circulation

1. City Background
Bratislava, the capital of Slovakia, is a key political, economic, and cultural hub in Central Europe, with a population of approximately 440,000 (over 700,000 in the metropolitan area). As a compact city, its narrow streets and densely distributed neighborhoods present the following waste management challenges:
- Inefficiency: Fixed-route collection leads to unnecessary pickups of empty bins or delayed servicing of full bins.
- High Costs: Fuel and labor expenses increase due to non-optimized routes.
- Low Recycling Rates: Lack of precise monitoring for waste sorting reduces resident participation.
- Environmental Goals: Compliance with EU Circular Economy Action Plan targets (e.g., 60% municipal waste recycling rate by 2030).

The integration of IoT and RFID technology aims to enable data-driven decision-making for smarter and more sustainable waste management.

2. Solution Design

2.1 Hardware Deployment
- RFID Tags:
- Each waste bin (public/household) is fitted with a passive UHF RFID tag (waterproof, corrosion-resistant), with a unique ID linked to database entries for capacity, type (recyclable/organic/other), and location.
- Low-cost tags (€0.1–0.5 per unit) enable large-scale deployment.
- Readers:
- Vehicle-mounted RFID readers: Waste trucks are equipped with readers (e.g., Impinj R420) and GPS modules, automatically scanning tags (read range up to 10 meters).
- Fixed readers: Installed at waste transfer stations or sorting centers to verify bin collection records.
- Fill-level sensors (optional): Ultrasonic sensors in key bins provide real-time fill data via LoRaWAN.

2.2 Data Flow
1. Tag Scanning: When a truck approaches a bin, the RFID reader captures the tag ID, while GPS logs the location and timestamp.
2. Status Updates:
- If a bin is emptied, the system marks it as "processed"; if fill levels are below a threshold (e.g., <80%), the bin is skipped.
- Sensor data complements RFID scans for dynamic route adjustments.
3. Cloud Analytics: Data is uploaded to a municipal waste management platform (e.g., IBM Maximo or SAP IoT), where AI algorithms:
- Optimize routes: Generate the shortest paths, reducing travel distance (similar to UPS’s ORION system).
- Detect anomalies: Identify bins not serviced for extended periods (potential tag damage or misplacement).

2.3 Pay-as-You-Throw (PAYT) System
- Residential: Household bin tags are linked to user accounts, with collection frequency/weight factored into billing to incentivize waste reduction.
- Commercial: High-frequency scans for restaurant bins trigger extra fees for excess waste.

2.4 Visualization & Decision Support
- Municipal Dashboard: Real-time heatmaps of waste generation, vehicle tracking, and recycling statistics.
- Public App: Residents check collection schedules, recycling guidelines, and report issues (e.g., damaged tags).

3. Expected Outcomes
- Operational Efficiency: Collection routes shortened by 20–30%, cutting fuel costs by over 15% (based on similar projects like Seoul’s RFID system).
- Higher Recycling Rates: PAYT boosts sorting rates by 25–40%.
- Reduced Emissions: Optimized routes lower CO₂ emissions by ~200 tons annually (estimated for a 50-vehicle fleet).

4. Challenges & Mitigation
- Privacy Concerns: RFID tags store only bin IDs, not personal data.
- Tag Durability: Industrial-grade tags are used, with periodic inspections and replacements (automated reports from trucks).

5. Future Expansion
- Drone Inspections: UAVs scan RFID tags in remote areas, supplementing truck coverage.
- Blockchain Tracking: Recycling streams are recorded on-chain for transparency (e.g., plastic sent to recycling plants).

By integrating RFID and IoT, Bratislava is transforming into a model for smart waste management in medium-sized, high-density cities, offering a replicable framework.