Develpment and Testing f the Neptunea Marine Hydrkinetic Energy Turbine A cllabrative prpsal between The University f Alaska Fairbanks Alaska Center fr Energy and Pwer & Real NewEnergy Cntact infrmatin: Partners: University f Alaska Fairbanks Jeremy L. Kasper Institute f Nrthern Engineering Alaska Center fr Energy and Pwer Alaska Hydrkinetic Energy Research Center PO Bx 755910 (fr shipping r FEDEX: 306 Tanana Lp, Duckering 525) University f Alaska Fairbanks, Alaska, 99775-5910 jlkasper@alaska.edu 907-474-5694 Real NewEnergy Jris D. Benninga Funding Partner 14601 Bnds Retreat Rad Acckeek, MD 20607 jris@realnewenergy.cm 301-283-0717 Ttal prject cst: $1,022,052 Grant funds requested: $747,896 Match funds cmmitted: $274,156 Previus prjects/applicatins: Nne Previus abstracts: Nne
Neptunea - The Alaska Center fr Energy and Pwer & Real NewEnergy Abstract: Neptunea Marine Hydrkinetic Energy Prject Descriptin Marine hydrkinetic (MHK) energy is a prmising energy resurce fr remte lcatins in Alaska if the technlgy can be deplyed reliably and affrdably. This prject will demnstrate that the technlgy is a well suited fr remte Alaska lcatins. The PAX Rtr is a bimimetic rtr that harnesses mre hydrkinetic energy in 40-60% shallwer waters than cnventinal hrizntal axis MHK rtrs adding excellent debris handling prperties, nn-fuling characteristics and nn-cavitatin prperties, all leading t higher capacity factrs, reduced maintenance and repair csts and increased up-time. The Alaska Center fr Energy and Pwer (ACEP) and Real NewEnergy (RNE) will use the PAX Rtr t develp and test a new methd f generating MHK energy. Cmbining the new rtr with an ingenius deplyment strategy marks a majr imprvement ver existing technlgy. A bttm-munted, cncrete cradle will supprt an ff-the-shelf hrizntal axis MHK turbine. The cradle allws fr slight turbine mvements, t align itself with the mtin f the PAX Rtr. The PAX Rtr will be cnnected t the turbine generatr via a flexible tethering cable. Due t the slight buyancy f the PAX Rtr and its shape, the Rtr establishes vertical and hrizntal equilibrium in the area f greatest flw, maximizing energy prductin. Additinally, the enhanced flexibility allws fr large, subsurface debris t glance ff the sides f the Rtr with smaller debris passing thrugh. The current Technlgy Readiness Level (TRL) is estimated t be 5 as the MHK turbine itself has been successfully deplyed in real perating cnditins and the PAX Rtr has been validated in a labratry (flume) envirnment; hwever, the cmbinatin and deplyment strategy is nvel. At the cmpletin f the prject, the team anticipates that the Neptunea system will prgress t TRL 7 r 8 and subsequent cmmercializatin will result in TRL 9 by year five. In rder t advance this technlgy, the team will imprve upn the existing designs f the PAX Rtr by cnducting extensive cmputatinal fluid dynamics (CFD) analysis. A full-scale, PAX Rtr will then be used with a prven Tcard 50kW permanent magnet direct drive generatr turbine. This system will be deplyed at the AHERC test site n the Tanana River in Nenana, AK (the TRTS) and mnitred using the specialized equipment available at the site. The team believes this deplyment scheme t be feasible since mst f the cmpnents are prven and/r simple in nature. Previus MHK deplyments in AK have been cut shrt by damage frm debris. The PAX Rtr has already demnstrated excellent debris handling prperties and in cmbinatin with added flexibility (tether) and avidance (bttm-munt), this system can succeed where ther MHK deplyment strategies have failed. Remte villages in Alaska culd in many cases benefit frm mid-scale (100-200 kw) MHK turbines. Rbust MHK slutins pse a variety f advantages ver traditinal and nn-traditinal frms f electricity generatin. Namely: N fuel csts, cmpared t rates in excess f $0.30/kWh fr diesel-based electricity in Alaskan villages Baselad electricity generatin reduces energy strage/management needs Can bring sizable quantities f pwer, capable f supprting Western lifestyle Prduces als in winter (under the ice), althugh flw speeds are less than in summer Adds t reliability f lcal energy system; MHK shuld prve t be mre reliable than diesel internal cmbustin engines which ften fail as a result f internal glazing Prject Innvatin The PAX Rtr is derived frm shapes and prperties existing in nature, bringing the efficiencies f natural flw t fluid-handling technlgy. Als knwn as bimimicry, this engineering practice adapts natural slutins t Page 2 f 5
