Wasted Watts Tracker: measuring real energy losses in cycling with RTK GPS

Wasted Watts Tracker

System for measuring energy losses in cycling

The Wasted Watts Tracker is a complete system designed to measure and analyze a cyclist’s energy losses in real-world riding conditions. It is based on an architecture combining two onboard modules, a smartphone application, and access to an RTK GPS data correction service.

The system quantifies Wasted Watts, meaning the energy that is lost and converted neither into speed nor altitude gain, and displays them with an almost immediate analysis delay during the ride. The Wasted Watts Tracker is intended for cyclists who want to optimize their position and equipment choices based on data measured on open roads.

What the Wasted Watts Tracker includes

The Wasted Watts Tracker is a complete system, designed to operate as a coherent whole. Each component plays a specific role in measuring energy losses in real-world conditions.

Two onboard modules mounted on the bike

Rear module

• • Core of the system.
  • Captures the power produced via the bike’s power meter.
  • Measures energy variation linked to speed and altitude.
  • Calculates raw Wasted Watts, corresponding to watts that are actually lost.

Front module

• • Measures the true air speed encountered by the cyclist.
  • Transmits these data to the rear module.
  • Enables conversion of raw Wasted Watts into normalized Wasted Watts, independent of wind conditions.

The two modules operate jointly and are designed for use on open roads.

Dedicated smartphone application

The system relies on a smartphone application that ensures:

• communication between the modules,
• reception and transmission of RTK GPS correction data,
• visualization of Wasted Watts during the ride.

The smartphone acts as a data gateway, without adding complexity for the cyclist.

RTK GPS correction service (subscription)

The operation of the Wasted Watts Tracker is based on RTK GPS technology.

• Access to differential corrections is provided through a data correction service available by subscription.
• This service delivers centimeter-level accuracy for position, altitude, and gradient.
• This precision is essential to reduce data smoothing and make measurements usable in near real time.

The correction service is a constitutive part of the product.

How the Wasted Watts Tracker works during a ride

The Wasted Watts Tracker integrates into a standard ride, without complex protocols or ideal conditions to be met.

Installation and startup

• Installation of the rear module and front module on the bike.
• Launch of the smartphone application.
• Initialization of communication between the modules, the power meter, and the RTK GPS correction service.

Data acquisition

During riding:

• The power meter measures the mechanical energy delivered at the pedals.
• The rear module measures speed, altitude, and gradient with centimeter-level precision.
• The front module measures the true air speed encountered by the cyclist.

All data are temporally synchronized by the system.

Calculation of Wasted Watts

• Application of the cyclist’s energy balance equation.
• Comparison between produced energy and the variation of stored energy.
• Calculation of Wasted Watts, corresponding to lost energy.

Depending on the configuration used, the cyclist can visualize raw Wasted Watts or normalized Wasted Watts, with an analysis delay of only a few seconds.

Data display

Data can be viewed:

• on the smartphone application,
• or on a compatible GPS head unit (list of compatible models to be provided).

The cyclist can adjust position, compare postures, or test equipment directly during the ride.

Compatibility & ecosystem

The Wasted Watts Tracker integrates into the cyclist’s existing ecosystem.

• Interface with the bike’s power meter.
• Data display on smartphone or compatible GPS head unit.
• Use of low-bandwidth mobile connectivity for receiving RTK corrections.

A list of recommended power meters and compatible GPS head units will be communicated.

What the cyclist can measure concretely

The Wasted Watts Tracker quantifies real energy losses related to the cyclist’s choices.

• Wasted Watts: energy lost that is converted neither into speed nor altitude gain.
• Riding position: measurable impact of postural adjustments.
• Equipment: comparison of helmets, clothing, wheels.
• Rolling resistance: influence of tires, pressure, and surface.
• Specific configurations: luggage and load impact in gravel or long-distance riding.

Each modification results in a measurable change in Wasted Watts.

Who the Wasted Watts Tracker is for

The Wasted Watts Tracker is intended for cyclists focused on optimization and analysis.

• Road cyclists looking to optimize position and equipment.
• Triathletes and time trial specialists seeking to analyze the efficiency of sustained positions.
• Gravel and long-distance cyclists wanting to measure the impact of load configurations.

It targets riders who want to go beyond power output alone.

Why measuring Wasted Watts changes performance

Measuring Wasted Watts shifts performance analysis:

• from energy production,
• to real-world movement efficiency.

This approach allows cyclists to:

• objectify sensations,
• compare configurations,
• optimize performance without increasing physiological load.

Conclusion

The Wasted Watts Tracker offers a different approach to cycling performance. Designed as a complete system combining hardware, software, and service, it brings road-based analysis that was previously limited to laboratory environments. It is intended for cyclists who want to understand what truly limits their progress and optimize performance through efficiency.

Frequently Asked Questions – Wasted Watts Tracker

What are Wasted Watts in cycling?

Wasted Watts refer to the portion of energy produced by the cyclist that does not translate into forward speed or altitude gain. They represent losses caused by aerodynamic drag, rolling resistance, posture inefficiencies and external conditions. Measuring Wasted Watts makes it possible to evaluate real-world efficiency rather than power output alone.

How does the Wasted Watts Tracker measure energy losses on the road?

The Wasted Watts Tracker combines power data, centimeter-accurate RTK GPS measurements and true air speed data. By applying the cyclist’s energy balance equation, it compares produced energy with actual changes in speed and altitude to calculate the watts that are effectively lost during real riding conditions.

Why is RTK GPS necessary for measuring Wasted Watts?

RTK GPS provides centimeter-level accuracy for position, altitude and gradient. This precision is essential to reduce data smoothing and noise, allowing energy losses to be calculated and displayed with only a few seconds of delay. Without RTK correction, real-time analysis of Wasted Watts would not be reliable.

Can Wasted Watts be displayed during the ride?

Yes. Depending on the configuration, Wasted Watts can be viewed in near real time either on the dedicated smartphone application or on a compatible GPS head unit. This allows cyclists to adjust their position, test equipment or compare postures directly during the ride.

Who is the Wasted Watts Tracker designed for?

The Wasted Watts Tracker is designed for cyclists focused on optimization and analysis, including road cyclists, triathletes, time trial specialists and gravel or long-distance riders. It is intended for athletes who want to go beyond power data and understand how efficiently their energy is converted into motion.