PV power plant installation system with dual axis solar tracking
Innovative Design Robust framework provides zero swinging of PV modules. Strength calculations according to Eurocode 1,3. Hydraulic motion system provides reliability, endurance, zero maintenance and failsafe operation. Hot dip galvanized metal parts, guarantee protection against rust. Built-in lightning protection system. Accuracy of sun observation using astronomical algorithms. Protection against theft ensured by mechgrip. Increased Return On Investment Additional yield of up to 40% compared with fixed installations. Increased NPV of up to 50% for a typical power plant. Cost Effective Solution Economies of scale on materials and on site works due to the small number of pieces per installation. Less on site work due to high degree of standardization and pre- assembly of equipment. (wires, inverters, controls etc) Flexibility Simple and quick installation with high degree of standardization (plug & play). Ready made parts for assembly, with no need of specialized personnel and sophisticated equipment. Compatibility and combination with all available types of PV modules and inverters Optimization of land and possibility of parallel use. Safety Central meteorological station provides active safety. Separate hydraulic circuit provides passive safety. Fully autonomous operation of each tracker. Integrated solution Versions of the basic model including additional features (cables, inverters, control panels, distribution boards etc.) Environmental responsibility and nature protection with paral lel profit increase.
ATLAS SOLAR TRACKER IS AN INNOVATIVE PRODUCT, DESIGNED AND DEVELOPED BY MECHATRON SA, UTILISING ITS LONG TERM EXPERIENCE IN SUCCESSFUL IMPLEMENTATION OF DEMANDING INDUSTRIAL AUTOMATION PROJECTS. THE MAXIMIZATION OF PRODUCED ENERGY OUTPUT IN COMBINATION WITH THE LOW INITIAL INVESTMENT COST INCREASE COMPARED WITH FIXED INSTALLATIONS, MULTIPLY THE BENEFITS PROVIDED BY ATLAS SYSTEM, NECESSITATING IT IN ALL MODERN PV POWER PLANTS. ATLAS SYSTEM CAN ACHIEVE UP TO 40% MORE OUTPUT POWER THAN FIXED TILT SYSTEMS. IT ENSURES THAT THE PV PANELS ARE OPTIMALLY ORIENTATED TOWARDS THE SUN, CONVERTING EFFICIENTLY DIRECT AND INDIRECT SOLAR RADIATION INTO ELECTRICITY. atlas is a dual axis solar tracking system that has been specially developed to provide an intelligent pv power plant solution. pv modules, inverters and other materials from a variety of manufacturers are combined easily, to provide a solution which is far more standardised than any alternative in the market.
SECURITY The metal part of Atlas system was designed and its strength was estimated according to the specifications of Eurocode 3 (EC3/1993). The foundation of the system was laid according to KOS-2000, the new regulation on concrete constructions. In case that, for any reason, PV panels stay in the vertical position, the system withstands exposure to a combination of severe forces (storm with reference wind speed 135 Km/h, snow, etc) just like a house, a warehouse or a huge road signboard (Eurocode 1). Active Safety: When wind speed exceeds 70 km/h, the system automatically takes the horizontal position. Passive safety: Moreover a special safety circuit has been incorporated into the hydraulic control system. In case of destruction of the system controller or breakdown of the Electricity Grid (which mainly happens in case of extreme meteorological phenomena), the Safety Circuit leads automatically to the horizontal position, which is achieved because of the eccentric position of the axis of horizontal rotation with respect to the centre of weight of the frame of the panel.
ROBUSTNESS The frame is constructed in such a way as to minimize swinging. Hence in extreme wind speeds, the PV module surface stays in horizontal position to avoid transverse and torsional vibrations. Vibrations of this kind are common among flat frames and produce fatigue loads. Furthermore, in case of resonance, vibrations can also lead to the destruction of the motion mechanism or even the collapse of the whole frame. The motion system consists of standard industrial hydraulic power units and cylinders. Hydraulic motion, apart from ensuring minimal maintenance costs, leads to system sturdiness and overload capacity, far beyond any alternative solution. 5
FLEXIBILITY The customer specifies the type of the panels to be used and when the trackers are delivered they have the dimensions that suit the specific panels. The photovoltaic modules are bolted on the frame and clamped on it with the special clamping device mechgrip. There is no need for any cut or perforation during the installation. ATLAS SYSTEM IS PRODUCED IN THREE VERSIONS: BASIC SOLUTION WITH THE BASIC EQUIPMENT AND ALL NECESSARY MATERIALS FOR THE ERECTION WIRED SOLUTION WITH WIRING FITTINGS, DISTRIBUTION BOARD AND ANTI-LIGHTNING PROTECTION (DC, AC AND COMMUNICATIONS) TOTAL SOLUTION WITH PV MODULES AND INVERTERS 6
BUILT-IN LIGHTNING PROTECTION Storms and lightning are the main cause of damages to PV installations. Atlas Dual Axis Solar Tracking system incorporates into its basic equipment a lightning protection system consisting of 4 Franklin lightning arrestor rods on each tracker. This is the best way to guard against direct lighting strokes on the tracker, the PV modules and the inverter. A system with lighting arrestors on masts, that provides the same level of protection, requires the dispersion of the masts within the protected area, resulting in shading. In addition, on the distribution board of the wired solution there can be found incorporated on every circuit (AC, DC, communications) surge protection devices, which protect against indirect lightning strokes.
