Hydrowires: Advancing Hydropower Flexibility through Modular Upgrades

Case Study: Hydrowires – Advancing Hydropower Flexibility through Modular Upgrades

Client: U.S. Department of Energy (DOE) – Water Power Technologies Office (WPTO), Office of Energy Efficiency and Renewable Energy (EERE)
Prime: Littoral Power Systems, Inc. (LPS)
Partners:

  • Electric Power Research Institute (EPRI) – Modeling Tools & Advisory
  • Norm Bishop Consulting LLC – Hydraulic Structures & Grid Services
  • McCullough Consulting LLC – Structural Engineering
  • Hydro Performance Processes Inc. – Turbine Fatigue & Dynamics
  • Asilea Energy – Market Assessment
  • HydroDyne Energy and Olcott Harbor LLC – Site Hosts and Field Input

Timeline: September 1, 2023 – April 30, 2024 (9-month discovery phase)

Project Summary

LPS developed and assessed the h-Dynamyk™ Flexibility Upgrade Kit under DOE award DE-EE0010188, in response to the growing need for flexible hydropower solutions that can complement variable renewable energy sources like wind and solar. This nine-month feasibility study addressed how aging hydropower plants can be upgraded to deliver fast ramping, ancillary services, and efficient operation under constrained flows, with minimal civil modification.

The Challenge

Traditional hydropower plants were designed for baseload operation and often suffer from inefficiencies, mechanical fatigue, and limited operational flexibility under today’s dynamic grid conditions. Retrofitting such systems to meet modern grid demands—such as frequency response, black-start capability, and spinning reserve—typically involves costly civil works and extended downtimes. LPS set out to overcome these constraints by engineering a modular retrofit system that can rapidly integrate into existing facilities with minimal disruption.

LPS’s Role

LPS served as the prime recipient and technical lead for the Hydrowires project. LPS was responsible for the end-to-end design, engineering, modeling, and integration of the h-Dynamyk™ Flexibility Upgrade Kit. This included:

  • System Architecture Development: Designing the baseline siphon turbine, power electronics, and smart control modules tailored for rapid retrofit of legacy hydropower plants.

  • Engineering Design and Fabrication Standards: Implementing robust mechanical and structural designs using USACE and AISC standards for reliability and manufacturability, while optimizing for modularity and rapid deployment.

  • Simulation and Analysis: Leading the use of the EPRI High-Flexibility Framework (HFF) tool to model baseline and upgraded plant performance, including dispatch scenarios, fatigue analysis, and revenue modeling.

  • Controls Integration: Adapting LPS’s existing k-IOT™ supervisory platform into a smart control system capable of optimizing dispatch under dynamic grid and hydrological conditions.

  • Industry Engagement: Coordinating with advisory board members and technical experts to ensure system alignment with utility-scale requirements, market needs, and deployment constraints.

  • Commercialization Planning: Collaborating with partners to assess market applicability, identify target hydropower sites, and establish a commercialization pathway for the upgrade kit.

Through this leadership role, LPS demonstrated its core engineering capabilities in hybrid systems design, grid-responsive hydropower controls, and modular infrastructure.

Engineering Highlights / Technical Solution

The h-Dynamyk system was conceived as a modular, flexible retrofit package designed to enhance the operational range and responsiveness of existing hydropower facilities. The system includes three primary components:

  1. Siphon Turbine Assemblies: Outfitted with LPS’s Reakt® propeller turbine and designed to operate at low flows when legacy units are offline or inefficient. The siphon modules drop over spillways and are supported by integrated priming systems. Each turbine is rated at 300–500 kW, with combined capacity up to ~1 MW.

  2. Power Electronics: Medium-voltage (4160 V) Variable Frequency Drives (VFDs) enable variable-speed operation of turbines, allowing for improved efficiency across a range of flows. This decouples turbine speed from synchronous grid requirements, enabling smoother operation during ramping and partial load conditions.

  3. Smart Supervisory Controls: LPS’s proprietary k-IOT™ platform integrates edge computing and cloud analytics for remote monitoring, real-time dispatch optimization, and fault diagnostics. The controls system was enhanced to simulate multi-variable operating scenarios that incorporate economic, environmental, and hydrological data.