Neptunea - The Alaska Center fr Energy and Pwer & Real NewEnergy human technical prblems. The shape f the PAX Rtr allws the turbine t cnvert energy frm a lnger stretch f water, leading t pwer increase, efficiency gains and the ability t perate in up t 60% shallwer water than cnventinal MHK rtrs. This is f interest t MHK develpers as many fast-flwing tidal and inriver sites are t shallw fr MHK deplyment. Neptunea will significantly increase the number f viable sites fr MHK develpment, allwing the industry t reach the ecnmies f scale necessary t reduce cst. PAX s 2008 testing revealed unique rtr characteristics which lead t increased availability f MHK turbines: The leading edge f the PAX Rtr recedes as it rtates, greatly reducing the damaging effects f debris. Small debris passes easily thrugh the turbine; larger bjects will glance ff the side f the blades The bimimetic rtr is nn-fuling, increasing efficiency and reducing maintenance Fr high flw sites, this rtr will greatly reduce the effect f cavitatin which is knwn t cause cyclic stress t prpellers, leading t surface fatigue and damage t the device The cncrete cradle will be heavy enugh t remain fixed t the bttm while still easily deplyable and salvageable via either a cmmn barge-munted crane r fltatin. The cradle als prtects the generatr frm ptentially harmful subsurface debris. The flexibility in the tether-rtr cnnectin reduces debris impacts t the PAX Rtr. In this way, direct strikes t the PAX Rtr shuld be rare and benign. The easily deplyable cncrete cradle and the expected resiliency t damaging debris impacts shuld lead t lwer capital csts, less perating expenditures and lnger lifetimes. Prject Site and Demnstratin Envirnment ACEP perates the AHERC test site n the Tanana River in Nenana, AK. AHERC is a fully permitted testing center that has specialized equipment and instruments alng with experienced researchers and engineers t cnduct detailed testing campaigns. AHERC has cmpleted a detailed characterizatin f river bathymetry, current flw, fish ppulatin, bed-lad and suspended sediment transprt, and riverbed cnditins at the TRTS. Summer flws at the test site are favrable, averaging 2 m/s. Hwever, these strng flws push large debris dwn the river, presenting a threat fr turbine destructin. Alaska has already seen three MHK prjects prematurely ended due t damage frm debris. Overcming this bstacle is a vital step if Alaska is t realize its vast MHK resurces 1. Icing in winter is anther prblem that has cnfunded MHK develpers, while energy security in the winter is a real pririty in rural villages. The flws are significantly less in the winter, but even a small amunt f energy prductin will help ffset diesel cnsumptin and prevent depletin f persnal r cmmunity supply. The bttm munted Neptunea will nt be remved during the winter and the mnitring campaign will cntinue. Pririty This prject fulfills all fur pririty cnsideratins. ACEP is the lead prject rganizatin and will effectively use its resurces acrss the campuses f the University f Alaska t develp and test this new slutin. ACEP is partnering with RNE, a renewable energy innvatin cmpany that is making available a 50kW hrizntal axis MHK turbine thrugh its partnership with leading turbine manufacturer, Tcard. Additinal matching funds will be prvided by RNE thrugh in-kind labr while ACEP will prvide a cash cntributin t the prject in the frm f days at the AHERC test site. Mst imprtantly, this slutin has the ptential fr widespread use in the state 1 Assessment and Mapping f the Riverine Hydrkinetic Resurce in the Cntinental United States. EPRI, Pal Alt, CA: 2012. 1026880 Page 3 f 5
Neptunea - The Alaska Center fr Energy and Pwer & Real NewEnergy thrugh in-river and tidal deplyments. Many cmmunities lcated n navigable waterways culd benefit greatly frm MHK energy generatin. Technlgy Validatin and Data Cllectin The perfrmance will be measured using the fllwing parameters: Electricity prductin (kwh) Pwer utput (kw) Debris handling (uptime, visual & snar) Fish mnitring (bservatin & snar) Winter utput (kwh in winter) Deplyment (cst and time) O&M ($ and time) A successful prject wuld be characterized by near-cnstant electricity prductin, full pwer utput (50kW) at peak flws and debris diversin cnfirmed by 100% uptime. Electric utput during the winter and cntinued survivability wuld als be viewed as a grund-breaking achievement. A time-lapse camera system will be used t mnitr surface debris and high-reslutin snar, a mechanical debris detectin device and direct bservatin will be used t detect subsurface debris. All equipment and labr necessary fr the testing campaign has been included in the budget which will be strictly mnitred t determine valuable indicatrs such as develpment, capital and perating expenditures (DEVEX/CAPEX/OPEX) and ttal cst f electricity including seasnal fluctuatins. Prject Schedule and Prject Budget Gantt Chart & Budget Mnths after Award 2 4 6 8 10 12 14 16 18 20 22 24 Prject Management $140,000 Testing develpment & prject preparatin Develpment f PAX Rtr design $25,000 $55,000 Final Neptunea design Implementatin $130,000 $325,000 Mnitring, analysis & reprting $240,000 Evaluatin The prject has been estimated t cst $1,022,052 including matching funds f $274,156 (27%). The Tcard turbine has been valued at $150,000 and match f $124,156 will be prvided by AHERC, in the frm f time at the TRTS and salary supprt fr researcher G. Re. G/n-g milestnes will ccur after (1) the PAX Rtr has been designed t ensure it is ready fr manufacture f a full-scale Rtr; (2) fllwing the final Neptunea design but befre prcurement f expensive cmpnents; and (3) prir t the winter freezing t determine whether the team feels cnfident t leave the Neptunea system deplyed indefinitely. Additinally, the prject schedule will be reevaluated thrughut the curse f the prject t determine whether the prject can be cmpleted in less than 24 mnths. Prject Team Qualificatins $110,000 Page 4 f 5