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Base Load Measures. WEATHERIZATION ENERGY AUDITOR SINGLE FAMILY. WEATHERIZATION ASSISTANCE PROGRAM STANDARDIZED CURRICULUM – December 2012. Learning Objectives. Base Load Measures. By attending this session participants will be able to: Define base load measures.
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Base Load Measures WEATHERIZATION ENERGY AUDITOR SINGLE FAMILY WEATHERIZATION ASSISTANCE PROGRAM STANDARDIZED CURRICULUM – December 2012
Learning Objectives Base Load Measures By attending this session participants will be able to: • Define base load measures. • Recognize base load measures allowable in the WAP based on Appendix A. • Discuss how to use utility bill analysis to determine base load usage. • Identify tools useful for calculating energy and money savings associated with common base load measures.
Base Load Defined Base Load Measures Base Load: The energy used by electric or gas appliances in a home that is not used for space conditioning, thus it is not a seasonal load. Typical measures include: • Lighting retrofits. • Refrigerator replacement. • Water heater modification. • Low-flow fixtures.
Why Target Electric Base Loads? Base Load Measures Percent of Total Energy Costs by End Use in Income Eligible Households Lighting 6% Refrigerator 9% 30% Space Heating Appliances 27%(other) …. 4% Cooking 15% Water Heating Space Cooling 9% Source: Energy Information Administration, U.S. Department of Energy
Why Target Electric Base Loads? Base Load Measures • About half of the electricity used by households with electric heat is for base loads. • Many homes heated with fossil fuel have higher annual electric bills than gas or oil bills. Photo courtesy of PG&E
Consumption Analysis Base Load Measures 1. Analyze Bill 2. Survey Site 3. Reconcile the Two #1 Photo courtesy of National Energy Deregulation Information #2 Photo courtesy of National Home inspection Services of New England #3 Photo courtesy of Life123 Inc.
Simple Bill Analysis Method Base Load Measures Bill Analysis • Review previous 12 months. • Average three lowest months. • Multiply by 12 to estimate annual base load usage. Photo courtesy of National Energy Deregulation Information
Site Survey Analysis Base Load Measures Site Survey Analysis • Account for typical consumption. • Where does all the juice go? • Build a consumption table based on: • Client interviews. • Known and guesstimated wattages. • Hint– Identify the 5 biggest users. Photo courtesy of National Home inspection Services of New England
Post-Survey Analysis Base Load Measures Post-Survey Analysis • Are there existing loads whose consumption can be reduced by: • Repair? • Installation or replacement? • Client education? • Is it cost effective? • Is it listed in Appendix A? Photo courtesy of Life123 Inc.
Bill Analysis Examples Base Load Measures • Record: • Lowest Reading • 2nd Lowest • 3rd Lowest • Average Monthly Base Load
Bill Analysis Example #1 Base Load Measures
Bill Analysis Example #1 Base Load Measures 442 522 538 1,502/3 = 501
Bill Analysis Example #1 Base Load Measures
Bill Analysis Example #1 Base Load Measures
Bill Analysis Example #2 Base Load Measures
Bill Analysis Example #2 Base Load Measures 255 262 312 829/3 = 276
Bill Analysis Example #2 Base Load Measures
Bill Analysis Example #3 Base Load Measures
Bill Analysis Example #3 Base Load Measures 695 752 888 2,335/3 = 778
Bill Analysis Example #3 Base Load Measures
Bill Analysis Example #3 Base Load Measures
What is High Usage? Base Load Measures • The greater the waste, the greater potential for savings. • Charts and table from experts, utilities, etc., seldom agree on exact kWh for average or high usage of various appliances.
Appliance Energy Use (Annual) Base Load Measures
(Very) General Rule of Thumb Base Load Measures There may be good potential for savings if a four-person household uses: • More than 600 kWh/month without an electric water heater, or • More than 1,000 kWh/month with an electric water heater.
Occupant Impacts Base Load Measures Base load use is affected by: • Number of occupants. • Size and efficiency of equipment. • Habits of occupants. Client education is key to effectively reducing base-load energy use.
Lighting Base Load Measures • Lighting accounts for up to 10% of total home energy use. • With Compact Fluorescent Lighting (CFL) retrofits, can cut that by 75%. • Overall energy reduction of 7.5% for the home.
Lumen Table Base Load Measures • CFLs save energy by producing more light (output) per watt of energy used. • The light output is measured in lumens.
Lighting Savings Table Base Load Measures • CFLs save energy by producing more light output (measured in lumens) per watt of energy used. * Annual Savings based on $0.11/kWh.
Lighting & CFL Considerations Base Load Measures • Dimmers • Photocells • Specialty bulbs (candelabra, reflectors, etc.) • Color Scale • CRI: 0 – 100; most CFLs are between 80-90 • Kelvin Temperature • 2700 - 3000K: Warm white/soft white light (incandescent) • 3500 - 4100K: Cool or bright white light • 5000 - 6500K: Natural or daylight • Mercury
Mercury? Base Load Measures • Most CFLs contain around 4 milligrams of mercury. • Reduced electricity use offsets the mercury in the bulb. The amount of mercury contained within a typical CFL compared to a US dime.
