STUDY ON TESTING FEASIBILITY OF SOLAR ENERGY IN THE PALESTINIAN TERRITORIES

Transcription

1 STUDY ON TESTING FEASIBILITY OF SOLAR ENERGY IN THE PALESTINIAN TERRITORIES FALLING WITHIN THE FRAMEWORK OF THE EXTRAORDINARY FINANCIAL ASSISTANCE OF THE CZECH REPUBLIC TO THE PALESTINIAN TERRITORIES FOLLOWING THE DECISION OF THE GOVERNMENT OF THE CZECH REPUBLIC NO. 81/28 OF 27 TH JUNE 28 Photovoltaic Installation 2,16kWp Bethlehem 4th Quartal and Final Annual Report April 29 March 21 Electromechanical Engineering Co. Ltd., Bethlehem, Palestine SUNNYWATT CZ s.r.o., Prague, Czech Republic

2 Basic project data Type of engineering work: Aim of the project: Photovoltaic system 2,16kWp with meteorological sensors and datalogger - To test a grid connected photovoltaic system in the meteorological conditions of Palestine and collect data for a precise design of grid connected and off-grid systems in this location - To establish cooperation between a Czech and Palestinian company in field of renewable energy and independent local energy production Designer and developer: Building site: Positioning: Elemco Electromechanical Engineering Co. Ltd. in partnership with SUNNYWATT CZ s.r.o. Czech Republic Bethlehem, Palestine Rooftop system Part: Final Annual Report: April 29 March 21 Author of the report: Ing. Petr Wolf SUNNYWATT CZ s.r.o. Contact: Sunnywatt CZ Jizerská 322/ Prague 9, Czech Republic info@sunnywatt.cz Contact persons: Ing. Petr Wolf wolf@sunnywatt.cz tel: (responsible project coordinator) Ing. Miroslav Váša m.vasa@centrum.cz tel: (head of the company) Elemco Electromechanical Engineering Co. Ltd. Al Madaress Str., Bethlehem P.O. Box 912 West Bank Palestine Tel: 97 (2) info@elemco.ps elemco_86@yahoo.com Contact person: William Anton Abu Zaoulof tel:

3 1. Basic description In March 29 Czech company Sunnywatt CZ s.r.o. in cooperation with Palestinian Elemco Electromechanical Engineering Co. Ltd. has mounted a photovoltaic (PV) system on the roof of the building of Elemco company. The main objective of this project was to test how a real PV system behaves in weather conditions of Palestine, collect the data for a precise design of grid connected and off-grid photovoltaic systems and establish cooperation between two companies with experience in electrical engineering, Sunnywatt CZ from Czech Republic and Elemco from Palestine. Before this project there were no real data of such a photovoltaic system available from the Palestinian territory, all designs and analysis had to be based on simulations, which caused problems and uncertainty. Photovoltaic energy can play an important rule in this area in the near future and therefore before starting big project it is important to have experience in local conditions with these systems. The system was designed as a small scale PV system equipped with a monitoring unit in order to collect data for a long term observation and evaluation in local climatic conditions. All parts of used equipment have been mounted and tested in Prague by company Sunnywatt on outdoor conditions before delivery to Palestine to avoid potential problems by setting the devices into operation. Collecting of the data started on The input data for this report are from dates This report is the final report after one year of collecting the data and monitoring the system. This annual report can be used as a basic reference for photovoltaic systems that will be used in meteorological conditions of Mediterranean climate with hot and dry summers and cold winters. For these conditions applies most places with similar altitude in the West Bank. Both companies will continue on running the system in order to have a long term evaluation of meteorological conditions and PV system performance. After on year of operation the system is working with no problems or degradation. The effect of aging of the system, especially modules has not been detected and little performance decrease will be probably visible after more years of operation. 2

4 The PV system consists of: PV generator unit - 12pcs PV modules Sunnywatt 18W - Inverter SMA SB 21TL - Construction set - Cabling, switchboards with electrical equipment (fuses, overvoltage protection etc.) Monitoring unit - SMA sensor box - Meteorological sensors (wind speed, ambient temperature, module temperature, irradiance sensor) - Power injector - Sunny WebBox (datalogger, ftp server) - Cabling, switchboards with electrical equipment - Colored IP camera with IR night lighting - Notebook 3

5 kwh W/m2 Daily energy (kwh) 2. 4 th quartal report The 4 th quartal report shows the operation of the system in the period January 21 March 21. Energy output of the system: Daily energy yield (kwh) 35 24, 3 22, 25 2, 2 15 ; 18, 16, 1 14, 5 12, 1, October November December Energy yield per month (kwh) Mean irradiance (W/m2) Energy yield and mean irradiance in observed months 4

