AgdaPkt 2019-09-23 Joint SA PFA - Laserfiche WebLink

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MEMORANDUM (continued) To: Gabriel Taylor and Peter Strait (CEC) Re: Interpretation of Menlo Park Reach Code September 3, 2019 be allowed for cooking or decorative fireplaces is a voluntary choice to be made by a homeowner/builder and as such does not need to be shown to be cost-effective. Additionally, the cost to add pre -wiring for cooktops/ovens is minimal at the time of new construction since there is an electrical outlet present even for gas cooktops since they are electronic/electric ignition and have other electronic components like fans and lights that need electricity supply. So, the pre -wiring for future induction cooktops only requires upsizing the wire gauge (a minimal cost at time of construction) and a different outlet (also a minimal upgrade cost). A recent cost -estimate provided by Scott Shell at EHDD Architects (based on data provided by tbd consultants) estimates this cost to be $280 at the time of new construction. Retrofitting an existing electrical line with an upsized one that can power induction would cost $930. So, it is inherently cost-effective for the lesser expense be done at time of construction as opposed to spending more year or more later to add the capability. ♦ The cost-effectiveness study conducted by TRC for the Statewide Codes and Standards Team at the Investor Owned Utilities (IOU) used a hotel prototype for establishing cost-effectiveness for both hotel as well as high-rise residential applications. This is partly because there was no high- rise residential prototype available and the Title 24 compliance tools lack modeling of central water heating systems. Since the Title 24, part 6 requirements for hotel/motel guestrooms are the same as those of high-rise residential dwelling units, and because the prototype was modeled with individual space and water heaters, we believe the use of the hotel prototype is appropriate to represent high-rise residential as well. Further, any nonresidential spaces modeled for the hotel prototype would have to be modeled with same/similar systems if those same end uses exist in a high-rise residential building. Thus, we are confident that the hotel prototype is sufficient for high-rise residential applications. In nonresidential buildings, the prototypes examined in the cost effectiveness analysis only included space heating and water heating electrification. Other end uses targeted in the Menlo Park ordinance are unregulated appliances such as cooking, clothes drying which are not explicitly modeled in Title 24 compliance calculations. Adding requirements for these end uses to be electric does not impact the TDV budget for the building or compliance with Title 24. These will however impact the overall fist cost of the all -electric building as well as operational impacts. These impacts however are not likely to be significant compared with the overall cost savings of around $25,000 for offices and retail and almost $1M for hotel occupancies. Electric cooking and clothes drying first cost difference compared to natural gas versions are between $800-$2000 per appliance. Operational cost increases are around $2,000 per appliance over the building's lifetime. Thus, the added first and operation costs for electric appliances are unlikely to be greater than the significant cost savings resulting from eliminating natural gas infrastructure. We thus propose that existing cost-effectiveness studies should be sufficient to justify Menlo Park requirements. Any guidance on this approach and/or code language format is much appreciated. Page 2 of 2 ,/ TR