Hybrid power systems are based on renewable energysources and especially on photovoltaic and wind energy systems.Software package is used to analyze measuring data for windspeed and solar radiation of two locations in Palestine(Ramallah and Nablus). Results of analysis illustrate thatenergy density available in wind for Ramallah site is about 2008 kWh/ mP2.year, while it is 927 kWh/m2 .year for Nablus site. Thedaily average of solar radiation intensity on horizontal surfaceis about 5.4 kWh/m2 .day. A Matlab software package is used to simulate different scenarios of operation of the hybrid system by making energy balance calculations on an hourly basis foreach of the 8760 hours in a year. This enable to choose the appropriate sizes of the different components for the most optimum scenario. The optimization is based on cost of generation. Results of the simulation illustrate that the most economic scenario is the scenario that uses a hybrid systemmainly dependent on wind. Cost of energy (COE) in thisscenario is 1.28 NIS/kWh(͠ 0.35 $/kWh). Other scenariosdependent on wind-diesel hybrid system, PV-diesel hybrid system, wind stand-alone system, PV stand-alone system, or diesel only, give results of COE greater than this value. It wasconcluded that none of the hybrid system scenarios analyzedcould be justified to replace purchasing of electricity from thegrid where the COE is 0.70 NIS/kWh(0.19 $/kWh).
In this study the effects of root and foliar treatments of marrow
plants with cadmium and lead solutions on the growth of the various
parts of plant (roots, stem, leaves and fruits) have been studied.
Growth inhibition of the various parts of treated plants has been
compared with each other and for the two types of treatment. The
toxicity of cadmium on the growth of plant has been compared with the
toxicity of lead on the various parts of plants treated by root or by
foliar‐treatment with metal ions.
Cadmium and lead uptake by
plants and the distribution of this uptake between the various parts of
treated plants have been determined and commented on.
Percentages of cadmium or lead taken by plant from the total amount of cadmium or
lead added during treatment have been calculated and found to be very
small. This percentage has been found to be higher in foliar‐treated
plants and from dilute solutions than in root‐treated plants and from
more concentrated cadmium or lead solutions.