DHP for New Construction: How to establish the baseline Adam Hadley and Phillip Kelsven RTF Subcommittee December 4, 2015

Overview Today, we are seeking input on how to establish the baseline heating system type for a new measure “New Construction DHP” Efficient-case heating system would be: – DHP/Zonal Electric Hybrid With a DHP in the main living area of the house – All DHP Maybe with short duct runs? Primary Difficulty in establishing the baseline heating system type: In New Construction, builders often have many choices for heating system types – Our question: What system would they have installed if they hadn’t installed the DHP/hybrid system? 2

The importance of establishing the baseline: Gas and other non-electric fuels make up a large part of the market, which would cut into electric savings 3

Other Ideas? Are there certain reasons a builder would choose DHP that would cause a different baseline mix than that found in the general market? – In other words, are houses that receive DHP’s “special” in some definable way? For example, do builders only consider installing DHP’s where gas isn’t available? Or where an electric heating system is being considered? Or??? Could we collect usable data by interviewing builders and their HVAC contractors? – “Under what circumstances do you install DHP’s in new houses?” » Is cost a consideration? Examples? » Is gas availability a consideration? » Is house floorplan a consideration? » Is climate a consideration? » Do customers request zonal? – “Where you’ve installed DHP/hybrid systems, what was the most likely alternative heating system type and why?” » “Why didn’t you choose ____ system type?” 4

s – David Bopp Very few new houses with DHP’s Entry level houses tend to use electric FAF rather than gas FAF – Hookup fee about $1800 from the curb – Upgrade is ducted ASHP (provides AC + efficiency) Builders considering DHP/Zonal as a cheaper option; one house: – $2,300 more than ducted electric FAF w/o AC – $3,300 less than ducted ASHP – Habitat was doing ducted ASHP’s, but shifted to dual head ductless recently. With DHP/zonal + HRV is slightly more expensive than ASHP, but the performance seems to be much better Expects to see DHP/zonal in small homes with open floor plans, and entry level builds Forced air is what people are comfortable with (for now) 5

s – Thomas Anreise Scenarios – DHP/Zonal instead of Zonal Value-add for small/starter homes, affordable housing, gas not available – DHP instead of gas FAF Local factors matter – Gas hookup costs – Alternative to gas FAF where market resists ASHP – Multi-head systems seen as alternative to central systems in more DHP-mature areas – Buyer avoids cost of adding AC to the furnace – DHP instead of ASHP Use of DHP allows code or program requirements to be met more easily – Simpler load calc and system selection process – Eliminates or reduces duct design and testing requirements – Minimizes commissioning requirements – Simplifies compliance with “ducts inside” requirement Cost and floor plan are considerations – DHP’s cost same ore less than central systems – Homes are not necessarily smaller Program or contractor help builder design system (placement, orientation, # of heads) 6

s – Eli Volem What is the baseline for existing new construction ducted heat pump measures? – Proposed answer from Adam Hadley The RTF does not have a heat pump “conversion” measure for new construction for the same reason we’re struggling with DHP’s in new construction: the baseline heating system type is unknown Energy Star models a DHP/Zonal system as if it were a ducted heat pump without duct leakage – Maybe this could work for new construction DHP’s Builders have used DHP’s in the Energy Star program – This is the only support the utility has been able to give so far, but it hasn’t achieved a large number of homes – Hope to be able to offer DHP in new construction – Only one builder building non Energy Star home with a DHP Main motivation probably low cost with efficiency and cooling benefits 7

s – Rich Arneson Tacoma staff seeing same things as David and Thomas Generally if gas is available, builders go with gas – “AC Ready” is common Zonal electric homes tend to be smaller and lower cost Recommend not pursuing this measure as a multi-head DHP system Haven’t been seeing ducted electric FAF in new homes Ducted central ASHP tend to go in custom homes – Spec built homes are gas or zonal electric if gas isn’t available Home size might not be the right factor – DHP serves common area, primarily; the size of this area might be a more appropriate metric 8

s – Phillip Kelsven/Eli Volem ETO has an incentive for DHP in new construction – ETO assumes program does not influence fuel choice – ETO assumes electric resistance baseline only (not via to all) – ETO Blessing Memo Summary (June 27, 2013) Stand alone measure for new construction – Expect small scale participation prior to moving to EPS program and BOP packages Incentive: $400 Allowed in homes up to 1,800 square feet One DHP may be installed (one-to-one unit) – Inverter-driven, no built-in electric resistance heat, ARI listed – Must be primary heating equipment and sized to provide heating requirement down to 17 deg F or local design temp (whichever is greater) – Supplemental heat for bedrooms is allowed, cannot exceed 100% of design load – Paul Sklar to look into program participation, looking for insights into baseline question… 9

Next Steps What should a research strategy look like to answer the baseline question? – Builder interview sound right? How many interviews? “Must-have” questions? Are there particular ways the measure should or should not be defined? – “Applies where gas is not available” – Others? 10