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<jats:p>The residential load is one of the largest consumers of the electric energy in Libya that could be supplied by renewable energies. Renewable energy technologies and systems can be a good solution to build “Zero Energy Buildings”. A zero-energy house is proposed for Maqrun city. It is intended to use wind turbine with batteries as a storage system to supply electric energy demand for this house.The intended house average daily electric energy demand is estimated to be 35 kWh/day. Two WECS were selected to supply the energy demand each of size 6 kW. The energy produced by the selected wind energy conversion system (WECS) is about 23,894 kWh/yr and the expected capacity factor at the site is about 23%. Modeling of energy demand of the house and simulation of its performance was performed using excel sheets and HOMER software.</jats:p>

<jats:p>&#x0D; &#x0D; &#x0D; &#x0D;  &#x0D; &#x0D; &#x0D; Libya is suffering from freshwater shortage as most of its land is semi-arid to arid with very low precipitation rates and too limited fresh water sources. Libya is in one of the driest regions of the world with an annual rainfall ranging from just 10 mm to 500 mm, and only 5% of its land receives more than 100 mm annually. This review summarizes the most important published studies related to solar thermal desalination research in Libya. Brief description of the most thermal desalination technologies is also presented. The study has shown that only few in-completed pilot projects were carried-out for desalination using renewable energy. The research activities in the field of using renewable energy especially solar thermal energy to desalinate water are limited and do not give a comprehensive idea on the potential of different thermally driven solar desalination technologies. However, most of the recent pilot studies refer to using CSP desalination in providing most of the future water demand in Libya by 2035. A lot of efforts need to be done to carry-on a genuine research to put strategic plan to tackle the deficit water issue in Libya through using desalination driven by conventional and renewable energies.&#x0D; &#x0D; &#x0D; &#x0D; </jats:p>

<jats:p>In this study, wind speed and direction data provided by Meteoblue AG-Switzerland as hourly time-series for 16 years from 2000 to 2015 for selected three cities in Gaza Strip, are used directly to evaluate the wind energy in the three selected sites which are geographically presenting the entire Strip. Jabalia is located in the North of Gaza Strip, Deir-albalah in the Middle and Rafah in the South. The wind rose diagrams have been depicted by using WRPLOT view 7.0.0 (wind rose plots for meteorological data from Lake Environmental, 2011). The statistical analysis of the data shows that; Rafah city is the first candidate to establish a wind farm in the entire Palestinian territory. The reason that, Rafah has the highest wind energy potential than the other sites. The second reason is that Rafah is located on the border crossing to Egypt, which facilitates the transfer of machinery, experts, and reduces transport and communication expanses. In addition to low population density, which increases the economic feasibility of utilizing wind energy at this location for remote area applications. The analysis has been done for a large types of wind turbines types. Gamesa G128-4.5 WT, which is manufactured for classes I and II wind speeds with low cut-in speed, was selected for our project. The estimated annual energy is 15,962 MWh/turbine, with an average utility factor of 40.4%; to cover the shortage of 200 MW we need to 110 WTs. The required area for the wind farm is estimated to be 43 km2.</jats:p>

<jats:p>This review paper focuses on documenting and studying published papers and works in the field of solar heating and cooling air space in residential buildings. The goal of this survey and documentation is to find out the most important flashing results and conclusions specifically in fields of using solar energy for space heating, cooling and ventilation of local residential buildings in Libya. This covers using active and passive solar systems in, achieving thermal human comfort in such buildings leading to reduce electrical energy consumption. This paper also concentrates on applying energy efficiency measures in buildings; planning, design, and construction stages with the use of the principles of energy conservation in buildings. There are several studies comparing traditional with modern house designs in several local cities including both famous old cities of “Ghadames” and “Gharyan”. Several conclusions and recommendations are summarized within the text of this paper.</jats:p>

<jats:p>This paper, illustrates a design and simulation of a solar powered absorption refrigeration system preserves food above freezing point. The main system is modified from a commercial conventional system located at Tajoura, Libya. The target is to design and operate the system at high solar fraction and efficiency. The simulation is performed by TRNSYS to evaluate the annual thermal performance of the solar system that consists of 50-kW absorption chiller producing cold for three refrigerated rooms. The model could be classified into two main parts; refrigeration load model and solar powered refrigeration system model. The results demonstrated that the optimum system achieves 51% solar fraction consists of 48 m2 of high performance evacuated tubes solar collectors and 5000-litre thermal storage tank, in order to power a 50-kW absorption chiller that offers cold for three refrigerated rooms of vegetables.</jats:p>

