|Source: California Energy Commission|
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3. Proposed Revisions - Residential
6. Success Criteria
- Policy Drivers
- Governor's “Clean Energy Jobs Plan”
- Zero Net Energy: Residential by 2020 and Nonresidential by 2030
- CARB Climate Change Scoping Plan
- California Long Term Energy Efficiency Strategic Plan
- 2016 Standards Update Process
- April 4, 2014 - CBIA/CEC Standards Forum
- April – May 2014 - IOU CASE Stakeholder Meetings
- May – Aug 2014 - CEC Staff Public Workshops
- November 2014 - Draft 2016 Standards
- January 2015 - Release 45-day Language
- April 2015 - Release 15-Day Language
- May 2015 - Adoption at CEC Business Meeting
- January 1, 2017 - Effective Date of the Standards
- ACM - Alternate Calculation Method - California Building Energy Efficiency Standards for Low-Rise Residential Buildings allow compliance by either a prescriptive or performance method. Performance compliance uses computer modeling software to trade off efficiency measures. For example, to allow more windows, the designer will specify more efficient windows, or to allow more west-facing windows they will install a more efficient cooling system. Computer performance compliance is typically the most popular compliance method because of the flexibility it provides in the building design.
- B/C - Benefit to Cost Ratio - Important metric in determining revisions to Title 24
- CASE - Codes And Standards Enhancement - Through CASE Reports, the IOUs will provide the California Energy Commission with the technical and cost-effectiveness information required to make informed judgments on proposed standards for promising energy efficiency design practices and technologies. Stakeholder Meetings provide an opportunity for stakeholders to help inform the development of these codes change proposals. The IOUs encourage participation in this step of the process through the submission of data— both primary sources and references to existing data, e.g., reports, spreadsheets, etc.
- CZ - Climate Zone - 16 zones in California used by the California Energy Commission to determine which energy efficiency measures are appropriate in which environment. In more moderate climates along the coast, certain energy efficiency investments may not be economic.
California Climate Zones
- DCS - Ducts in Conditioned Spaces
- HPA - High Performance Attic
- J-Curve - Goal is to maximize efficiency with no increase in total life cycle cost (LCC)
Source: CEC Staff Workshop on Proposed Efficiency Measures for Nonresidential Buildings June 12, 2014
- LCC - Life Cycle Costs - The legislation authorizing Title 24 requires “The standards adopted or revised pursuant to subdivisions shall be cost-effective when taken in their entirety and when amortized over the economic life of the structure compared with historic practice. When determining cost-effectiveness, the commission shall consider the value of the water or energy saved, impact on product efﬁcacy for the consumer, and the life cycle cost of complying with the standard.”
- Discounted cash flows for costs and benefits
- Accounts for maintenance costs/benefits
- Appropriate discount rates and life of measures - 30 years for residential measures
- LPA - Lighting Power Allowance - The maximum allowable lighting density permitted by the code. It is expressed in watts per square foot for a given occupancy/space type
- LPD - Lighting Power Density - Technically represents the load of any lighting equipment in any defined area, or the watts per square foot of the lighting equipment. However, in the lighting industry it is often associated with the lighting power allowance (LPA) permitted by the building energy code in question.
- TDV - Time Dependent Valuation - The TDV factors are used to evaluate the cost-effectiveness of energy efficiency measures in buildings. The metric values energy efficiency based on when energy savings occur, reflecting the variations over time in the cost of energy production and delivery. Based on hourly (or monthly) cost of energy, scaled to rates and climate zone sensitive
- Value of gas and electricity changes depending on the season and the time of day
- 8,760 TDV multipliers for each hour of the year
- Favors measures that save energy during high demand periods
3. Proposed Revisions - Residential
- TDV -
- 1. Develop hourly 15-year and 30-year forecasts of avoided cost of energy
- Residential and Nonresidential Electricity Costs
- Residential and Nonresidential Natural Gas Costs
- Residential and Nonresidential Propane Costs
- 2. Calculate net present value (NPV) of cost stream - 3% real discount rate (at 2% inflation = 5% nominal)
- 3. Convert NPV costs ($/unit energy) into TDV energy factors (kWh/kBtu for electricity)
- Incorporate assumptions from the 2013 Integrated Energy Report (IEPR)
- Natural gas cost to electric generators
- Marginal energy costs under various demand and generation scenarios
- GHG costs
- Electric and natural gas rate forecasts
- Update hourly electric marginal cost of energy
- Incorporate Effective Load Carrying Capability (ELCC) method for electric generation capacity allocation factors
- Update electric T&D marginal costs
- Residential Lighting -
- High efficacy lighting has been cost effective since the 2005 Standards
- Adoption of high efficacy lighting is still low
- Energy savings from low efficacy lighting with controls is far less than the savings from high efficacy lighting
- 81% of installed watts are low efficacy
- 62% of installed lamps are low efficacy
- 70% of sockets are low efficacy
- Barriers to High Efficacy Lighting
- Quality of high efficacy sources - Color quality is a common complaint for CFLs
- Limited high efficacy fixture choices
- Inflexible and unfamiliar sources – GU-24 or pin-base CFL – Integral LED luminaires
