of the three locations. Using measured hourly values of total solar radiation on a horizontal surface, the corresponding hourly values of total solar radiation on an inclined surface at 45° facing south were computed with both the Liu and Jordan and the Loudon [6] method for estimating the diffuse radiation. Results show that approximately the same degree of accuracy in the prediction is achievable with both methods and that the difference between the measured total monthly…
Modeling of the process of moisture loss during the storage of dried apricots
2011
[EN] Moisture content is a reference parameter for dried food because the growth of most microorganisms is inhibited below certain water activity levels. In addition, it has a determining influence on the evolution of important parameters, such as color and flavor, and on other properties and deterioration reactions, such as texture, oxidation processes and nutritional value. During the storage of some dried fruits, moisture is produced due to Maillard reactions and exchanged with the surrounding environment through the packaging. The evolution of dried foods during their shelf life depends on the storage conditions. The aim of this study is to analyze the evolution of the moisture content …
Eco-Efficiency of the English and Welsh Water Companies: A Cross Performance Assessment
2021
Analyzing costs and greenhouse gas (GHG) emissions could be of great importance for the water utilities to supply water services in a healthy and sustainable manner. In this study, we measured the eco-efficiency of several water utilities in England and Wales by incorporating GHG as an undesirable output. For the first time, we evaluated the eco-efficiency of the water production process using robust cross-efficiency data envelopment analysis (DEA) techniques. The further use of clustering and regression techniques allowed us to better understand the drivers of eco-efficiency. The results showed that the mean eco-efficiency of the water sector was 0.748, which indicates that costs and GHG e…
Determining Optimal Seasonal Irrigation Depth Based on Field Irrigation Uniformity and Economic Evaluations: Application for Onion Crop
2016
The crop water production function (WPF), representing the relationship between crop yield and seasonal irrigation water, is a useful tool for irrigation planning purposes. The objective of the paper is to propose a methodology to evaluate the optimal seasonal irrigation depth based on the crop production function, the field distribution uniformity, and economic considerations. An extended unpublished database experimentally obtained on the onion crop on the island of Kula, Hawaii, was initially used to assess the crop WPF. The combination between the crop WPF and the model representing the field distribution uniformity allowed determining the area subjected to underirrigation and overirrig…
Electrical hybrid heat pumps assisted by natural gas boilers: a review
2022
In this paper, a comprehensive review is performed on hybrid systems using electrical Heat Pumps for Heating, Ventilation & Air Conditioning systems and Domestic Hot Water production using case studies from 2016 to 2022. This work particularly focuses on studies that investigated systems with electrical Heat Pumps assisted by a gas boiler. Some studies that considered the exploitation of renewable energy sources, but not as a whole sub-stitute for fossil sources, have also been included. In particular, the analysis investigated the layouts of the systems by considering the type and the size of the components, the control methods applied (by distinguishing rule-based control methods and …
Alternative energy storage options for heat pump water heater coupled with photovoltaic plant for domestic hot water production
2019
The present work relies on the topic of energy storage for Heat and Electricity applied to Heat Pump Water Heaters coupled with photovoltaic plants for Domestic Hot Water production. The main idea is to evaluate the possibility to exploit the water tank as heat storage for the produced photovoltaic energy and, where appropriate combined with electrical storage. For this reason, two heat pumps with different volume size have been chosen and smart control strategies have been applied while monitoring the water temperature in the tank. Calculations account on tapping profile inferred from monitored data of a representative end-user in a Mediterranean small island. Results show how the combinat…