The following is a short list of projects Re Vision has been involved in over the past few years. This is by no means a comprehensive list, but is a representative subset of the type of projects in which we have been involved.

Re Vision Consulting, along with AWS Ocean, formed the Waveswing America team and drew upon over 40 years of work and research in this field to optimize a sub-sea pressure-differential point-absorber which utilizes efficient linear generator technology and advanced control algorithms to maximize energy yield, while reducing costs. Revision Consulting placed 3rd out of 97 teams that competed in the Wave Energy Prize competition hosted by the Department of Energy for their work on this project. You can read more about this project here.


Re Vision Consulting, in collaboration with Ocean Energy USA, Resolute Marine Energy, CalWave, Navigant Consulting, and University of Michigan, is developing an optimal control algorithm framework that can be applied to any WEC topology under development. The algorithm framework includes causal and non-causal controls methods. A deterministic wave prediction system is being developed in parallel to enable the non-causal MPC controls frameworks. Device performance improvements will be validated through wave-tank and in-ocean testing. This project will, demonstrate the impact of optimal controls on 3 different WEC topologies.

Publications:


The Ocean Energy (OE) Buoy, based on the oscillating water column principle, converts wave energy into useful mechanical energy using the principle that the air contained in the plenum chamber is pumped through an air turbine system by the wave action. This mechanical energy is then converted to electrical power. The device isolates the power conversion system from the seawater and also provides a high speed air flow to the turbine. The OE Buoy has been extensively tested at one quarter scale in real sea conditions for over 3 years resulting in a maturing of the technology to a Technology Readiness Level (TRL) 6. Now, Ocean Energy USA (www.oceanenergy.ie) is developing an optimized version of its oscillating water column technology through a techno-economic optimization process. Re Vision Consulting is assuming the technical lead-role in this project. The scope of work includes the following elements: (1) device performance modeling using in-house time-domain code, (2) extreme loads modeling using CFD, (3) structural design in steel, concrete and FRP, and (4) techno-economic optimization.

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Re Vision consulting is developing an optimal control system for Resolute Marine Energy’s (www.resolutemarine.com) Surge WEC device, leveraging it’s feed-forward controls algorithm framework. The 2-year project aims to substantially improve the SurgeWEC device performance and reduce the cost of energy produced by this technology. The SurgeWEC is a near-shore shallow-water hinged flap device. Initial application targets for the technology is providing power for desalination applications in niche markets.

Publications:

 

Ocean Energy (www.oceanenergy.ie) was awarded a contract to build and test a 400kW prototype at the Wave Energy Test Site (WETS) at the Marine Corps Base in Hawaii. Re Vision Consulting is assuming the technical lead-role in this project. As part of this project, an advanced instrumentation package developed by Re Vision will allow for the real-time prediction of ocean waves.

Publications: None yet

In order to site marine renewable projects, a wide range of stakeholders will need to understand the driving considerations for siting projects in certain areas. Marine renewable energy sources include: (1) wave energy, (2) offshore wind, (3) ocean current, and (4) ocean thermal energy conversion. These resources are estimated to be able to provide a significant portion of the US national demand for electricity and hence are strategically important.
Re Vision is developing an easy to use GIS-based scenario-modeling tool that allows users to characterize the commercial potential of a particular site or larger geographic areas. It will do so by utilizing the experience gained over the past decade in developing such scenarios for a wide range of clients.

Publications: None yet

Advanced wave prediction and concurrent online adjustment of the operating parameters (such as hydraulic system pressure and generator load) of existing wave energy conversion (WEC) devices has the potential to increase the power extracted from ocean waves by such devices by at least 200% over presently used approaches. However, commercial devices under development today still use control strategies based largely on 'slow-tuning' approaches, which result in significantly reduced wave power extraction and poor economic viability. This is largely due to two major issues: (1) the difficulty of predicting the waves encountered by a WEC system 20-40 seconds in advance, which is required to effectively implement optimal tuning strategies, and (2) the challenges associated with optimizing the control system, given various nonlinear system behaviors and constraints.

Re Vision is developing a toolbox under funding from the National Science Foundation (NSF) that will allow for the development of optimal control systems for different WEC device topologies.


Work at sea is extremely expensive; even for small inspection tasks, large vessels have to be mobilized to deploy manned intervention strategies. The cost of these operations contribute significantly to the cost of electricity from these offshore power plants, especially during the early phases of industry development. Unmanned and remotely operated vehicle technology has made significant progress over the past five years. With funding from the US Department of Energy, Re Vision Consulting is developing an autonomous vehicle platform that can be used to carry out a range of inspection and subsea intervention tasks - reducing intervention cost for some operations by an order of magnitude. It will address critical technical barriers related to the practical operation of these vehicles in the harsh offshore environment and enable a cost-reduction pathway that is a critical component of lowering the O&M cost of marine renewable energy installations.

