GEOTHERMAL HEAT PUMPS: CONCEPT TO COMPLETION Review of New England Regulations For The Installation And Operation Of Geothermal Heat Pump Wells Instructors:

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  • Slide 1
  • GEOTHERMAL HEAT PUMPS: CONCEPT TO COMPLETION Review of New England Regulations For The Installation And Operation Of Geothermal Heat Pump Wells Instructors: Paul Blain Joe Cerutti MassDEP Drinking Water Program
  • Slide 2
  • The Thermodynamics of It All Do GSHPs Work in Cold Climates? Coefficient of Performance (COP) = Heat Energy Output Electric Energy Input Industry claims COP ranging from 3 to 6 From the Carnot cycle: COP theoretical limit = Indoor Temperature (Indoor Temperature - Temperature of heat source/sink) MassDEP
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  • Thermodynamics (continued) Example: Heat a dwelling to 70 F ~ 294 K Ambient groundwater temperature in Massachusetts is typically about 54 F ~ 285 K From the Carnot cycle: COP theoretical limit = 294 K = 33 294 K 285 K MassDEP
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  • Thermodynamics (continued) What happens to the theoretical efficiency toward the end of the heating season if the entering water temperature has dropped to 35 F? 35 F ~ 275 K COP theoretical limit = 294 K = 15 294 K 275 K MassDEP
  • Slide 5
  • Abbreviations and Definitions: UIC = Underground Injection Control GSHP = ground source heat pump = geothermal heat pump DX = direct exchange (ground portion of heat exchange occurs across a refrigerant loop) Dual use well = a well that is used as both a source of drinking water and heat pump supply Return flow = majority of the discharge from an open-loop heat pump Bleed flow = typically is 5% to 10% of the discharge from an open- loop heat pump that is not returned to the standing-column well gpd = gallons per day gpm = gallons per minute
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  • Know the regulations for your state Each of the New England states has a unique set of permitting, construction, withdrawal, and discharge requirements for geothermal heat pump wells
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  • New Hampshire Department of Environmental Services (NH DES) UIC registration required for all open-loop and closed loop systems individual registration form for single family residence other registration form for all other types of facilities Annual water quality monitoring requirements for open-loop wells
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  • NH DES (continued) With the exception of system bleed discharges, the following is not allowed: withdrawal from aquifer and discharge to surface water return flow to open-surface-infiltration
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  • NH DES (continued) Dual use not allowed for anything other than residential (1 to 2 units) Water Well Board requires a drilling license for the installers of closed-loop and DX wells Standing column return flow must be at least 50 feet below operating water level in well
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  • NH DES (continued) > 20,000 gallons in any 24 hour period averaged over 7 days, requires Water Use Registration applies to all open-loop wells (includes standing column with no bleed)
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  • NH DES (continued) > 57,600 gpd (40 gpm) design return flow plus bleed volume discharge requires both a Large Groundwater Withdrawal Permit and the development of a Water Conservation Plan eligible for waiver if actual return flow (including system bleed) doesnt exceed 57,600 in any 24-hour period also eligible for waiver if can demonstrate that water is returned to same aquifer withdrawal from bedrock aquifer and discharge to overburden aquifer is generally considered returning to same aquifer
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  • NH DES (continued) Open-pond loop not allowed unless applicant owns 100% of the surface water body
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  • Maine Department of Environmental Protection (ME DEP) UIC registration required for both open- and closed-loop wells Open-loop recommend heat exchanger to reduce threat of refrigerant release into the well in the event of a failure in the heat pump Closed-loop antifreeze propylene glycol grouting recommended
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  • ME DEP (continued) DX grouting recommended cathodic protection recommended Open-Pond Loops banned in Class A surface waters (nearly all of Maines surface water bodies are considered Class A)
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  • ME DEP (continued) Where PE license required, UIC registration is also required required for design of commercial GSHP systems if includes multiple heat pump units or if any unit exceeds a maximum cooling capacity of 5 tons or heating capacity of 200,000 BTUs exemptions for 1 to 2 family residences and farm buildings with overall floor plan
