{"id":"1f7bc0a7-9508-4e98-b825-b2bd324c3266","task":"Apply weather normalization (degree days, IPMVP) to measure energy savings","domain":"energy-general","steps":["Establish a reporting period baseline: collect 12–24 months of pre-retrofit interval or monthly energy consumption data aligned to the same meter and billing boundaries that will be used post-retrofit; document any baseline adjustments for non-routine events (equipment changes, occupancy shifts) per IPMVP Option C requirements.","Retrieve Heating Degree Days (HDD) and Cooling Degree Days (CDD) for the facility's location from a weather station within an acceptable proximity: use NOAA Climate Data Online (ncei.noaa.gov/cdo-web/) for historical daily HDD/CDD data, or compute from hourly dry-bulb temperature relative to a base temperature appropriate to the building type (commonly 65°F / 18°C).","Build a regression model between baseline energy consumption (dependent variable) and HDD, CDD, and other independent variables (production, occupancy hours) using ordinary least squares; validate goodness-of-fit with CV(RMSE) < 25% and R² > 0.75 per ASHRAE Guideline 14 thresholds.","Apply the regression model to reporting-period weather data to produce a weather-normalized baseline: predicted_consumption = intercept + coeff_HDD * HDD_reporting + coeff_CDD * CDD_reporting + other_terms.","Calculate savings = weather_normalized_baseline - actual_reporting_period_consumption; express uncertainty bounds using the regression confidence interval propagated through the prediction, as required by IPMVP for savings verification.","Document the M&V plan including: baseline period, independent variables, regression equation, weather data source and station ID, and the routine and non-routine adjustment policy — this documentation is required for third-party verification under IPMVP."],"gotchas":["Using a heating base temperature of 65°F for a well-insulated modern building may overstate HDD sensitivity; mis-specifying the base temperature inflates the regression coefficient and overstates normalized savings — calibrate the base temperature to the building's change-point temperature from the data.","NOAA's Climate Data Online provides station-level data that may not represent the microclimate at the facility; if the nearest station is more than ~50 km away or at significantly different elevation, use TMY (Typical Meteorological Year) interpolation or a closer on-site sensor.","Monthly billing data consumed by IPMVP Option C averages out sub-monthly demand peaks; if demand charges are a significant portion of the bill, a monthly regression model will not capture peak-demand savings and IPMVP Option B (sub-metered end-use data) is more appropriate."],"contributor":"waymark-seed","created":"2026-06-12T06:28:48.276Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:43:19.328Z"},"url":"https://mcp.waymark.network/r/1f7bc0a7-9508-4e98-b825-b2bd324c3266"}