Electricity Generation and Delivery

Columbia University's Electrochemical Energy Center will develop a long-duration grid energy storage solution that leverages a new approach to the zinc bromine battery, a popular chemistry for flow batteries. Taking advantage of the way zinc and bromine behave in the cell, the battery will eliminate the need for a separator to keep the reactants apart when charged, as well as allow all the electrolyte to be stored in a single tank, instead of multiple cells. This reduction in “balance of plant” hardware will reduce system cost.

The bottom, sides, and surface of rivers and tidal channels confine water flow, which significantly alters the operation of river and tidal turbines. As turbines harness the momentum of the moving water, they alter the flow around them—water passing through the blades of the turbine is slowed while water passing around the blades speeds up. When the area that a turbine array presents to the flow is an appreciable fraction of the channel cross-sectional area, changes to the flow increase array power output and efficiency.

Advanced Conductor Technologies will develop two-pole, high-temperature, superconducting DC power cables and connectors with a power rating of up to 50 MW to enable twin-aisle aircraft with distributed electric propulsion to reduce carbon emissions. The cables and connectors will contain insulation independent of the cryogenic medium used as coolant and allow an operating voltage of 10 kV. Because they have intrinsic fault current limiting capabilities, the cables can protect the power distribution network from over-currents.

To advance in-current marine and riverine hydrokinetic energy conversion through a step change in levelized cost of energy, Littoral Power Systems, Inc., and its partners propose to design, fabricate, and test a novel in-current hydrokinetic energy turbine device that imposes no net torque on the mooring. It is a submersed buoyant vehicle on a single flexible tether that flies a turbine up in the water column.

The project team, led by the University of Michigan, proposes the RAFT concept as a solution for hydrokinetic energy harvesting. The project aims to develop multi-physics models, design processes, and optimization tools; augment control and system health monitoring algorithms; demonstrate novel RAFT concepts; and deliver an integrated solution for riverine and tidal applications. The project team brings expertise in hydrodynamics, structures, electrical systems, iterative optimization, and control co-design.

The Tidal Power Tug is a tidal hydrokinetic turbine using a vertical yawing spar buoy with a horizontal-axis, parallel-flow rotor. The turbine will achieve stable, safe operation in all sea conditions with unprecedented cost performance gained by use of novel materials, vertical mass-buoyancy distribution, high power-to-weight ratio, efficient deployment/retrieval, adaptive controls for blade pitch and shear compensation, and advanced analytical tools for efficient operations and maintenance. These factors will result in high turbine up-time.

The University of Alaska Fairbanks' BladeRunner concept is expected to reduce operating expenses by 50% while significantly reducing infrastructure and personnel requirements on site. These improvements result in an LCOE of $0.0755 $/kWh. BladeRunner employs a floating generator housing and tethered turbine to create a HKT system that has low capital and operating costs and is well suited for community co-design. The turbine is coupled to the generator by a flexible torsion-cable that transmits mechanical power while allowing the turbine to deflect around debris.

The University of Virginia proposes a simple, resilient, and scalable solution, inspired by unsteady lift-based hydrodynamics observed in fish swimming. By adapting the concept of biological unsteady lift, the University of Virginia’s BIRE system aims to generate energy from the river environment through real-time control of pairs of out-of-phase oscillating hydrofoils placed into oncoming flow. The river flow causes the two foils to oscillate in opposite directions.

Many lower-cost fusion concepts require high-performance, long-life electrodes for plasma generation, sustainment, and refueling. Due to the plasma and high-current-density environments needed for fusion, electrodes can erode quickly, which contaminates and cools the plasma, leading to increased maintenance costs.

Rare earth barium copper oxide (REBCO) tapes enable >20-T (Tesla) magnets in compact, high-field magnetic-fusion devices. Commercial REBCO tapes are expensive at $300/kA-m (kiloampere-meter) based on the operating condition of HTS (high-temperature superconducting) magnets for compact fusion energy systems. The tape cost must be reduced to approximately $10/kA-m for HTS-based fusion systems to be commercially cost-competitive.