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UIC 90930, EREX, and energy metering
Energy savings become much more concrete once traction energy is measured and settled in a clear way. That changes how DAS value is discussed.
Published: April 20, 2026
TopicsUIC 90930EREXEnergy meteringTraction energyCO2 reduction
Why metering matters
- Metering makes traction energy visible in a way that operators can actually track.
- That makes it easier to connect driving behaviour to cost and performance.
- It also makes the DAS value discussion less abstract.
What changes once energy is visible
- When the energy signal is weak, savings claims are hard to prove.
- When the energy signal is measured, eco-driving results are easier to test and compare.
- That helps operators justify rollout with real numbers instead of only broad expectations.
What DAS can support
- DAS can support smoother acceleration, better coasting, and less wasted braking.
- Under suitable conditions, that can still sit in the guarded 5 to 15 percent range often used in the sector.
- Metering helps show whether those changes are actually appearing in service.
Limits
- Metering does not create savings on its own.
- Results still depend on timetable constraints, operation type, driver behaviour, and training quality.
- CO2 statements also depend on traction type and local power mix, so they should be made carefully.
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