Design Features:

  • Modular subassemblies for rapid deployment (2–4 weeks installation)

  • Lightweight, corrosion-resistant materials (CA6NM, ASTM A500 steel)

  • Fabrication standards based on USACE ETL 1110-2-584 for hydraulic structures

  • Forklift and crane-compatible components for ease of handling

  • Plug-and-play electrical and control skids using standard NEMA enclosures

Simulation Framework and Approach

To evaluate the h-Dynamyk system’s impact, LPS selected the Reusens Hydroelectric Project (10 MW, 4-unit Francis turbine plant) as the representative modeling site. This facility operates under PJM Interconnection and typifies many U.S. legacy hydropower stations.

LPS used the EPRI High-Flexibility Framework (HFF) Tool—validated under DOE’s HydroWIRES initiative—to simulate both baseline and upgraded plant operations. Two scenarios were modeled:

  • Baseline: Fixed-speed legacy turbines with no flexibility features

  • Upgraded: Full integration of siphon turbine, VFDs, and smart controls

Input Parameters included:

  • Reservoir inflow (10,000 to 130,000 cfs-hrs.)

  • Real-time pricing from PJM (e.g., July 9 and July 30, 2023)

  • Legacy turbine efficiency curves

  • Dynamic dispatch signals and minimum flow conditions

The siphon turbine was modeled as a “minimum flow” unit capturing otherwise wasted water. Upgraded units were simulated with improved efficiency curves and ramping capabilities. The smart controls enabled dynamic plant dispatch based on system constraints and market signals.

This plant-wide, physics-consistent model captured interactive effects among turbines, electronics, and controls, allowing a full-system evaluation of energy output, fatigue reduction, revenue improvement, and load-following behavior.

Results & Outcomes

The plant simulation analysis revealed that h-Dynamyk significantly improved operational performance under both constrained and dynamic flow conditions:

Energy Generation

  • Up to 219% generation increase under very low flows (10,000 cfs-hrs.)

  • 12.6% increase in generation at moderate flows (40,000 cfs-hrs.)

  • 20–30% AEP gains were observed across common flow regimes

These gains were enabled by:

  • Improved part-load efficiency

  • Siphon turbine utilization during minimum flows

  • Optimized dispatch through smart controls

Revenue Enhancement

  • 26–37% revenue uplift due to better alignment with energy market pricing and extended operation under previously non-generating conditions

  • Revenue gains did not account for ancillary services, suggesting additional upside potential from frequency response, spinning reserve, and black-start services

Grid Flexibility

  • <10-second ramp time to full load, allowing rapid participation in fast-response markets

  • Improved performance during frequency regulation and dispatch ramping scenarios

Fatigue Reduction

  • Operation near best-efficiency point reduced exposure to damaging load zones (start-stop, low-load, speed-no-load)

  • Potential for up to 50% reduction in fatigue-induced lifecycle cost impacts

  • Estimated extension of turbine service life from 7.5 years (under flexible operation) to 30 years (under optimized operation)

Cost and Installations

  • $0.045/kWh target LCOE achieved, comparable to leading storage and renewable technologies

  • Pre-engineered modular design supports installation in under 4 weeks

  • Reduced downtime and avoided heavy civil modifications minimize disruption and total capital cost

Site Suitability and Market Potential

  • Market assessment identified 435 U.S. sites as viable for full deployment

  • An additional 618 sites could benefit from control and electronics upgrades alone

  • Ideal for aging plants under relicensing, constrained flow regimes, and utilities seeking dispatchable capacity with low installation risk

Impact

The Hydrowires project demonstrated that LPS’s h-Dynamyk™ Flexibility Upgrade Kit can play a critical role in modernizing the aging U.S. hydropower fleet. By combining modular siphon turbines, power electronics, and smart controls, the system provides a scalable pathway to:

  • Enable flexible operation in response to dynamic grid demands.

  • Increase energy yield under constrained and off-design flow conditions.

  • Unlock new revenue through participation in ancillary services markets.

  • Reduce mechanical fatigue and extend the lifespan of legacy infrastructure.

  • Lower LCOE through minimized civil work, rapid installation, and improved efficiency.

With over 1,000 potential U.S. hydropower sites identified for partial or full system deployment, the project establishes a compelling technical and economic case for integrating modular upgrades into existing facilities. The work aligns directly with national objectives for grid resilience, decarbonization, and sustainable infrastructure investment.

Next Steps / Future Work

LPS is now advancing the h-Dynamyk™ system toward field deployment by:

  • Initiating prototype development and planning for a pilot-scale demonstration.

  • Engaging with hydropower site owners for feasibility assessments and early adoption.

  • Refining smart controls integration and installation workflows.

  • Exploring commercial partnerships and funding opportunities for scaled rollout.

These efforts aim to transition the system from validated concept to real-world application.