Climate Action Plan and Ground Source Heat Pump GHG Emission Study Preliminary Results October, 17 th Aspen, CO Jeff Lyng, Renewable Energy Program Manager The Mission of the Governor s Energy Office is to lead Colorado to a New Energy Economy through energy efficiency, renewable and clean energy resources
20% Reduction in Greenhouse gas emissions from 2005 baseline by 2020.
Climate Action Plan What s the goal? As Modeled MMTCO2 2005 48,353 GWh 44.53 2020 Business as Usual 69,008 GWh 63.56 20% below 2005 35.63 Savings needed by 2020 27.94 50% of 2020 Goal 13.97
Climate Action Plan What s the goal? our challenge
Climate Action Plan 20% reduction in CO2 emissions from the utility sector by 2020
Climate Action Plan 50% of utility sector CO2 reductions will be from efficiency
Why Buildings? 76% of all power plant generated electricity is used just to operate buildings. Buildings Account For Half Of All Greenhouse Gas Emissions.
EVALUATION OF GROUND SOURCE HEAT PUMP ENERGY AND GREENHOUSE GAS EMISSIONS REDUCTION POTENTIAL IN RESIDENTIAL COLORADO APPLICATIONS Study conducted by the University of Colorado at Boulder
Problem Statement Ground source heat pump (GSHP) technology provides high efficiency option for electric heating and cooling High efficiency does not necessarily imply lower green house gas (GHG) emissions What combination of efficiency level and electricity generation mix ensures reduced GHG compared to conventional HVAC? What are the effects of climate?
Literature Review Three studies concerning residential GSHP systems reviewed: Modeling study conducted for Minnesota predicted almost no demand savings and a large increase in CO2 emissions Texas study predicted demand and energy savings based on GSHP EER rating and location 16.8 and 18.3 EER GSHP systems showed demand and energy savings All but one 12.4 EER system showed negative demand and energy savings (increase) Study looking at GSHP potential in Canada predicted blanket CO2 emission reductions COP of 3.3 and EER of 14.1 used. Was not a very technical study No consensus on GSHP demand or CO2 reduction potential. Could be system and/or site specific.
Building Simulation Model equest Version 3.61 (DOE 2.2) used to simulate performance Conforms to Building America Research Benchmark Model (minus HVAC systems) generated by Scott Horowitz at the National Renewable Energy Lab using BEopt and provided specifications Model specifications: 4 occupants 4 bedroom/3 bath 9 foot ceilings Aspect ratio of 1.5 5:12 roof pitch 100% garage protrusion
Location Summary Location Number of Heating Degree Days (65 F) 6,128 Altitude (ft) Latitude ( N) Longitude ( W) Denver Number of Cooling Degree Days (65 F) 695 5,284 39.739-104.984 Alamosa 44 8,736 7,539 37.469-105.869 Aspen 35 8,835 7,908 39.191-106.816 Colorado Springs 404 6,480 6,012 38.834-104.821 Craig 42 8,351 6,876 40.515-107.546 Durango 238 6,779 6,686 37.275-107.879 Fort Collins 497 6,238 5,000 40.585-105.084 Grand Junction 1,091 5,489 4,839 39.063-108.55 Lamar 1,088 5,556 3,704 38.087-102.620 Trinidad 653 5,111 5,761 37.169-104.5
Examined HVAC Systems Six different HVAC systems have been simulated for each location. 78 AFUE furnace only 90 AFUE furnace only 78 AFUE furnace & an evaporative cooler 78 AFUE furnace & a 13 SEER air conditioner Also running baseboard electric radiator in next modeling iteration Vertical well GSHP with a COP of 3.3 and a cooling EER of 14.1 SLINKY GSHP with a COP of 3.3 and a cooling EER of 14.1 Each HVAC model was run twice so that natural gas and propane based furnaces could be simulated.
Electric Demand Results The annual peak electric demand for most GSHP systems occurred in the winter. The GSHP increased peak summer demand for 7 of the 10 locations compared to the 78 AFUE furnace & A/C system demand. Summer demand: June Sept., 2:00pm - 7:00pm (consistent with Xcel Energy SG Rate peak hours)
Summer Peak Demand vs. Location and System Type 7.0 6.0 Xcel Peak Demand (kw) 5.0 4.0 78 AFUE + A/C Vertical GSHP 3.0 SLINKY GSHP 2.0 1.0 0.0 Denver Alamosa Aspen Colorado Springs Craig Durango Fort Collins Grand Junction Lamar Trinidad
Annual Peak Electric Demand by Date and Time 12:00 AM 10:00 PM 8:00 PM 6:00 PM 4:00 PM 2:00 PM 78 AFUE + A/C 12:00 PM Vertical GSHP SLINKY GSHP 10:00 AM 8:00 AM 6:00 AM 4:00 AM 2:00 AM 12:00 AM 1/1 2/10 3/21 4/30 6/9 7/19 8/28 10/7 11/16 12/26
Energy Results GSHP decreased natural gas consumption (or propane consumption) for all locations GSHP increased electricity consumption for all locations.
