Post on 15-Dec-2015
Wyandotte Geothermal Utility
Pamela Tierney, Energy Services Program Manager
Overview of Wyandotte Municipal Services
Provides Water, Electric, Cable, Internet & VOIPWater Utility
Formed in 1889; Approx 10,000 customers; $4 Million Annual Revenue
Electric Utility Formed in 1892; Approx 12,000 customers; $44 Million Annual Revenue
Cable Utility Formed in 1981; Approx 8,500 customers; $10 Annual Revenue
Why Geothermal? Why Wyandotte?Overview / Market Status
Just Get Started / Barriers to AdoptionOptions for Overcoming Barriers
Pieces of the ProcessLessons Learned
Project Management
Why Did WMS Start a Geo-Utility? Is a dispatchable renewable energy sourceImproves system load factor – base
load/peaksEnergy Efficiency / Lowers customer’s
energy costsEconomic development
Improves System Load Factor
Helping Lower Customer’s Energy CostsCurrent Incentives in Wyandotte
30% Federal Tax Credit$1,000/ton Rebate from WMS1.99% APR Unsecured Loans Available
Other Programs OfferedHome Energy Audits – Encourage Overall Home
Performance; Insulation, Air Sealing, EE EquipmentSuite of Other Rebates & Incentives
Lowers Customer’s Energy CostsInputs - Wyandotte Home - Geothermal vs. Conventional
Calculation for Tons = 2Conventional - Annual Costs Geothermal Utility - Annual Costs
Year Elec Nat Gas MaintTotal Ops
Cost Elec GU Cust Chrg MaintTotal Ops
Cost Ann Save Cum Save
1 $521 $1,030 $210 $1,761 $679 $282 $54 $53 $1,067 $694 $6942 $542 $1,071 $218 $1,832 $706 $288 $54 $55 $1,102 $729 $1,4233 $564 $1,114 $227 $1,905 $734 $293 $54 $57 $1,138 $767 $2,1904 $586 $1,159 $236 $1,981 $764 $299 $54 $59 $1,176 $805 $2,9955 $610 $1,205 $246 $2,060 $794 $305 $54 $61 $1,215 $846 $3,8416 $634 $1,253 $255 $2,143 $826 $311 $54 $64 $1,255 $888 $4,7287 $659 $1,303 $266 $2,228 $859 $318 $54 $66 $1,297 $932 $5,6608 $686 $1,356 $276 $2,318 $893 $324 $54 $69 $1,340 $977 $6,6379 $713 $1,410 $287 $2,410 $929 $330 $54 $72 $1,385 $1,025 $7,662
10 $742 $1,466 $299 $2,507 $966 $337 $54 $75 $1,432 $1,075 $8,73711 $771 $1,525 $311 $2,607 $1,005 $344 $54 $78 $1,480 $1,127 $9,86412 $802 $1,586 $323 $2,711 $1,045 $351 $54 $81 $1,530 $1,181 $11,04513 $834 $1,649 $336 $2,820 $1,087 $358 $54 $84 $1,582 $1,237 $12,28214 $868 $1,715 $350 $2,932 $1,130 $365 $54 $87 $1,636 $1,296 $13,57815 $902 $1,784 $364 $3,050 $1,175 $372 $54 $91 $1,692 $1,357 $14,935
Lowers Customer’s Energy CostsGas Service Fee
$ 15.00
Gas Rate $ 1.06 CCF/Ton 0.12
Electric Rate $
0.13309 per Kwh Geo Htg COP 4
Customer Charge $ 4.50
Geothermal monthly rate $
11.75 per ton
Annual hrs heating 2600 Cost $25,400
Annual hrs cooling 1450 Simple payback 21 yearsInflation, elec, gas, maint 4.00% Rebates -$2,000
Inflation GU 2.00% 30% tax credit -$8,465.82
Hot water add for gas 0.35 Reduced cost$14,934.1
8
Conv A/C kW/Ton 1.35Adjusted payback 14.5 years
Geo AC kW/Ton 0.75
Possible Rebates and tax credits that may be available in Wyandotte
Economic DevelopmentHVAC Contractors / On-going Contractor SupportDrilling contractorsPipe ManufacturersEquipment Distributors/ManufacturersParts & Maintenance SuppliersCrane Operators – Commercial InstallationsWMS/City staffPurchases made locally in Wyandotte – lunch, supplies, etc.