QUALITY RELIABILITY Atlas system is delivered in two parts: the base, which is the bottom part of the tracker, and the mobile frame, that forms the upper part of the system. The base of the tracker is delivered as one piece and incorporates all the equipment that is essential for the operation of the system. In particular: The motion system and the position digital encoders. The hydraulic system filled with oil. AC, DC, signal transfer wiring and PV interconnection in strings. All the mobile cables pass through flexible spirals which are fixed on the main body with special devices in order to avoid damage caused by mechanical fatigue. Inverter, tracker control system, etc. The cables, the control panels and all systems mentioned above, are fitted on the main body of the ATLAS, at the assembly plant and not at the construction site. Furthermore, the main assembly of the ATLAS has been subjected to operation tests before leaving the assembly plant ensuring thus that every subsystem operates smoothly. In this way a high degree of standardization is achieved, avoiding quality compromise which is very likely to be happened when fitting works are done on the PV plant field.
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QUICK AND SAFE INSTALLATION The mobile frame which will bear the PV panels is assembled on four scaffolds of appropriate height so that the personnel can work below at a standing position. Hence, the fitting of the panels on the mobile frame, the wiring connection on strings, the installation of lightning arrestors rods etc, is taking place on the ground. The installation of the ATLAS system requires neither specialized personnel nor sophisticated equipment. Except for a foreman and two experienced technicians, the rest personnel can be non-specialized workers from the local labour market. The electrician s tasks are also limited to the execution of standardized works and checks. The foundation reinforcement, the concrete reinforcement and the anchoring can be executed from any contractor, according to application plans handed to the customer upon order of the equipment. When the field works are completed, a group of 6 workers can assemble, wire and deliver, checked and ready to be connected with the electricity grid, a 100 kwp station within a week. 10
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OPTIMAL LAND USE In order to achieve optimal land use, the length to width ratio of the frame that bears the PV panels is 2:1 approximately. It is worth mentioning that when this ratio tends to 1:1, the land area requirements are 30% higher under the same conditions of shading and covering. 12
PROTECTION AGAINST THEFT The protection of panels against theft is ensured due to: the final height of the construction the difficulty to unscrew or cut of the fixing device of the panel Panel fixing device strength analysis (with FEA) 13
SOLAR TRACKING PRECISION To achieve high solar tracking precision, the Controller of the system solves the astronomical algorithm that describes the relative position of the earth with respect to the sun for the current point in time, date and geographical position. Subsequently, it calculates the real position of the system through incorporated digital encoders and thereafter, by activating the appropriate hydraulic valves, the system moves until the position error is eliminated and the surface of the panel is in vertical position to the sun. The use of the astronomical algorithm for the orientation of the system eliminates the problems of unnecessary movements that usually accompany systems using light sensors. Furthermore, it contributes considerably to maximum solar radiation absorption, as the panels can be placed vertically to the solar rays, even if there is cloudiness, thus taking advantage of the infra red radiation. The precision of position calculation is 0, 75 0 and the frequency of the position error correction can be chosen by the client. If the position of the system is corrected at a 15 minute frequency, the angle between the incident ray of light and the solar panel surface falls within the range of 870 ~ 930, which corresponds to a 99,7% higher energy absorption than the theoretically maximum one. 14
NETWORKING The system includes: Connection with the central meteorological station for the reception of the meteorological data in real time. Incorporated system of telemetry for -Remote tracker monitoring. -Remote manual operation of the trackers. -Recording and collection of data The telemetry helps to achieve maximum system Up time as the problems are reported in real time and are tackled with immediately. 15
ATLAS solar tracker... as dependable as the next sunrise INDUSTRIAL AREA MULTI PROGRESS HEAD OFFICE AND FACTORY: I str., Industrial Area of Heraklion 71 601- Crete - Greece TEL: +30 2810 390 850 FAX +30 2810 390 851 www.atlasolar.com info@atlasolar.com