Natural Gas Consumption Comparison 200,000 180,000 Natural Gas Consumption (kbtu/year) 160,000 140,000 120,000 Vertical GSHP 100,000 SLINKY GSHP 78 AFUE Furnace & A/C 80,000 60,000 40,000 20,000 0 Denver Alamosa Aspen Colorado Springs Craig Durango Fort Collins Grand Junction Lamar Trinidad
Electricity Consumption Comparison 25,000 Annual Electricity Usage (kwh/year) 20,000 15,000 Vertical GSHP SLINKY GSHP 78 AFUE Furnace & A/C 10,000 5,000 0 Denver Alamosa Aspen Colorado Springs Craig Durango Fort Collins Grand Junction Lamar Trinidad
CO2 Emission Results Vertical well and SLINKY GSHP reduce CO2 emissions when: Average emission reductions* of: Compared to natural gas based 78 AFUE furnace & A/C system. Compared to propane based 78 AFUE furnace & A/C system. For all 10 locations. 3,800 lbs/year vs. natural gas based system 6,070 lbs/year vs. propane based system CO2 savings seen to increase as electricity generation mix becomes cleaner. *Assuming 2004 Colorado generation mix.
Annual Denver CO2 Savings vs. Generation Mix 14,000 12,000 CO2 Savings (lbs/year) 10,000 8,000 6,000 Vertical GSHP 4,000 2,000 0 SLINKY GSHP
Annual Denver CO2 Savings vs. Electric Generation Emission Factor 14,000 12,000 CO2 Savings (lbs/year) 10,000 8,000 Vertical GSHP 6,000 SLINKY GSHP 4,000 2,000 0 0.00 0.50 1.00 1.50 Electric Generation CO2 Emission Factor (lbs/kwh) 2.00 2.50
Annual CO2 Emission Comparison (2004 Colorado Emission Base) 60,000 Annual CO2 Emissions (lbs/year) 50,000 40,000 Vertical GSHP 30,000 SLINKY GSHP 78 AFUE Furnace & A/C 20,000 10,000 0 Denver Alamosa Aspen Colorado Springs Craig Durango Fort Collins Grand Junction Lamar Trinidad
Annual CO2 Savings vs. GSHP Type 7,000 6,000 CO2 Savings (lbs/year) 5,000 4,000 Vertical Well GSHP SLINKY GSHP 3,000 2,000 1,000 0 Denver Alamosa Aspen Colorado Springs Craig Durango Fort Collins Grand Junction Lamar Trinidad
Impact of System Type and Location on Annual Energy Cost $3,100 $3,000 $2,900 $2,800 $2,700 78 AFUE Furnace with Air Conditioner 78 AFUE Furnace with Evaporative Cooler Ground Source Heat Pump - Slinky Ground Source Heat Pump - Vertical $3,000-$3,100 $2,900-$3,000 $2,600 $2,800-$2,900 $2,500 $2,700-$2,800 $2,400 $2,600-$2,700 $2,300 $2,500-$2,600 $2,200 $2,400-$2,500 $2,300-$2,400 $2,200-$2,300 Both GSHP systems provide annual energy cost savings (vs. A/C system) for every location.
Summary GSHP detractors: Increase peak summer demand Increase electricity usage GSHP benefits: Reduce energy costs for the consumer Reduce CO2 emissions Decreased natural gas (or propane) consumption
Next Steps Complete CU Boulder study with empirical data model validation. Lifecycle analysis with reasonable fuel escalation rates Determine the best pre and post conditions to implement GSHP technology. Soil thermal properties for 10 sites Find and develop financing for electric utilities to develop demand side management programs to promote GSHP where advantageous
GEO Needs Your Help to Develop Grounds Source Heat Pump Case Studies GEO is compiling a database of Size, description, performance data, installer & manufacturer, etc. Case studies of typical R&C systems across the state Geothermal Trade Ally Asset Map National, regional, statewide resources to promote GSHP technology in Colorado If you have data to share for this effort, please contact Ed Thomas, Market Development Group, (970) 209-8347, ethomas@marketdevelop.com
Please call or email with questions: Jeff Lyng Governor's Energy Office 225 East 16th Avenue, Suite 650 Denver, CO 80203 P: (303) 866-2264 F: (303) 866-2930 www.colorado.gov/energy Jeff.lyng@state.co.us