Rail Energy – Concept

Rail Energy is a rapidly deployable renewable energy solution for disaster relief, sustainable economic development, remote construction, the military, homeland security – any place energy is needed and railroad tracks reach. Railcar modules with complementary capabilities are connected together to create the capacity and duration required for a specific customer scenario. Then the train is deployed. While in route, energy is being generated and stored in preparation for delivery upon arrival. Once stationary at the service location, energy generation is optimized and additional generation capacity can be configured. After the energy need is satisfied, railcar modules are returned to their travel configurations and deployed to the next location. Customers with a persistent need for deployable renewable energy can purchase their own systems, or Rail Energy can be purchased as a service on a dollars per kilowatt-hour basis.

Key Features

  • Clean renewable energy
  • Mobilized using the rail system
  • Modular and scalable by railcar
  • Configurable interface for different voltages and physical interconnections

Railcar Modules

  • Flow battery storage
  • In-transit solar
  • Stationary solar
  • Micro wind
  • Fuel cell

Flow Battery Storage

Lithium ion battery systems have relatively short runtimes, typically 1-4 hours, which is insufficient for infrastructure-class power. Instead, Rail Energy uses flow battery systems with runtimes in the 6-10 hour range. Vionx Energy is an example of a company that manufactures Vanadium Redox flow battery systems packed into standard containers in 3 megawatt-hour and 100 megawatt-hour capacities.

In-Transit Solar

Solar energy generation is proportional to area, but railcars are constrained in all three dimensions in order to navigate the rail system with tunnels and the like limiting width and overpasses limiting height. So while in transit, the overall dimensions of the solar generation system must remain relatively small. Orientation to the sun is also a key driver of a system’s solar generation capacity, and yet a railcar in motion changes its orientation to the sun’s rays constantly. Therefore, the in-transit solar generation railcar module must be symmetrical around the compass and leverage the vertical axis to increase density. Bifacial solar cells like those from Prism Solar, which are capable of generating energy on both sides, work very well when oriented vertically. When stood up near a vertically oriented cylinder covered in a metallic reflector material (i.e., inexpensive and durable, unlike a mirror), the geometry promotes lots of reflection and generation from both sides of a bifacial solar module.

Stationary Solar

Once stationary, a railcar is no longer constrained in all three dimensions. Solar generation area can be configured beyond the footprint of the railcar. Orientation to the sun is also fixed once stationary, so the tilt and direction of the solar energy generating system can be optimized and one or two-axis tracking can also be leveraged to maximize generation density.

Micro Wind

Innovations in the economics of micro wind generation have made possible a railcar-based system with sufficient capacity for Rail Energy purposes. Vortex Bladeless is a perfect example of just such an innovation. This bladeless wind turbine relies on an aerodynamic phenomenon called vorticity, in which wind flowing around a structure creates a pattern of small vortices or whirlwinds. Once the mini-whirlwinds become large enough, they can cause a structure to oscillate at a particular frequency, with the mechanical energy from these oscillations captured as electricity. Fundamental to Vortex Bladeless’ innovation is the ability to automatically very rigidity, allowing synchronization with the incoming wind speed and resulting oscillation frequency, enabling energy generation across a wide spectrum of wind speeds.  More importantly for Rail Energy, the downwind shadowing is much smaller than that of a bladed turbine, allowing a higher density.

Fuel Cell

In some scenarios, the energy density requirements are too great for the environmental conditions of a particular location. A fuel cell railcar can still meet the customer’s requirements. Bloomenergy manufacturers a solid oxide fuel cell system called The Energy Server that can be packaged onto a railcar and used to deliver Rail Energy in climates unsuited to sufficient solar and wind generation.