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Home My WebLink AboutFile Documents.865 Moore Dr.0067.2016 (3).ARBK May 29, 2014 Sent via Email SUBJECT: Request for Exception to RREMP Credit for Ground Source Heat Pump Equipment per City Ordinance #11 For new residence at 865 Moore Drive, Lot 6, Five Trees TO: Stephen Kanipe 8295 South Krameria Way CC: Denis Murray Centennial, CO 80112‐3004 The purpose of this letter is request an exception to the allowable credit for ground source heat pump (GHP) equipment per City of Aspen Ordinance 11, Section 301.3. The requested exception will provide $2,800 per 10,000 BTU per hour of system capacity – twice the current allowance for GHP equipment. The basis for this request is to develop three years of performance data specific to Aspen for the use of high temperature vapor injection heat pumps for snow melt applications, and to validate ACCA Manual J predictions for heating and cooling tight super insulated homes. The proposed equipment for the Schlief family residence to built at 865 Moore Drive, Lot 6, Five Trees exceeds the requirements of City of Aspen Ordinance 11, Section 301.3. The coefficient of performance (COP) for the GHPs exceed 3.0 with 6,750 square feet (83%) of the total 8,150 square feet of snow melt provided by geothermal equipment. A 94% efficient condensing boiler will provide heating for the remaining 1,400 of snow melt. The GHP equipment rated at 10 tons (120,000 BTU/hr) for heating and cooling is sized to meet 100% of the Manual J peak heating load of 114,914 BTU/hr and the peak cooling load of 38,886 BTU/hr. A dedicated water‐water GHP provides 40,000 BTU/hr of heating domestic hot water at 200% capacity. Under the City of Aspen stricter design guidelines, these heat pumps operate at a COP of 3.4, exceeding the COP 3.0 standard by 14%. The AHRI/ISO ratings range from 3.5 to 5.3 COP, and exceed the standard by 17% to 77%. The proposed structure is primarily heated and cooled with a hydronic in‐floor system using passive ground loop fluids for cooling without compressor operation. All heat pumps operate at a COP exceeding 3.0 at an entering source water temperature maximum of 30 degrees and leaving load water temperature minimum of 110 degrees. The following attachments provide documentation to in support of the above statements: Attachment 1 ‐ ACCA Manual J heating and cooling load calculations (Wrightsoft) Attachment 2 ‐ AHRI/ISO GHP AHRI/ISO performance data Attachment 3 ‐ Snow melt heat loss load calculations (comparable to Manual J) Attachment 4 – Geothermal Heat Pump and Boiler Equipment Schedule The summary of RREMP Total Fees for Mitigation is provided as a two part attachment in order to delineate the portions of the RREMP fees associated with 6,750 SF of snow melt and 35 SF of spa usage using geothermal equipment at 100% efficiency, and 1,400 SF of snow melt with a 94% efficient boiler. Attachment 5 contains the City of Aspen spreadsheet to determine the RREMP fee and the on‐site renewable energy credits required to offset these fees with geothermal heat pump equipment. The BTU/hr credits were calculated at 50% of the RREMP fee to account for a 2x credit exception. 05/29/14 The following table summarizes the data contained at Attachment 5 in order to illustrate a Total Fee for Mitigation of $286,298 for 8,150 SF of snow melt using a combination of GHP and boiler equipment. Summary of RREMP ‐ Total Fee for Mitigation Snowmelt SF Spa SF Boiler Efficiency REMP Payment Atch 5 ‐ Part 1 6,750 35 100% $235,660 Atch 5 ‐ Part 2 1,400 94% $50,638 8,150 Total $286,298 On‐Site Renewable Energy Credits Quantity BTU/hr REMP Credit Atch 5 ‐ Part 1 841,643 BTU/hr Ground Source Heat Pump $117,830 Atch 5 ‐ Part 2 180,850 BTU/hr Ground Source Heat Pump $25,319 1,022,493 BTU/hr Total Credit at $1,400 per 10,000 BTU/hr $143,149 2x Credit ‐ $2,800 per 10,000 BTU/hr $286,298 The on‐site renewable credits required to offset the $286,298 RREMP fee is 1,022,493 BTU/hour peak capacity from the geothermal heat pump equipment. Restated using language from the City of Aspen Ordinance 11, Section 301.3, at $1,400 per 10,000 and multiplied by the 2x credit exemption requested, the $286,298 fee requires 102.2 units of 10,000 BTU/hr at $2,800 per unit. The following table shows installed GHP capacity of 131 units of geothermal on‐site renewable energy credits (1,309,000 BTU/hr) which more than offsets the Total Fee for Mitigation of the $286,298. Geothermal Equipment Capacity Offset Unit ISO COP Capacity BTU/hr Quantity Total BTU/hr Snow Melt NEW066 Vapor Injection 4.4 83,000 14 1,162,000 HVAC NVV036 7 Series VS 3.5 32,000 2 64,000 NDZ026 5 Series Split 3.9 19,500 2 39,000 DHW NEW040 Vapor Injection 4.6 44,000 1 44,000 1,309,000 Required Peak BTU Offset 1,022,493 GHP Capacity in BTU/hr Exceeding RE Credit Requirement 286,507 While the geothermal equipment provides sufficient offset for RREMP, the primary purpose of this exception request is to substantiate the published performance of high temperature evaporative vapor injection (EVI) heat pumps in a snow melt application. In concert with this requirement, validating the performance of a high efficiency building envelope against Manual J heat loads is invaluable. 05/29/14 To provide the City of Aspen with performance data on snow melt and heating, cooling and hot water loads using geothermal equipment, this exception request includes the provision for energy monitoring and reporting. The proposed installation will include monitoring devices in order to provide the City of Aspen with quarterly reporting for three years for energy and performance data on this home: 1. Meter BTU output for total snowmelt, boiler, and geothermal water‐to‐water 2. Meter electrical energy input to boiler and separately, electrical energy to geothermal water‐ water heat pumps used for snow melt (for the purpose of calculating actual COP) 3. Submeter utility room electrical usage from overall building electrical loads (for the purpose of comparing Manual J building load predictions with actual energy use). This will be accomplished physically by installing electrical subpanel dedicated to building heating, cooling, hot water, and snow melt equipment. 4. Monthly energy input and output for monitored equipment, and BTU output dedicated to snow melt by month with associated runtime and outdoor air temperature. This information may be transmitted electronically in digital format. CERTIFICATION The City of Aspen Ordinance 11 requires that RREMP calculations and offset requests be performed by an individual with Colorado State, IGSHPA, and AEE certifications. Attachment 6 contains my certifications with the following qualifications: 1. Colorado Department of Water Resources Certification GT‐66, Permit 55‐GX 2. AEE Certified GeoExchange Designer (CGD) 286 3. IGSHPA Certified Installer 21357‐0402 RREMP EXCEPTION REQUEST With the goal to validate the technology proposed above to reduce carbon emissions and energy use, I am respectfully requesting that the City of Aspen approve as a one time exception the 2x multiplier for geothermal offset from $1,400 to $2,800 per 10,000 BTU/hr geothermal capacity. Warm regards, Albert R. Wallace President, CEM, CGD Phone (303) 877‐5776 Email – alwallace@covad.net 05/29/14