1. Emerging Technologies In Ocean Kinetic & Enhanced Geothermal
Energy Days 2012: Many Paths for Sustainable Energy
Michael Robinson, PhD
NREL’s National Wind Technology Center
February 23, 2012
NREL is a national laboratory of the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy operated by the Alliance for Sustainable Energy, LLC

2. DOE Technology Readiness Level (TRL)
Technology Status
TRL 1 - Basic Research
TRL 2 - Applied Research
TRL 3 - Critical Function or Proof of Concept Established
TRL 4 - Laboratory
Testing/Validation of Alpha Prototype Component/Process
TRL 5 - Laboratory
Testing of Integrated/Semi-Integrated System
TRL 6 Prototype System Verified
TRL 7 - Integrated Pilot System Demonstrated
TRL 8 - System Incorporated in Commercial Design
TRL 9 - System Proven and Ready for Full Commercial Deployment
National Renewable Energy Laboratory Innovation for Our Energy Future

3. Geothermal & Ocean Hydro-Kinetic Resource Potential
Emerging Renewable Technology
World Resource Estimate (TWh/Year)
US Resource Estimate (TWh/Year)
Enhanced Geothermal
---
778,000,000 (8)**
Wave Energy
29,500 (1)
2,640 (3)
Tidal Current Energy
7,800 (1)
525 (4)
River Current Energy
 ---
110 (6)
Ocean Current Energy
43,800 (7)
5 (5)*
Electricity Demand by 2030
12,000 (1)
4,586 (2)
--- No Published Estimate Available
* Extractable Estimate %
** Extractable Estimate 20%
(1) An International Vision for Ocean Energy IEA OES October 2011
(2) EIA Annual Energy Outlook 2012
(3) Mapping & Assessment of the US Ocean Wave Energy Resource, EPRI 2011
(4) DOE Mapping Assessment Project, 2011
(5) DOE 1980 Estimate; DOE Update assessment in Progress
(6) NYU 1986; DOE Update Assessment in Progress
(7) Ocean Current Energy Potential on the U.S. Outer Continental Shelf, MMS 2006
(8) Impact of Enhanced Geothermal Systems (EGS) on the United States in the 21st Century, MIT 2006
National Renewable Energy Laboratory Innovation for Our Energy Future

4. Enhanced Geothermal Systems (EGS)
Enhanced Geothermal Innovation
Conventional geothermal limited by the number of naturally occurring reservoirs near the surface
Heat, Permeable Rock, Water
EGS technology creates a permeable energy reservoir by hydroshearing rock along existing fractures and using pumped fluid for energy extraction
Energy Extraction Potential Function of Reservoir Size, Temperature & Fracture Surface Area
Energy delivery potential four orders of magnitude greater than total domestic energy demand
Innovations Required Through R&D
Drilling technology – enabling access to deeper, hotter regions in high grade formations
Power conversion technology – improving heat transfer performance leading to an order of magnitude improvement in reservoir performance and power conversion efficiency
Reservoir technology – increasing production flow rates and heat removal efficiencies in fractured rock
Technology Maturity
RD&D Stage – TRL Level 2-3 for subsurface technology development
Technical barriers & obstacles can be overcome with R&D investment
40 GW wind US; 240 GW worldwide
3 GW geothermal; 11 GW worldwide
National Renewable Energy Laboratory Innovation for Our Energy Future

5. National Renewable Energy Laboratory Innovation for Our Energy Future
Ocean Wave Technologies
Technology Development Approaches
Overtopping Technology – both wave height and surge, wave energy collected into a central basin and released though a low head hydro turbine
Point Absorber – Buoy motion relative to a floating or fixed bottom reference drives a hydraulic or electric actuator producing energy
Oscillating Water Column – Wave motion increases & decreased water level in a contained reservoir thereby driving air through a conventional air turbine producing electricity
Wave Surge – Drag collector moves with the wave surge driving a hydraulic actuator that can be collected and/or direct coupled to an electric generator
Floating Attenuator – Sectioned floating structure linked by hydraulics; wave motion drives hinged
Wave Dragon - Overtopping
OPT Point Absorber
Oceanlinx Oscillating Water Column
motion between sections that can pressurize a hydraulic reservoir and/or is direct coupled to an electric generator
Pelamis Floating Attenuator
Oyster Wave Surge Technology
National Renewable Energy Laboratory Innovation for Our Energy Future