- Higher costs for currently defined high efficacy luminaires efficacy luminaires – Higher costs for luminaires – Higher costs for replacement lamps - Higher costs for replacement lamps
- Proposed Code Change: Simplify the Residential Lighting Standard
- Require High Efficacy Residential Lighting Standards
– In all room types
– Eliminate low efficacy allowances with controls
- Relax High Efficacy Definition - Allow traditional (e g screw Allow traditional (e.g. screw-base) socket types but only if base) socket types, but only if installed with high quality, high efficacy, JA-8 source
- All hardwired or GU-24 options in Table 150.0-A remain
- Recessed Downlights only luminaire type not allowed to use JA-8 compliant screw base lamps
– JA8 dedicated luminaire, or use quick-connect or Zhaga base
- Maintain Existing Control Requirements
– At least one luminaire in Bathrooms, Laundry, Utility Rooms, and Garages must be controlled by vacancy sensor
– Dimmers or vacancy sensors required for screw-base LED fixtures in all room types other than Kitchens Bathrooms fixtures in all room types other than Kitchens, Bathrooms, Laundry Rooms, Utility Rooms, and Garages
|Source: Staff Workshop on Proposed Lighting Efficiency Measures for Residential and Nonresidential Buildings|
June 24, 2014
- Residential High Performance Attics / Ducts in Conditioned Spaces (HPA/DCS) - This proposed measure is a modification to the prescriptive residential building requirements to allow two methods of saving energy. Heating and cooling air distribution losses in a central forced air system significantly reduce efficiency. Duct sealing has been addressed but the negative impact of ducts located above the insulation in attics remains to be addressed. One part of the proposal introduces a prescriptive requirement for the location of duct work and equipment in residential and low-rise multifamily buildings. The other part includes an alternative prescriptive requirement that focuses on the performance of duct and attic characteristics.
The measure consists of two alternatives for accomplishing improved envelope characteristics and reduced HVAC distribution losses. These two approaches will have similar energy impacts on the building.
- High Performance Attics (HPA) implements a package of measures that minimizes the temperature difference between the attic space and the conditioned air being transported through ductwork in the attic. It also reduces heat transfer through the roof into the attic. The option will include additional components needed to achieve the required reduction in distribution losses including very low leakage (<4%) ducts and air handler system and highly insulated ducts.
- Ducts in Conditioned Space (DCS) locates ducts inside the building’s thermal and air barrier envelope. The DCS criteria can be met by: ductless systems such as Multi Mini Split heat pumps or radiant hydronic heating and cooling; ducts and equipment in a sealed attic; ducts in dropped ceilings and equipment in an interior mechanical closet; and other alternative approaches discussed below.
- Residential High Performance Walls - Proposed Prescriptive U-factor ~0.05 for exterior walls CZs 1-6 and 8-16
The Residential High Performance Walls measure is intended to increase the performance of the residential envelope, reducing the amount of heat transfer through walls and thus reduce HVAC loads. The CASE Team is investigating two changes to the Standards: mandatory Quality Insulation Installation (QII) for fiberglass batt insulation; and improved prescriptive wall insulation requirements.
QII Mandatory for Batt Insulation
The IOU C&S team intends to add mandatory requirements for QII when fiberglass batt insulation is installed, which will require verification by a HERS rater or Building Performance Institute (BPI) Building Analyst to ensure proper insulation installation within the entire thermal envelope. Currently, a compliance credit is awarded for installations that verify QII. This proposal would require QII for batt insulation, while still allowing a compliance credit for QII with other types of insulation. Field surveys have found that the most commonly used wall insulation in California are fiberglass batts. Requiring QII for batt insulation would ensure that the majority of insulation installations are properly implemented, increasing the effective U-factor of these wall assemblies.
This measure would modify the mandatory requirements, remove the current compliance credit for QII with batt insulation, and revise the corresponding standard energy budget in the prototype model. The measure would also update Joint and Residential Appendices language, and compliance forms, as related to QII requirements. This measure modifies existing code language, but does not modify the scope of the Standards.
Wall Assembly Strategies
This measure also lowers the prescriptive whole wall insulation U-factor requirements for wood framed walls in residential and low-rise multifamily buildings. The CASE team is investigating the feasibility of lowering U-factor requirements while considering the variety of framing and cavity insulation strategies available to reach lower U-factors. These strategies include: These wall designs allow for greater R-values for cavity insulation, quality installation that fills all gaps and does not compress insulation, and, in some cases, reduced thermal bridging. Currently, these types of framing techniques are compliance options in the performance approach for the 2013 Title 24 Standards. The use of batt, blown-in, spray foam, flash-and-batt, and continuous (rigid) insulation with these wall types were assessed. This measure affects the prescriptive requirements and related modeling algorithms for standard walls. This measure modifies existing code language, but does not modify the scope of the Standards.