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  • ME DEP (continued) If discharging anywhere but to the same standing column well or municipal sewer system requires the following raw water laboratory analytical results from each supply well (unless can demonstrate hydraulic connection): If supplying well with make-up water from a different source, that source must also be tested for the above Recommend testing for lead and copper 90 to 120 days after system start-up unless using a heat exchanger ahead of the heat pump VOCs (EPA Method 8260) Diesel range organics Gasoline range organics Arsenic Lead Uranium Sodium Chloride Manganese
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  • ME DEP (continued) Well Driller Program requires that well drillers fix any problems associated with improper well construction require drilling and blasting rig operators to obtain a license to install GSHP wells registered drillers required to take a 2 to 3 day training course for GSHP certification (many existing drillers grandfathered) Additional changes expected in 2010 currently working on well construction requirements including grouting requirements and setback distances for closed-loop and DX wells
  • Slide 18
  • Vermont Department of Environmental Conservation (VT DEC) UIC Program only open-loop wells are required to obtain a UIC permit up to 25,000 gpd use eligible for a general permit but only if returning to the same aquifer > 25,000 gpd must obtain an individual permit administrative fee, review fee, and annual operating fee apply to both the general and individual permits temperature is the only water testing requirement VTs UIC regulation are currently being revised
  • Slide 19
  • VT DEC (continued) Groundwater Withdrawal Permit Exemptions for: residential use closed loop or standing column Existing groundwater withdrawals > 20,000 gpd (~14 gpm) withdrawal averaged over one month must file a groundwater report indicating the capacity, frequency, and rate of the withdrawal
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  • VT DEC (continued) Groundwater Withdrawal Permit (continued) New groundwater withdrawals beginning July 1, 2010 No new withdrawals of >57,600 gpd (40 gpm) for commercial or industrial uses without first obtaining a Groundwater Withdrawal Permit through VT DEC For existing withdrawals of >57,600 gpd (pre-July 1, 2010) increases in withdrawals of 25% of existing or increases of 57,600 gpd (whichever is smaller) requires a permit based upon highest historical use from 2005 2010 Permit process includes public notice and public meeting requirements
  • Slide 21
  • VT DEC (continued) VT requires permitting of private drinking water wells - dual use of private drinking water wells are handled differently in each region Well Driller Program well construction requirements apply for wells greater than 20 feet deep
  • Slide 22
  • Connecticut Regulations Connecticut regulations regarding GSHP wells are administered by several state agencies Department of Environmental Protection Department of Public Health Department of Consumer Protection
  • Slide 23
  • Connecticut Department of Consumer Protection (CT DCP) DCP has jurisdiction over the well drilling code recently attempted to pass GSHP regulations for open-loop, closed-loop, and DX wells but rejected by the state legislature currently GSHP requirements are determined at the individual town level
  • Slide 24
  • Connecticut Department of Public Health (CT DPH) Establishes set back distances for open-loop wells (same requirements as for private drinking water wells) Recommend that local boards of health require permits for closed-loop wells
  • Slide 25
  • Connecticut Department of Environmental Protection (CT DEP) DEP UIC Registration of discharge of Minor Heat Pump Water required for groundwater discharge of >/= 5,000 gpd and up to 50,000 gpd Monitoring required for lead, copper, zinc, oil & grease, & pH Monitoring frequency = Semi-Annually Discharge limits of pH = 5.0 9.0, and no visible oil sheen
  • Slide 26
  • CT DEP (continued) UIC registrations (continued) Surface water discharge of >/= 50,000 gpd and up to 500,000 gpd Monitoring required for lead, copper, zinc, pH, temperature, chlorine, salinity, hardness, and aquatic toxicity Monitoring frequency = Semi-Annually Discharge limits for pH, temperature, salinity, aquatic toxicity, and no visible oil sheen, floating solids, discoloration, or foaming Exemption for residential GSHP discharge No chemical additives allowed for UIC registration
  • Slide 27
  • CT DEP (continued) DEP Groundwater Withdrawal Permit Required for any groundwater withdrawal > 50,000 gpd unless returned to same aquifer within 250 feet from the withdrawal point
  • Slide 28
  • Rhode Island Department of Environmental Management (RI DEM) UIC permitting only required for non-residential open-loop GSHP wells Setback distances are shown on the UIC application form
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