Refrigerator Replacement Base Load Measures • Replacement includes removal and decommissioning of old unit; must be included in cost for SIR calculations. • Only when cost-effective, SIR ≥ 1. • Based on metering or recognized database (AHAM, Home Energy, or Weatherization Refrigerator Guide). • Must meter at least 10% of units. Photo courtesy of US Department of Energy
Refrigerator Replacement Base Load Measures • Older models are typically energy hogs. • Worn gaskets make the unit run more often. • Insulation can be guessed by pushing on door. • Pushes in easily – likely fiberglass • Does not push in easily – likely solid foam • If Coppertone brown, avocado green, or harvest gold, replacements can be cost-effective. Photo courtesy of US Department of Energy
Michael Blasnik’s Refrigerator Study Base Load Measures • In NE, adding 11% to DOE rating is a fairly good predictor of actual use. • Other factors affect actual use: • Occupants: add 5% per person to rated use • Anti-sweat switch on: add 20% to rated use • Through-the-door ice service: add 15% to rated use • Visible gaps in door seal: add 15% to rated use • Refrigerator bought used: add 20% to rated use • Thermostat setting high: add 5% to rated use • Thermostat setting really high: add 10% to rated use • No relationship between rated and actual use for refrigerators located in basements.
Metering Base Load Measures • At least two hours • Disable defrost cycle for duration • Adjust for temperature variation Photo courtesy of US Department of Energy
Metering Duration ≥ 2 Hours Base Load Measures • Debate over how long a refrigerator must be metered to accurately estimate annual energy use • 1-hour tests accurate within ±10% only 18 times out of 100 • 3-hour tests increase ±10% accuracy to 90 times out of 100 • Currently recommending at least 2 hours
Defrost Cycles Base Load Measures • Defrost cycles during metering can significantly affect accuracy of results. • Demand of 380 watts or more usually indicates the defrost heaters are on. • If no defrost cycle during metering, add 8% to metering results.
Defrost Timers Base Load Measures Typical Timers Square / Rectangular Timers Figure Source: Refrigerator Guide
Defrost Timer Locations Base Load Measures Timer may be found in virtually the same locations in top- or bottom-freezer models or side-by-sides. May be under a small panel in the roof of the food compartment May be behind lighting panel Usually inside of a removable mounting box Timer may be located inside the FREEZER section of certain bottom-freezer models. Most common place is somewhere behind the kickplate. (Shown removed in this illustration.) You may need to lift or move a bundle of wires to see it. Figure Source: Refrigerator Guide
Advancing Defrost Timers Base Load Measures Use a broad-tipped screwdriver to advance past the defrost cycle for metering purposes. Remember to add 8% to metered results to account for regular defrost cycles. Defrost Cycle 1st Loud Click 2nd Loud Click Run Cycle Some timers have a defrost cycle every 180 degrees; in others, it’s every 360 degrees. Figure Source: Refrigerator Guide
Adjust for Temperature Variation Base Load Measures • Delta T between inside the refrigerator and ambient effects efficiency: 2.25% to 2.5% per °F. • To calculate correction factor, multiply the temperature difference by 2.5%. • If kitchen is cooler than normal during metering, add the correction. If warmer, subtract. For example, if the kitchen is normally 72°F, but the temperature is 66°F during metering: 1+ (2.5% x (72°F - 66°F)) = 1+ (0.025 x 6) = 1.15
Refrigerator Calculation Metered usage (kWh) Metering Duration (minutes) 0.882 x 60 minutes hour x 8,760 hours year Base Load Measures • If existing refrigerator is metered, assuming typical ambient temperature during metering, kWh/year = • 0.882 is a factor to adjust estimated energy usage since the crew asks the client not to open and close the refrigerator during metering. • Source: John Proctor
Can’t Always Meter Base Load Measures • It is not always possible to meter the refrigerator. • Cannot move fridge without damaging floor • Difficult access due to cabinets, furniture, stove, etc. • Receptacle suspect • When metering is not possible, use Association of Home Appliance Manufacturers (AHAM) database for energy use of existing refrigerators.
Adjust for Age Base Load Measures • Refrigerator efficiency degrades between 1% and 2% per year of operation. • NEAT tool accounts for this in audit. • When using database instead of metering, correct for age of appliance. NEAT Adjustments to AHAM Appliance Energy Data for Refrigerator Age
Control Settings Matter Base Load Measures Energy Use of a 15 ft3 Maytag Source: Larry Kinney, E Source, Boulder, CO, 2001
Other Refrigerators Issues Base Load Measures • Replacement refrigerators must comply with UL 250. • Must properly dispose replaced units per Clean Air Act 1990, section 608, as amended by 40 CFR 82, 5/14/93. • Cost of disposal, if any, should be reflected in SIR calculation.
Clean Refrigerator Coil Base Load Measures Even if replacement is not an option, some savings are possible. * Savings based on $0.11/kWh
Water Heating Base Load Measures • Assess condition of appliance. • Test draft of gas water heaters (more information in Combustion Appliances section). • Adjust set temperature. • Insulate tank and first 6 feet of pipes. • Replace. • Reduce hot water use.
Assess Condition Base Load Measures • Damaged? • Rusty or corroded? • Leaking? This unsheltered water heater is less than 6 months old. Photo courtesy of US Department of Energy
Adjust Set Temperature Base Load Measures • Mark original position of dial. • Verify water temperature. • Set back to 120F. • Adjust as needed. Photo courtesy of US Department of Energy
Reduce Setting from 140°F to 120°F Base Load Measures * Savings based on $0.11/kWh