6 Energy yield per month (kwh) Energy yield per month Mean irradiance (W/m2) Mean wind speed (km/h) Mean module temperature ( C) Mean ambient temperature ( C) January ,57 179,41 6,2 18,6 14,17 February ,99 195,39 7,85 16,8 12,66 March 21 36,86 228,36 8,69 16,49 11,36 In January we obtained a similar energy yield as in February, in March we already realized increased energy output. Mean temperature increase on solar panels due to irradiation is cca. 5 C. On sunny days in this period the typical ambient air temperatures were 17 C and module temperature 3 C. The low ambient air temperatures result in high efficiency of PV panels in this period. 5

7 Energy yield per month (kwh) 3. Annual evaluation Comparison of annual obtained energy (April 29 March 21) and the estimation using PVGIS Bethlehem - real production (kwh) Bethlehem - PV GIS estimation (kwh) Apr ,91 39 May ,7 345 Jun , Jul , Aug ,9 358 Sep ,6 326 Oct 29 38, Nov ,2 216 Dec , Jan , Feb , Mar 21 36, Annual yield (April 29 - March 21) 375, Apr 29 May 29 Jun 29 Jul 29 Aug 29 Sep 29 Oct 29 Nov 29 Dec 29 Jan 21 Feb 21 Mar 21 Bethlehem - real production (kwh) Bethlehem - PV GIS estimation (kwh) Energy yield and mean irradiance in observed months The really obtained energy from the PV system in Palestine is in all observed months slightly higher than the estimated values using PVGIS. During the observer period (April 29 March 21) the real production was 1,2% above the estimation (3751kWh real, 344kWh estimated). Calculated on 1kWp of installed power we can expect with a PV installation with a high efficiency inverter and small losses in cables etc. the annual yield 1737kWh/kWp. 6

8 Wind speed (km/h) Wind speed (km/h) Wind speed 35, 3, 25, 2, 15, 1, 5,, Mean daily wind speed during one year of monitoring 12, 11, 1, 9, 8, 7, 6, 5, Apr May Jun 29 Jul 29 Aug 29 Sep 29 Oct 29 Nov 29 Dec 29 Jan 21 Feb 21 Mar 21 Mean monthly wind speed during one year of monitoring Mean monthly wind speed varies from cca. 5,6km/h to 1,7km/h. In the summer period the wind blow seem to be more constant, with no big variations. 7

9 Ambient temperature ( C) Module temperature ( C) Temperature 4, 35, 3, 25, 2, 15, 1, 5,, Mean daily module temperature during one year of monitoring ( C) 35, 3, 25, 2, 15, 1, 5,, Mean daily ambient air temperature during one year of monitoring ( C) 8

10 Temperature difference ( C) 12, 1, 8, 6, 4, 2,, -2, Mean daily temperature difference between modules and ambient air ( C) Figure of temperature difference between modules and ambient air shows the temperature increase caused by irradiation. During summer period the mean daily increase is cca. 8 C and is almost constant because the irradiation is stable. In winter time there are more days with cloudy weather and the temperature increase varies more. Mean monthly temperatures during one year of monitoring Mean monthly temperatures of modules and ambient air reach maximum in June, July and August. The reach minimum values in December, January, February and March, in these months they are almost constant. 9

11 :15 1:15 2:15 3:15 4:15 5:15 6:15 7:15 8:15 9:15 1:15 11:15 12:15 13:15 14:15 15:15 16:15 17:15 18:15 19:15 2:15 21:15 22:15 23:15 Temperature ( C) Irradiation (W/m^2) Module temperature ( C) Ambient temperature ( C) Irradiation (W/m^2) One day temperature and irradiation on a clear sunny day in winter ( ) One day temperature and irradiation on a cloudy day in winter ( ) 1

12 :15 1:15 2:15 3:15 4:15 5:15 6:15 7:15 8:15 9:15 1:15 11:15 12:15 13:15 14:15 15:15 16:15 17:15 18:15 19:15 2:15 21:15 22:15 23:15 Temperature ( C) Irradiation (W/m^2) One day temperature and irradiation on a clear sunny day in summer ( ) Module temperature ( C) Ambient temperature ( C) Irradiation (W/m^2) One day temperature and irradiation on a cloudy day in summer ( ) 11

13 Energy yield per month (kwh) Mean irradiance (W/m2) Energy yield per day (kwh) Energy yield Energy yield per day during one year of monitoring (kwh) Apr 29 May 29 Jun 29 Jul 29 Aug 29 Sep 29 Oct 29 Nov 29 Dec 29 Jan 21 Feb 21 Mar 21 Energy production (kwh) Mean irradiance (W/m2) Monthly energy yield and irradiance during one year of monitoring 12

14 Frequency (days per year) kwh/day Daily energy distribution during one year - histogram It is most likely that the energy on a chosen day will exceed 1kWh or more (296 out of 365 days). The most probable case is between 12-13kWh (32% of cases). Energy yield per day versus the mean daily irradiation Daily energy yield corresponds with the daily mean irradiation with little variations caused by temperature and wind. 13