- Tankless Water Heaters - The Instantaneous Water Heaters measure proposes to modify the prescriptive requirements for gas domestic hot water systems in newly constructed single-family buildings and multi-family buildings with dedicated water heaters for each dwelling unit. The current prescriptive approach allows the use of either gas storage water heaters or tankless gas water heaters. The proposed measure would modify the language by specifying that the Energy Factor (EF) of the water heater would have to be at least as high as the federal minimum EF for tankless gas water heaters (EF = 0.82). Buildings using the performance approach to comply with the standards could deploy a number of strategies to achieve the energy budget for water heating, including installing a high-efficiency condensing gas storage water heater.
Since tankless gas water heaters have higher EF ratings than storage-type water heaters and water heating accounts for the largest share of energy usage in a home, the proposed prescriptive requirement is anticipated to garner significant energy savings for California.
This measure builds upon the high-efficiency water heater (HEWH) ready measure that was adopted into the 2013 Title 24 standards (effective date July 1, 2014). The HEWH standards requires domestic water heating systems in new residential construction (single-family and multi-family buildings with dedicated water heaters in individual dwelling units) to be designed to accommodate condensing gas storage and tankless gas water heaters. By the time the 2016 Title 24 standards take effect in 2017, builders will be accustomed to designing for higher-efficiency water heaters. High–efficiency water heaters have also been proven to be cost-effective in all climate zones across California.
The IOU Codes and Standards Team is seeking feedback on the feasibility of revising the prescriptive requirements for domestic hot water heating systems in single-family buildings and multi-family buildings with dedicated water heating units for each dwelling unit. In particular, feedback is desired on current construction practice, on relative costs of insulation techniques, and on design issues of advanced construction assemblies, if any, not directly related to cost.
- Residential HVAC Field Verification and Diagnosis - The Residential HVAC Field Verification and Diagnostics measure is intended to reduce inefficiencies in residential HVAC (heating, ventilation, and air conditioning) equipment by improving fault testing procedures and air flow efficiency requirements. Laboratory work has shown the impact of refrigerant charge levels on energy efficiency can be significant.
Most residential air conditioners and heat pumps are split systems with an inside coil and an outside compressor bearing unity which are connected with refrigeration tubing. Systems are installed on-site, far from the production line and manufacturing quality control. Though manufacturer’s installation manuals instruct the technician how to safely and correctly assemble and then charge the system, many of the new air conditioners in California fail to achieve their rated efficiency due to improper amounts of refrigerant, improper evacuation, metering device malfunctions, and other problems. The impact of this degraded performance on the life cycle cost may be large statewide. The 2005, 2008 and 2013 Title 24 code cycles have required that refrigerant charge is done according to a superheat or subcooling protocol, which is verified by a HERS rater. According to a 2012 study, technicians in the field may not understand how to test, diagnose, and repair faults properly.
These faults are often related to refrigerant charge. Modifications and additions are proposed to improve the 2013 code for industry input, including the following:
4. Benefits -
- Green Job Creation - Most new jobs should and will be created in the private sector, but government can play an important role in establishing a favorable climate for job creation.
- Higher Paying Jobs
- Investment By Entrepreneurs
- Global Competitiveness
- “Energy Efficiency is the cheapest, fastest, and most reliable
- way to create jobs, save consumers money and cut pollution
- from the power sector.” Governor Jerry Brown
- More Efficient Buildings… Require the manufacturing, design, installation, monitoring and maintenance of efficient systems and technologies,
- Establish a plan and timeline to make new homes and commercial buildings “Zero Net Energy”
- Highly efficient structures that use onsite renewable energy for all their electricity and natural gas needs
- Design new more efficient buildings that use half the energy they compared to the 2008 Standards home
- CEC - California Energy Commission - Workshops, Notices, and Documents 2016 Building Energy Efficiency Standards Pre-Rulemaking
- Energy and Environmental Economics, Inc. - San Francisco-based consulting firm since 1989. Experienced in linking technical-economic analysis to policy decision-making and public process. E3 worked on the 2005 and 2008 Title 24 TDV
- Energy Solutions - Oakland, CA - Experience includes evaluating emerging technologies, benchmarking building energy use, conducting energy audits, acting as owner’s representative, designing and implementing energy efficiency programs, developing and defending state and federal appliance and building standards, and developing marketing strategies to maximize program impacts.
Michael McGaraghan, Energy Solutions firstname.lastname@example.org - Residential Lighting
- http://title24stakeholders.com/ -
- TRC Solutions - Lowell, MA - A national engineering, consulting, and construction management firm that provides integrated services to the energy, environmental and infrastructure markets.
David Douglass-Jaimes, TRC email@example.com - Residential Lighting