6. National Renewable Energy Laboratory Innovation for Our Energy Future
Tidal & Current Turbine Technologies
Technology Development Approaches
Oscillating Hydrofoil – Current flow over the airfoil creates lift driving the attached piston which in turn drives a generator or hydraulic accumulator. At the end of the stroke, the blade pitches creating lift in the alternate direction to complete a cycle.
Horizontal Axis Turbine – Flow through the rotor, ocean current or river, drives an electric generator to produce electrical power; derived from HAWT wind turbine technology utilizing many of the same design tools.
Vertical Axis Turbine – Flow through the rotor, ocean current or river, drives an electric generator to produce electrical power; derived from VAWT wind turbine technology. Mounted parallel to the water utilize the highest flow rate.
OPT Point Absorber
Engineering Business Limited
”Stingray”
SMD Hydrovision
Verdant Power
Free Flow Power
Oyster Wave Surge Technology
Marine Current Turbines
Ltd.
Ocean Renewable Power Company
Verdant Power
National Renewable Energy Laboratory Innovation for Our Energy Future

7. National Renewable Energy Laboratory Innovation for Our Energy Future
Barriers to Marine & Hydrokinetic Commercialization
Technology in the early stages of development and demonstration
Wide variety of technology options – over 40 different development efforts in the US & many more internationally
No clear “winners or losers” to focus resources on design optimization & development
Significant maturation ranges with TRL’s from 1 to 6
Device functionality and associated risk require validation
Modeling & analysis tools in their infancy
Cost & performance data derived from commercial and pre-commercial prototype demonstration projects do not exist
Initial technology design costs as high as 70 – 100 ¢/kWh, an order of magnitude too high to be competitive with existing generation
Significant capital investment required to pass through the four technology development stages:
1) Controlled tank & tow test at scale,
2) Scaled prototype test & verification,
3) Full scale pre-commercial prototype test & validation,
4) Small demonstration projects of multiple units
Environmental & Permitting
Lack of data on environmental risks hamper early demonstration & deployment
Uncertainty in achieving permitting and high cost of meeting EA process
National Renewable Energy Laboratory Innovation for Our Energy Future

8. National Renewable Energy Laboratory Innovation for Our Energy Future
Marine & Hydrokinetic Future Prospects
Many of the current barriers to deployment are identical to the early days of land based wind technology development.
Development of international standards for the design, development & deployment of MHK are in process through the IEC (TC 114)
Federally sponsored test facilities in the UK have reached 100% capacity (EMEC) and have transitioned to full commercial operation
Various international federal programs are providing incentives for early commercial development and demonstration
Significant investment in test facilities
South Korea is also heavily investing with 2 Tidal Power Stations built and a third underway
EU Goal for Ocean Energy is 3.6 GW of generating capacity by 2020 and to reach 188 GW of installed capacity by 2050
Investments by DOE are quantifying the US domestic wave, tidal and ocean current resources for development
Advanced tools, models, and materials to maximize efficiency and ensure survivability are under development at the National Laboratories
MHK reference model effort will develop benchmark cost and performance for various technologies and assess technology cost reduction pathways
Identification of critical cost drivers will inform DOE strategy for developing up to 15% of domestic electricity generation from wave, tidal and river resources by 2030
FERC issued a pilot commercial license to Verdant Power’s 30 MW RITE Project
Goal: Reduce COE to $0.06/kWh by 2030
National Renewable Energy Laboratory Innovation for Our Energy Future

9. National Renewable Energy Laboratory Innovation for Our Energy Future
Summary
Enhanced Geothermal Systems
Significant Resource Potential – Four Orders of Magnitude Greater Than TOTAL Domestic Energy Demand.
TRL Level 2-3; Primarily Subsurface Technology Development Required
LCOE Prediction is Premature; Expected to be at least Consistent With and/or Lower Than Conventional Geothermal Technology
Marine Hydro-Kinetic Technology
Supplying a Significant Percentage of the World’s Total Electricity Demand is Possible
TRL Levels Vary from 1-6; Wide Variety of Technology Options Being Developed
Early LCOE Estimates at Pre-Prototype Level range from 70 – 100 ¢/kWh
Significant Room for Innovation and Associated Cost Reduction Through Learning Curve Effects
Field Deployment & Validation Critically Needed to Validate Technology Pathways
Development Trajectory Consistent with the Performance Enhancements & Cost Reductions Experienced by the Wind Industry
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10. Questions? Mike Robinson, PhD Senior Technology Advisor
US Department of Energy
Wind & Water Program
Contact Information:
Phone:
NREL is a national laboratory of the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy operated by the Alliance for Sustainable Energy, LLC