Commoning Cars

By Aron Petau • 7 minutes read •

Commoning cars

Project Update 2025

System Upgrade: The monitoring system now runs on a Raspberry Pi Zero, chosen for its improved energy efficiency. The system only operates when sufficient solar power is available, making it truly self-sustainable. This update has significantly reduced the project's power consumption while maintaining all monitoring capabilities.

TCF Project Brief

This project was conceptualized during the 2023 Tangible Climate Futures workshop.

Project Lead: Aron Petau
Contact: aron@petau.net

View Live Project Data

Abstract

Private cars represent one of the most significant privatizations of public space in modern cities.
What if we could transform these private spaces into public resources?
What if cars could contribute to public infrastructure instead of depleting it?

With the rise of electric vehicles and solar technology, cars can be reimagined as decentralized power stations and energy storage units. This project explores this potential by converting my personal vehicle into a public resource, equipped with:

This artistic experiment tracks the vehicle's location, energy input/output, and public usage patterns. By making this data publicly available, we can quantify the untapped potential of private vehicles and challenge conventional notions of ownership and public resources.

Introduction

After seven decades of car-centric urban development, many cities find themselves at an impasse. The traditional solution of building more roads has proven unsustainable, both environmentally and socially. While one project cannot solve this systemic issue, we can experiment with alternative approaches to existing infrastructure.

This project proposes a different perspective: instead of viewing cars solely as transportation, what if they could serve as nodes in a public infrastructure network? By transforming private vehicles into shared resources, we might begin to address both our environmental challenges and our need for more equitable public spaces.

Experiment

Data Collection & Analysis

A year of private vehicle usage data reveals patterns of underutilization and potential energy sharing opportunities. While the monitoring system's solar dependency means some data gaps exist, the available information clearly demonstrates the untapped potential of private vehicles as public resources.

Technical Implementation

The monitoring system consists of:

The system monitors:

Public Services

The project currently offers two main public services:

  1. Free WiFi Hotspot

    • Public access point similar to café WiFi
    • Powered by solar energy
    • Uses existing mobile data plan
    • Automatic power management

  2. USB Charging Station

    • External weatherproof USB port
    • Solar-powered with battery backup
    • Smart power management to prevent battery depletion
    • Available during daylight hours

Public Communication

To make these services discoverable:

Challenges & Considerations

Scale & Efficiency

While a car's roof provides limited space for solar panels compared to buildings, this project isn't about maximizing solar generation. Instead, it focuses on utilizing existing infrastructure more effectively. Many vehicles, especially camper vans, already have solar installations. By sharing these resources, we can improve their utilization without additional environmental impact.

Two main legal considerations shape the project:

  1. Network Liability

    • German law holds network providers responsible for user traffic
    • Investigating legal protections similar to those used by public WiFi providers
    • Implementing appropriate usage policies and disclaimers

  2. Privacy & Security

    • Balancing public access with system security
    • Protecting user privacy while maintaining service transparency
    • Ensuring responsible resource sharing

Privacy & Data Ethics

The project raises important privacy considerations that we're actively addressing:

  1. Data Collection

    • Location tracking is limited to vehicle position only
    • Network usage is monitored anonymously (device count only)
    • No monitoring of user traffic or personal data
    • Regular data purging policies

  2. Data Publication

    • Aggregated statistics to protect user privacy
    • Delayed location data release
    • Focus on system performance metrics
    • Transparent data handling policies

Security Considerations

The public nature of this project introduces several security challenges:

  1. Physical Security

    • Protected charging ports to prevent tampering
    • Automatic circuit protection
    • Limited battery access to prevent depletion
    • Regular security audits

  2. Network Security

    • Isolated public WiFi network
    • Limited bandwidth per user
    • Automatic threat detection
    • Regular security updates

Further Reading

For more context on the broader implications of this project:

Data Analysis & System Optimization

Our year-long data collection has revealed several key insights about the system's performance and potential:

  1. Energy Generation Analysis

    • Hourly solar generation data with geocoding
    • Temperature correlation tracking
    • Actual vs. potential energy generation comparison
    • Detailed usage patterns

  2. System Losses We've identified two primary types of efficiency losses:

    • Storage limitations when batteries reach capacity
    • Environmental factors such as urban shading and suboptimal parking positions

  3. Performance Optimization Current efforts focus on:

    • Improving energy storage efficiency
    • Optimizing parking locations based on solar exposure
    • Balancing public access with system capabilities

Technical Challenges

Through implementation, we've addressed several key technical concerns:

  1. Power Management

    • Smart charging controls prevent battery depletion
    • Circuit protection against electrical tampering
    • Automated system monitoring and shutdown

  2. User Experience

    • Clear usage instructions via QR code
    • Real-time system status indicators
    • Automated notifications for vehicle movement

  3. Data Quality

    • Redundant data collection for intermittent connectivity
    • Local storage for offline operation
    • Automated data validation and cleaning

Future Implications

This project raises important questions about urban infrastructure:

  1. Scaling Potential

    • Application to public transport fleets
    • Integration with existing urban power networks
    • Policy implications for vehicle regulations

  2. Grid Integration Electric vehicles could serve as distributed energy storage, helping to:

    • Stabilize power grid fluctuations
    • Reduce the need for constant power plant operation
    • Support renewable energy integration

  3. Social Impact

    • Reimagining private vehicles as public resources
    • Creating new models of shared infrastructure
    • Building community resilience through distributed systems

For detailed technical specifications and implementation guidelines, please refer to our project documentation.

The Messy Reality

Let's be honest about the challenges of turning a private car into a public power station:

The Tech Stuff Sometimes the internet drops out, the solar panels get shaded by buildings, and the whole system goes to sleep when there's not enough sun. It's a bit like having a temperamental coffee machine that only works when it feels like it. But that's part of the experiment - working with nature's rhythm instead of fighting it.

Making it Public How do you tell people "Hey, my car is actually here to help you"? It sounds weird, right? We're so used to seeing cars as private spaces that need protection. I'm trying to flip that around with some simple signs and a QR code, but it's definitely a mental shift for everyone involved.

Safety First (But Not Too Boring) Sure, we need to make sure nobody can drain the battery completely or short-circuit the USB ports. But we also need to keep it approachable. No one wants to read a manual just to charge their phone. It's about finding that sweet spot between "please don't break it" and "yes, this is for you to use."

The Bigger Picture Here's the fun part: what if we could turn every parked car into a tiny power station? Instead of just taking up space, these machines could actually give something back to the city. It's a bit utopian, maybe even a bit silly, but that's what art projects are for - imagining different possibilities.

Think of it as a small experiment in making private things public again. Yes, cars are still problematic for cities, but while they're here, maybe they can do more than just sit around looking shiny.