Market & StatusMany GSHP manufacturersIGSHPA CertificationConventional HVAC vs. Geothermal debateEngineering the projectQuality drillersMaking the economics work
WMS Wanted to Remove BarriersSpace Constraints In Urban AreasLow Market Awareness Among Consumers / No sizzleThe Need for Ground Loop Adds Cost, Complexity & RiskCodes for Proper Design/Installation of Ground LoopRequires Installation Specific Design/Load calculations &
EngineeringGround Loop Repair & Maintenance Challenges
How the Geo-Utility was StructuredWyandotte Geo-Utility provides the ground loop
300 ft. vertical bores; one per home on averageGround loop located in public right of waysWMS assumes all ground loop risksFull shut off capacityCity passed GSHP OrdinanceRates based on capacity (tonnage) of systems installedCustomer responsible for internal system /connection
Rate Structure & Customer OptionsResidential Rate
Wyandotte drills & owns bore field$26.75 per ton + $4.50 monthly customer charge
Maintenance RateProperty owner buys down the rate by paying the
well costs; wells located in public right of way$11.75 per ton + $4.50 monthly customer charge
Property owner installs loop field on their propertyNo involvement by WMS; no costs paid to WMS
Revenue Generation Potential Bore field (Well) installation permit fee
$200 for first well$25 for each additional
Potential Tax Revenue with Public OwnershipCapitalized system; depreciation taken30 year average payback on bore field infrastructureGeothermal Electric Rates – under reviewRenewable Energy Credits (RECs) potential
Pieces of the Project/Process to Become a Customer
Customer - Internal Design, GSHP & Horizontal ConnectionDecides which rate option works for themSigns a Service AgreementObtains system quotes and hires a contractor to install GSHP and
horizontal connection – IGSHPA certified recommendedWMS – Bore field including engineering/design
Locate well on plot planContract driller
Driller will get permit from City and call Miss DIGComplete bore field and install service valves
City – inspects internal and external systems
What Wyandotte Installations Look Like
Drilling ExperienceUrban Area
Average lot width varies 40 ft. to 70 ft.Landscaped yards
Trees, sidewalks, driveways, curbs, porches, etc.Artesian Wells
Rotten egg odors/sulphurFractured Limestone
Consumes water and grout
Drilling Experience – Not Always Pretty
Drilling Experience – Not Always Pretty
Current Status56 installations already in the planning/design
stage or completed25 new residential installations 20 retrofit residential installations4 commercial installations2 new multi-family developments (20 units)4 Private home owners subscribed; 1 off grid
50 bore fields installed; 41 individual systems; 109 ton total capacity
31 Installations Complete & In Service
Lessons LearnedNew process – customers very dependent on our knowledge
and help Continuous education process / overcoming misinformation Avoid strip heaters where possible Re-teaching old habits – set back temperatures, filters
Cost analysis important – did they have A/C? Fuel type? Rate structure – what is too high?
Championing total home performance prior to installing Geothermal or other renewable – insulation, air sealing, etc.
Necessity of shut off ability
Lessons LearnedProject Management important – try and cover unforeseen
events – extra costs for grout, running water, odor, water sources, sewer/runoff provisions, safety, customer expectations…
Big difference in GSHP contractors Does the HVAC contractor understand Geo units? Single vs. 2
stage units? Floor drains/condensate pumps? Fresh air intake into return air/motorized dampers? Air balancing/duct size
Lessons LearnedBig difference in bore field drillers
Drillers competent to different depths Valve boxes - Compression fitting vs. poly fused valvesCost overruns on grout/drilling if fractures are hitType of groutGlycol %Pressure testing – leaving valve boxes exposed; coordinating
efforts with GSHP contractorPinched pipes or damage to well or compression fittings on valves
Lessons LearnedTrenching vs. directional bore; piping thru the side wall of
structure vs. under the footing New construction –
Coordinate drilling once construction nears completion; GC lays horizontal piping
GSHP should be installed in a clean area;Existing homes – directional boring; careful under footing;
piping diagrams often incomplete or depth incorrect for sewer lines, etc.
Q&A?
Thank you
Pamela Tierneyptierney@wyan.org