In collaboration with Synapse Energy Economics and under contract to the Nova Scotia Utility Board, Re Vision is developing a Feed-In Tariff (FIT) structure for commercial tidal projects in the Bay of Fundy. The proposed FIT structure is expected to spur commercial development of tidal power in one of the world’s most significant tidal resources. The scope of work includes: (1) An independent assessment of project costs and device performance at the proposed deployment site, (2) Development of a proposed FIT structure that will spur commercial development, while minimizing rate-payer cost, and (3) Refinement of FIT through a stakeholder process consisting of device developers, utilities, consumer advocates and various other stakeholders.

In 2006, Re Vision Consulting (under contract to EPRI) has identified the Minas Passage in the Bay of Fundy as a major tidal energy resource in a tidal energy collaborative effort that included a wide range of stakeholders in the US and Canada. As a direct result of these efforts, FORCE was founded to develop a tidal energy site, which houses four grid-connected births.

Based on our recommendations, theNova Scotia Utility Board approved a “declining block” Developmental Tariff in November 2013. Feed-in rates were set at $455CAD/MWh for 1MW - 5MW scale projects and $375CAD/MWh for 5MW - 10MW projects. In December 2014, four developers were approved to build out 17.5 MW of tidal power under this scheme. The decision-support documents provide cost breakdowns for deployments at these scales, which were established through an industry consultation process. Details can be found here.


RE Vision was tasked to develop a performance and extreme loads assessment software tool for a novel WEC device and use it to perform system levels optimization for a commercial client. RE Vision developed the computational model using its in-house code and validated these models using a series of wave tank tests. A significant number of design variations were investigated to optimize the system. Over 100,000 dynamic model runs were carried out on a computational cluster with 256 cores. All the structural components and dimensions were parametrically defined to allow for a fully coupled optimization process that minimizes cost of electricity while maintaining appropriate factors of safety in the structural design. Leveraging Re Vision's techno-economic modeling capabilities, optimal design configurations were identified and refined.

Re Vision developed conceptual designs of a total of five different reference models in collaboration with US National labs. This included the following aspects: (1) mooring design, (2) structural design, (3) powertrain design, and (4) installation/operational design. Solidworks was used for the structural design, FEA, and concept visualization. Initial loads and performance assessments were carried out using rudimentary analysis.

Publications:

RE Vision was tasked to perform a cost and economic assessment of a wide range of reference model devices including: (1) a dual-rotor horizontal axis tidal device with variable pitch rotors, (2) a dual-rotor vertical axis river hydrokinetic device, (3) a heaving point-absorber working against a reaction plate, and (4) a quad-rotor ocean current device suitable for deployment in the gulf-stream. Additional devices are presently under development. The scope of work was aimed at fully quantifying the technology's cost and economic profile and included the following sub-tasks:
  1. Capital cost assessment of the technology (manufacturing, construction sub-system integration, transportation to staging site)
  2. Design of installation procedures and selection of appropriate equipment
  3. Installation cost
  4. Failure rate analysis of system
  5. Operational process development
  6. Operational lifecycle cost assessment
  7. Device performance assessment
  8. Economic analysis
The results of this work will provide insight into present-day costs and potential cost reduction pathways for a selected set of technology platforms.

Publications:
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The theoretical ocean wave energy resource potential exceeds 50% of the annual domestic energy demand of the United States, is located close to coastal population centers, and, although variable in nature, may be more consistent and predictable than some other renewable generation technologies. As a renewable electricity generation technology, ocean wave energy offers a low air pollutant option for diversifying the U.S. electricity generation portfolio. Furthermore, the output characteristics of these technologies may complement other renewable technologies.
 
This study addresses the following:
(1)   The theoretical, technical and practical potential for electricity generation from wave energy
(2)   The present lifecycle cost profile (Capex, Opex, and Cost of Electricity) of wave energy conversion technology at a reference site in Northern California at different plant scales
(3)   Cost of electricity variations as a function of deployment site, considering technical, geo-spatial and and electric grid constraints
(4)   Technology cost reduction pathways
(5)   Cost reduction targets at which the technology will see significant deployment within US markets, explored through a series of deployment scenarios
 
RE Vision Consulting, LLC (RE Vision), engaged in various analyses to establish current and future cost profiles for marine hydrokinetic (MHK) technologies, quantified the theoretical, technical and practical resource potential, performed electricity market assessments and developed deployment scenarios. RE Vision was supported in this effort by NREL analysts, who compiled resource information, performed analysis using the ReEDS[1] model to develop deployment scenarios, and developed a simplified assessment of the Alaska and Hawaii electricity markets.