15 Performance factor ( - ) Performance factor Performance factor indicates the relation between the power generated by the system and solar irradiance. It shows how much the system is affected by the temperature, reflectance, losses in cables, inverter etc.,88,86,84,82,8,78,76,74 Apr May Jun 29 Jul Aug Sep 29 Oct Nov Dec Jan 21 Feb Mar Energy yield per day versus the mean daily irradiation The performance factor achieves relatively high values comparing to other PV installations worldwide. The main reasons are high efficient modules, transformless PV inverter with high efficiency and small distances in cables. Also the cooling of modules is very good because it is a rooftop installation on flat roof, so the wind has a high speed and the panels can be effectively cooled. 14

16 4. Conclusion The PV system in Palestine together with the monitoring unit is working without any problems. The obtained data show that the rough estimation of annual energy is close to the really obtained values. The really obtained energy in the period of April-December is cca. 11% above the expected value. The monthly energy yield is in the region of Palestine much better balanced than in middle Europe. This means that in Palestine for example autonomous photovoltaic systems for rural areas can work more balanced and more efficient in the whole year. 15

17 5. Economical aspects This article briefly describes the economical aspects of photovoltaic energy usage in the territories of Palestine. Until now there has been no implementation of a feed in tariff in Palestine. The Israel government has recently introduced fixed feed in tariffs with annual decrease of 4%. The feed in tariff depends on the installed power and for the year 21 is set 1,97,73 NIS / kwh. For renewable energy one can get premium green payment of,44nis/kwh. The photovoltaic system can be therefore simply connected to the grid and deliver all energy to the grid. With the local energy yield of cca. 173kWh / kwp and photovoltaic system costs of cca. 15,5 NIS / Wp we can assume the investment payback time of 4years for middle scale systems. In Palestine, the photovoltaic can be at present time used for own use, to reduce the energy costs for buying electricity. In such conditions, the owner of a PV plant reduces only his own electricity bill, but can not get any extra money for selling the energy to the grid. With the estimated energy costs of about,13 / kwh the investment payback time is 14years. This is only in case that connection to electrical grid is already available. For areas situated far from electrical grids, the situation is completely different and solar energy is fully competitive with other sources of energy. One must decide if to use diesel generator with expensive operation costs or make a connection to the nearest electrical grid or build his own solar photovoltaic system. The photovoltaic energy offers in this case the best option- compared to a typical small diesel generator (1 5kW) the payback time of photovoltaic system is about 3 years. Photovoltaic system is almost maintenance free and running with no exhaust or noise. The Palestinian Territories have practically no energy resources and are nowadays fully dependant on energy source imports. The Palestinian electricity sector suffers from many problems, such as high transmission losses and high electricity prices per kwh. The Palestinian Territories are dependent on the Israel Electric Co. for nearly all of their electrical needs. Seven percent of the Palestinian population is still without access to an uninterrupted electricity service. These problems can be solved with help of new energy sources, such as solar power and wind power. The electricity consumption in Palestinian territories is divided by sectors as follows: Residential 61% Commercial 22% Industrial 9% Others (water pumping, street lighting,.) 8% 16

18 Conclusion On many places in Palestine the photovoltaic energy can be effectively implemented and become local main energy source. With no feed in tariff photovoltaic energy can nowadays be economical efficient only for places far away from electrical grid. On such places off grid (autonomous) photovoltaic systems can be installed. New residential areas or houses using now diesel generators can be equipped with photovoltaic systems that will be economically effective. It will help to the energy independence of the area and protection of the nature. The financial payback time of small photovoltaic autonomous systems is about 3years. To make grid connected photovoltaic systems economically effective, financial support must be implemented. One important reason for this is the effort of reducing the energy dependence on Israel and other countries. For a payback time of 8years and typical prices of electricity,13 / kwh, the feed in tariff of about,22 / kwh should be implemented for selling the energy to the grid. If the producer will use the energy for his own use, the produced energy by photovoltaic system should be awarded by cca.,1 / kwh. Assuming the prices for components for photovoltaic systems and the prices for designing and installation, a grid connected PV system can cost cca. 3 / kwp. An offgrid system will cost about 4 5 / kwp. A typical household can be fully supplied by electrical energy from a 1 3kWp system according to the loads needed. The main advantage is the energy independence, maintenance free operation and high lifetime of the most expensive components (PV panels, more than 25years). Concerning the technology for photovoltaic systems we can recommend using panels with mono or polycrystalline silicon cells. Monocrystalline cell panels have been tested in the 2,16kWp project and have very good annual energy yield. Mono- and polycrystalline technologies are generally considered for having similar behavior. Thin film cells have better temperature behavior but are not a good solution for using in climates with high intensities of direct solar irradiation (Palestine). 17