<jats:p>Libya is facing an increasing deficit in electrical energy supply which needs great efforts to find new and renewable alternative sources of power. Solar thermal electricity is one of the most promising and emerging renewable energy technologies to substitute the conventional fossil fuel systems. A review of the research literature of solar thermal electricity in Libya is presented in this article. The state of the art of these technologies including design, operation principles and global market is demonstrated. Detailed reviews of research activities that have been conducted by Libyan researchers or institutions are presented. It has been found that Libya as a country needs a strategic plan and more research efforts in order to adopt these new technologies and put them in production mode.</jats:p>

<jats:p>A mathematical model of the bubble pump is established by employing the governing equations; the continuity, momentum and energy equations. The model was used to evaluate the performance of the pump under different geometrical and operational conditions. Different parameters including the pump tube diameter, the pumping head, and solar heating input were considered in the analysis. The flow rates of both phases (liquid and vapor) were predicted for each set of parameters. Methanol was used as the working fluid. The performance is presented for a number of different scenarios. The flow was found to be increased with both larger diameters and low static heads, while it has a roughly sine curve with the heat input. A set of results show that for a tube diameter of 10 mm and pumping head of 450 mm, increasing the heat input from 300 W to 500 W increases the mass flow rate of vapor from 0.04 kg/sec to 0.08 kg/sec, while the liquid flow increases from 0.075 kg/sec to 0.22 kg/sec, respectively. Generally, the results of this study were found to be in fair agreement with published results.</jats:p>

<jats:p>The main objective of the present paper is to compare nine different cell temperature models available in the literature with data measured under real Derna city climatic conditions (a semi arid climate) for month of August. The study focuses on a comparison of nine theoretical models to calculate the cell temperature based on the experimental measurements such as the ambient temperature, irradiance, and wind speed in some of the models. The presently used models are explicit, depending on the easily measurable parameters and of wide applicability. Six statistical quantitative indicators are used to evaluate the cell temperature models analysed, namely, R2, RMSE, RRMSE, MAE, MBE and MARE. The cell temperature correlations presently studied, first order linear models depending on the ambient temperature, solar irradiation incident on the panel and voltage output, provide the most accurate cell temperature estimations at Derna city climatic conditions.</jats:p>

<jats:p>Electricity plays an important role in the contemporary life, and it has become indispensable nowadays. Reducing the peak electricity load and increasing the load factor have been considered as one of the main tasks that have to be accomplished by both electricity generation-side and demand-side managements.The residential sector of Libya consumes over 31% of the total sold electricity, and 29.8% of that is delivered to the electric water heating load. This is an inefficient way of electricity utilization. Usually, the electricity supplier in Libya used to increase the local generation capacity or import electricity from neighboring countries. Both solutions did not resolve the problem. This work attempts to investigate the effect of replacing electric water heaters in the residential sector of Libya by solar water heaters on reducing the electricity peakload and increasing the load factor. The results show that on average 3% of the peak load demand can be saved. This is equivalent to 149.5 MW of reduced power. The study also revealed that the annual amount of energy saved is up to 2.55TWh, and the load factor is improved by 2% (i.e. from 65% to 67%). This saved energy is equivalent to a power plant with a nominal capacity of 448 MW considering a load factor of 0.65</jats:p>

<jats:p>The prediction of solar radiation is very important tool in climatology, hydrology and energy applications, as it permits estimating solar data for locations where measurements are not available. In this paper, an adaptive neuro-fuzzy inference system (ANFIS) is presented to predict the monthly global solar radiation on a horizontal surface in Libya. The real meteorological solar radiation data from 5 stations for the period of 1982 - 2009 with diffrent latitudes and longitudes were used in the current study. The data set is divided into two subsets; the fist is used for training and the latter is used for testing the model. (ANFIS) combines fuzzy logic and neural network techniques that are used in order to gain more effiency. The statistical performance parameters such as root mean square error (RMSE), mean absolute percentage error (MAPE) and the coeffient of effiency (E) were calculated to check the adequacy of the model. On the basis of coeffient of effiency, as well as the scatter diagrams and the error modes, the predicted results indicate that the neuro-fuzzy model gives reasonable results: accuracy of about 92% - 96% and the RMSE ranges between 0.22 - 0.35 kW.hr/m2/day</jats:p>