Publications: Final report

To validate two theoretical performance models developed in the commercial AQWA code and RE Vision's in-house code, a series of wave tank tests were carried out at the UC Berkeley wave tank and the Scripps Institute of Oceanography wave tank. Tank testing scales to evaluate extreme survival loads were carried out at 1:50 and 1:100 scale and performance validation was carried out at 1:30 scale.

To establish a performance and cost baseline for a typical hydraulic powertrain in a wave energy conversion device, RE Vision was tasked to conceptualize a 100kW power module that could be used as a benchmark for WEC design efforts. The scope included a selection of off-the shelf components, cost assessment, quantification of losses in the powertrain, an assessment of maintenance cycles and an assessment of failure events.

RE Vision was tasked to develop a performance and extreme loads assessment software tool for a multi-point absorber WEC device. RE Vision developed the computational model using its in-house code and validated these models using a series of wave tank tests.

Publications: None – commercial project
The Marine and Hydrokinetic (MHK) Jobs and Economic Development Impact Model (JEDI) is designed to demonstrate the economic impacts associated with developing and operating MHK power systems in the United States. Hydrokinetic technologies include wave, tidal, river hydrokinetic, and ocean current technologies. The model was developed in collaboration with MRG Associates and NREL.
MHK is an emerging renewable technology sector with limited deployed capacity (about 5 MW) to date. Unlike wind and other renewable and conventional technologies, there are relatively few examples of commercial applications operating today and little publicly available cost data [installation or operation and maintenance (O&M)] for these systems. In the absence of historical cost data, engineering cost models were used to develop a set of reference cost data.

Publications:
To accelerate the adoption of these emerging marine hydrokinetic technologies, navigational and environmental issues and concerns must be identified and addressed. As hydrokinetic projects move forward, various stakeholders will need to be engaged; one of the key issues that project proponents face as they engage stakeholders is that many conflicting uses and environmental issues are not well-understood. Much of this lack of understanding comes from a limited understanding of the technologies themselves.
To address this issue, RE Vision Consulting, applied a scenario-based assessment approach to the emerging hydrokinetic technology sector. The goal was to improve understanding of potential environmental and navigation impacts of these technologies and focus stakeholders on the critical issues.

Publications:
PG&E was establishing a wave energy test site in California. RE Vision Consulting acted as a consultant on the project and supported all siting and permitting activities of the project team, including; (1) resource assessments, (2) technical feasibility studies, (3) subsea cabling studies, (4) technology screening activities, and (5) cost and economic assessments. Unfortunately, PG&E made a decision to discontinue wave-energy related efforts in 2010.

Publications: None – commercial project

A one-day and two-day course was developed to educate Mineral Management Service (now BOEMRE) and FERC staff members about marine renewable technologies. The class was well received at both agencies and was recorded for continued use.

Publications: None

A study was carried out for the California Energy Commission to: (1) assess the wave energy resource potential, (2) identify candidate technologies and operational issues, (3) establish cost profiles from this emerging technology, (4) identify environmental issues and (5) identify permitting processes as they relate to the State of California.

Publications:
  • Previsic, Mirko. 2006. California Ocean Wave Energy Assessment. California Energy Commission, PIER Renewable Energy Technologies Program Area. CEC-500-2006-119 California Ocean Wave Energy Assessment

The Electric Power Research Institute (EPRI), under the sponsorship of the Alaska Energy Authority (AEA), Anchorage Municipal and Light, Chugach Electric and the Village of Iguigig, conducted a study to investigate the feasibility of a technology known as River In-Stream Energy Conversion (RISEC) for Alaska river applications. RISEC technology converts the kinetic energy of water in free-flowing rivers into electricity by placing water turbines (similar to wind turbines) directly into the flowing water.
A total of six river sites were selected for site assessment. After careful review, three sites were selected for conceptual level feasibility studies, the results of which are described in this report. The three sites were:
  • Tanana River at Whitestone
  • Yukon River at Eagle
  • Kvichak River at Igiugig
RE Vision performed all technical work on this project, including: (1) site assessment, (2) system-level design, (3) performance, and (4) cost and economic assessment.

Publications
The Electric Power Research Institute (EPRI), with funding from seven different states and provinces in the US and Canada (Maine, Massachusetts, New Brunswick, Nova Scotia, Alaska, Washington, and California) conducted a collaborative study to investigate the feasibility of tidal energy technology. RE Vision Consulting, in collaboration with UW, performed all the technical feasibility studies, cost, performance and economic assessments and produced a number of reports.

Publications
The Electric Power Research Institute (EPRI), with funding from five different coastal States (California, Hawaii, Maine, Massachusetts, Oregon) conducted a collaborative study to investigate the feasibility of wave energy technology within these US-based locations. RE Vision Consulting performed all the technical feasibility studies, cost, performance and economic assessments and produced a number of reports.

Publications