The cost of large-scale PV plant has dropped dramatically in recent years.
These reductions are driven in large part by economies of scale as well as technological improvements and lower-priced panels manufactured in China. The result is falling solar panel prices, inverter prices, and “soft costs” related to sales, permitting inspection, connection to the electricity grid, and the profit margins of retailers and installers.
In this scenario an important key factor to reduce costs and to be more competitive in the different tenders around the world is the reduction of the installation time.
Taking into account that large scale PV power plants are under construction in different countries in the world often in challenging environmental conditions (i.e. desert) and that installation is currently completely manual with potential risks for the operator health, it is under analysis and study the adoption of automatic systems to use during the erection.
The largest part of large scale PV plants under construction use the tracker technology with the goal to follow the sun during the day and to increase the production of PV modules.
The main models of trackers selected by Enel Green Power for his project until now are characterized as follow (rif. Att.1):
- Primary structure composed by piles supporting a torque tube
- Secondary structure composed by module supports (brackets)
The movement of the tracker is realized with a motor-actuator system led by a control system.
The framed PV modules anchoring system to the module supports (rif. Att.2), is currently mainly based on two different systems:
Both abovementioned elements connect the frame of the panel to the module support profile (usually the bracket).
The module support profile is designed to fulfill the following requirements:
- Support the PV modules
- Resist to the wind loads acting on the tracker structure
- Allow the manual installation as easy as possible
The implementation of these requirements will lead to module supports with very small thickness and significant flexibility. This situation is advisable for the manual installation, but it does not match the requirement of automatic installation, which needs high stiffness of module supports and small installation tolerances allowed.
Enel Green Power is looking for a modules-to-structure coupling system fit for purpose to be used with robotic solution installing the modules.
Any proposed solution should address the following Solution Requirements:
1. The proposed solution must allow the robot to install the PV modules automatically, without using bolting or riveting, or any other consumable, minimizing the movements and actions to be done as well as installation time (i.e.: the robot arm has to place in the right installing position the PV modules and then has to be allowed to fix them easily, for example with a slight movement and a light pressure on the modules)
2. The proposed solution must allow the robotic system to install the PV modules on the tracker. In particular, geometrical and dimensional tolerances (in the order of 1/2 cm) of the tracker should be compensated.
3. The proposed solution should be integrated as much as possible in the module support profile of the tracker, minimizing additional assembly activities on site, like bolting and riveting, coupling, jointing. No special process (e.g. welding) is allowed on site
4. The proposed solution has to guarantee the modules to be fixed without clearences (gap) between PV module frame and tracker secondary structure.
5. The proposed solution has to guarantee the respect of mechanical stress level allowed for the modules, during the installation phase and the operational one, according to the maximum load foreseen for the module (see Att. 3), in order to avoid damages (e.g. to the frame, the glass, the cells and the interconnections).
6. The proposed solution has to guarantee the respect of mechanical strengths required against external forces to properly fix the modules at the tracker (i.e. mechanical stress due to the action of the wind) in all the direction (i.e. the sliding effect has to be taken into account) See Att. 3
7. The proposed solution has to be fit for purpose for the entire lifetime foreseen for the trackers and the modules (i.e. 25 years) in harsh environmental condition; in particular, in case non-metallic materials are proposed, the ageing effect has to be taken into account
8. The proposed solution has to guarantee the electrical continuity between the modules metal frame and the structures
9. The proposed solution should allow the manual dismounting of the modules from the structure. The dismounting phase must not damage the modules and the structures. If possible, this phase should not require any special tool.
10. The proposed solution might include slight design change regarding the secondary structures (only the module supports). The tracker weight increase, transportation constraints, production technologies and overall costs, have to be assessed and reduced as much as possible
11. The proposed solution must consider the robotic solution has only one arm able to manipulate the PV modules from the upper side. No additional arms and no different manipulation approaches are possible
12. The proposed solution must be economically efficient when considering all costs (e.g. cost of device, installation of the device on the tracker, installation of the modules on the tracker, maintenance costs) in order to be amenable to mass deployment in PV solar plants. Additional costs when compared to the current market solutions should not be greater than 1 USD per panel.
13. The solution must be easy to install also manually. No maintenance should be required.
14. The proposed solution must be easily adaptable to typical solar trackers available on the market
15. The solution must use no toxic chemicals or have any negative impact on the environment
16. The proposed system should offer the Seeker “freedom to practice” or be available for potential licensing. There should be no third party patent art preventing the use of specific equipment and materials for their commercial application.
The submitted proposal should include the following:
- Detailed description of the proposed solution that can meet the above Solution Requirements.
- Rationale as to why the Solver believes that the proposed solution will work. This rationale should address each of the Solution Requirements described in the Detailed Description and should be supported with any relevant examples, cost analysis, simulations or technical assessment as deemed relevant by the Solver.
- Data, drawings, case studies, patent and journal references or any additional material that supports the proposed solution.
Details of trackers and modules to be considered are available in the attachments 1, 2 and 3.
- For support you can contact OpenInnovabilityemail@example.com -
- deadline extended -