Solar-Powered Charging Station Design for Events

Job ID: 38949110

Budget: $250 – $750 USD

PLEASE READ THESE DETAILS THOROUGHLY BEFORE BIDDING. I DO NOT ENTERTAIN TIMEWASTERS WHO ENTER A BID TO WIN AND THEN SEEK TO INCREASE THE COST LATER ON. i AM AS OPEN AS POSSIBLE ON THE BID REQUEST.

Tender Invitation Document

Project: Design and Prototype of a Solar-Powered Multi-USB Charging Station

Objective

We invite bids from experienced electronics engineers or engineering firms to design, prototype, and deliver a fully functional, cost-optimized 20-port USB charging station. The solution must prioritize low manufacturing costs, fast charging capability, and robust commercial-grade durability while adhering to the outlined requirements. The winning bid will receive full technical documentation upon project award.

Scope of Work

The successful bidder will:

Design and Develop:

A single-sided PCB for a 20-port USB charging station incorporating all specified features.

A firmware system that enforces a 6-month license validation system via USB Port 1.

Prototype and Test:

Deliver a fully operational prototype, including all hardware, enclosure, and software.

Ensure that the prototype meets all functionality, safety, and durability requirements.

Provide Documentation:

A detailed schematic diagram.

Production-ready Gerber files for PCB manufacturing.

A complete Bill of Materials (BOM) with cost estimates.

Testing and calibration reports verifying the prototype’s functionality.

Key Design Requirements

Power System

Dual Power Input:

Solar Input: 12V from an 80W solar panel, with integrated charge controller and priority logic.

DC Input: 12V external power supply, with solar taking priority when available.

Battery Backup:

SLA Battery: 12V 50Ah, providing 2-3 hours of charging at full load.

DC-DC Conversion:

Centralized step-down conversion (12V to 5V) with >85% efficiency.

USB Ports

Configuration:

10 fast-charging ports (QC 2.0/3.0).

10 standard 5V/2.4A ports.

Port Placement:

All ports must be accessible from one side of the device

Durability:

Heavy-duty USB-A ports capable of 10,000+ insertion cycles.

License Validation System

License Control:

6-monthly validation codes entered via USB Port 1.

Device locks after five incorrect code entries or upon license expiry.

Code Management:

Devices individually pre-programmed with 20 sequential codes (10 years of use).

Permanent activation code option for specific customers.

Tamper Resistance:

Design to prevent bypassing of license enforcement.

Indicators and Feedback

LED Indicators:

LEDs:
Green LED for normal operation.
Green LED Flash green for cherging
Red LED for battery flat or out of licence
Red LED for license issues (flashing faster as expiration approaches).
Use an NPN transistor to drive LEDs based on MCU output.
Flashing Red: License code required (increasing frequency approaching expiration).
Solid Red: License expired.

Cooling and Enclosure

Cooling:

Passive cooling with heat sinks on key components.

Enclosure or electronics:

Approximate dimensions: 30 x 50 x 25 cm.( negotiable)

Firmware and Features

Firmware:

Handles license validation, timer logic, and fast charging protocols.

Allows firmware updates via USB Port 1.

Charge Management:

Logs the number of charges provided within the license period.

Solar Panel Specifications

Must support charging of a 12V 7Ah battery with 3.5 hours of sunlight per day in temperate zones.

Panel size and power rating to be optimized for this requirement.

Budget and Timeline

Budget:

Target per-unit manufacturing cost (excluding solar panel an battery): £20.

Prototype development budget to be included in the bid. Working prototype is to be supplied by designer. Supply of all prototype components by designer.

Timeline:

Submission of schematic, PCB design, and BOM: 2 weeks from project start.

Fully assembled prototype delivery: 4 weeks from project start.

Tender Submission Requirements

Experience:

Provide examples of similar low-cost electronics projects.

Demonstrate expertise in PCB design, microcontroller programming, and solar power systems.

Technical Approach:

Describe the approach to achieve cost optimization and robustness.

Highlight any proposed innovations or enhancements.

Quotation:

Detailed breakdown of costs for design, prototyping, and documentation.

Development Timeline:

Include a timeline with key milestones and deliverables.

Evaluation Criteria

Cost-effectiveness of the proposed solution.

Demonstrated experience and technical capability.

Adherence to project timeline and milestones.

Quality and robustness of the proposed design approach.

Note: Full technical documentation and IP details will only be shared with the selected bidder after project award.

Submission Deadline: 27Feb 2025

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