Material Insights · Understanding the Material World

Regenerative braking and motion recovery: Economics and contracts

Nearly free when built in, costly when bolted on

What this tab covers Economics and commercial structures: levelised cost of the recovered energy against the fuel it avoids, host-site risk, and service models such as heat-as-a-service.

Where the drive is already bidirectional the extra cost is small and paybacks are short. Stand-alone retrofits depend on duty and on fuel or power prices.

Levelised cost of heat or avoided cost

Mixed

For a diesel RTG with storage, the study estimated about 78 MWh a year of recoverable energy per crane. That would save about 32,600 litres of fuel and about GBP 19,600 a year. GKN claimed a 3 to 4 year payback for Gyrodrive on buses. In the Otis example, ReGen saves about 2,933 kWh a year (calculated). At the USD 0.10 per kWh price implied by the example, that is only about USD 293 a year (calculated), so lift regeneration pays mainly in busy, tall buildings.457

RTG fuel saving with storage about 32,600 L/y, about GBP 19,600/y per crane5 Gyrodrive payback 3-4 years (company claim)7 Otis example saving about 2,933 kWh/y, about USD 293/y (calculated)4

Host factory credit risk

Favourable

Hosts are transit agencies, port operators, bus companies and building owners. Their assets move with them, and they rarely close the way a single factory does. The main stranding risk is technical. Diesel-hybrid add-ons such as flywheels or RTG storage lose their purpose when the fleet switches to battery-electric, which has regeneration built in.1

Heat-as-a-service and ESCO models

Mixed

Most regeneration is bought as part of the vehicle or drive. Reversible substations are a utility-style infrastructure play. Alstom has sold 136 Hesop units and 110 are in service, in London, Panama, Riyadh, Hamburg, Dubai, Sydney and Hanover. This pass found no sourced shared-savings contracts for regenerative braking.3

Hesop units sold / in service 136 / 110 (2025)3

Sources

  1. FOTW #1360: A typical EV is 87%-91% efficient compared to 30% for a conventional gasoline vehicle US Department of Energy, Vehicle Technologies Office, 2024
  2. Capturing wasted energy in our cities (Hesop reversible substations) (company press release) Alstom, 2025
  3. ReGen drive (product brochure, UK) (vendor claims) Otis
  4. Analysis of energy usage for RTG cranes (Papaioannou et al.), Energy 125, accepted manuscript Elsevier (repository copy, Manchester Metropolitan University), 2017
  5. Gyrodrive hybrid technology first to make economic sense to bus operators (company claims as reported) Transport Engineer