Harvest Thermal - Measurement and Verification Plan
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Executive Summary
This document outlines the measurement and verification (M&V) methodology and data intake requirements for the electrification projects managed by Harvest Thermal. The plan encompasses baseline establishment, metering infrastructure, data collection protocols, and savings calculation methodologies.
Methodology Selection
We will use the Device-Level Sensors for Electrification methodology.
We expect to receive device-level reporting data and information about the legacy system.
Data Requirements
Incorporated Data Requirements
The following are defined in the Shared Guidelines methodology:
- Definitions
- Electricity Carbon Intensity Calculations
- Shared Data Intake Requirements
- Consequential Carbon Accounting Rules
- EAC Definition and Rules
- Generated Versus Avoided Emissions
User-Provided Data Requirements
The following is a static description of the required and optional fields for a given Asset. See the updated CSV template with the correct column names and timeseries description.
Attributional Data
The following data is required in addition to what is listed in Shared Guidelines methodology.
Building Data
| Name | Unit | Description |
|---|---|---|
| PodId | Asset id | |
| zip | Zipcode of system | |
| SystemType | Type of system: Open – 3rd Party Heat Pump and Air Handler Classic – Ecoer Heat Pump and Airscape Air Handler | |
| Storage | gal | Total storage capacity of hot water tanks |
| DateCommissioned | Date system was commissioned and became operational | |
| RatePlan | Name of utility rate plan | |
| Utility | Name of utility | |
| Baseline | Heating and hot water baseline before Harvest upgrade: Gas Electric resistance (ER) Single-speed HP + ER backup |
Intervention
| Field | Description | Default if not provided | Required? | Use |
|---|---|---|---|---|
| LegacyDhwUEF | Prior DHW efficiency (UEF) | 0.63 | - | Modeling |
| LegacySpaceHeatingEff | Prior space heating efficiency | 0.8 | - | Modeling |
| LegacySpaceHeatingEffUnit | Unit for legacy space heating efficiency. Options: HSPF, HSPF2, AFUE | - | - | Modeling |
| LegacyCoolingSEER2 | Legacy cooling SEER2; None if no legacy AC existed | None | - | Modeling |
| LegacySpaceHeatingSystem | Prior space heating system. Options: gas_furnace, electric_furnace, gas_boiler, electric_boiler, gas_combined, electric_resistance, electric_heat_pump_non_inverter, electric_heat_pump_with_inverter | - | - | Modeling |
| LegacyWaterHeatingSystem | Prior water heating system. Options: gas_tankless, electric_tankless, gas_storage, electric_resistance_storage, gas_combined, electric_heat_pump | - | - | Modeling |
Timeseries Data
| Name | Unit | Description |
|---|---|---|
| PodId | Asset id | |
| qDHW | BTU | Total energy delivered from Pod for domestic hot water: (temperature of water out of tank - temperature of cold water into tank) * flow of water into tank * conversion factor |
| qHeat | BTU | Total energy delivered to hydronic coil: (temperature of water to hydronic coil - temperature of water returned from coil) * flow of water circulating to coil * conversion factor |
| qHpacHeat | BTU | Modeled heating energy delivered to home by heat pump AC (HPAC), using the following calculation: qHpacHeat = (eHpacHeat+eFanHpacHeat) * HSPF2 / 3.412 |
| qHpacCool | BTU | Calculated cooling energy delivered to home by heat pump AC (HPAC), using the following calculation: qHpacCool = (eHpacCool+eFanHpacCool) * SEER2 / 3.412 |
| eHpwh | BTU | Electrical energy used by heat pump water heater to generate hot water |
| eBooster | BTU | Electrical energy used by electric booster (if applicable) |
| ePod | BTU | Electrical energy used by Pod electronics |
| eCirc | BTU | Electrical energy used by pod circulation pump for hydronic heating |
| eFanHydro | BTU | Electrical energy used by fan during hydronic heating |
| eHpacHeat | BTU | Electrical energy used by heat pump AC for heating |
| eFanHpacHeat | BTU | Electrical energy used by fan during HPAC heating |
| eHpacCool | BTU | Electrical energy used by heat pump AC for cooling |
| eFanHpacCool | BTU | Electrical energy used by fan during cooling |
| eFanOnly | BTU | Electrical energy used by fan when in fan mode |
| TaOut | °F | Average outside temperature over hour |
| CostLevel | LOW/HIGH | Low = charge thermal battery, High = discharge thermal battery. Cost levels are calculated by the Harvest Pod based on price and outdoor air temperature to optimize for operating costs. |
| Price | $/kWh | Electricity price |
Data Management/Auditing Agreements
Harvest Thermal will aggregate the minute-level data electricity into hourly, as well as calculate the heating and cooling outputs based on the minute-level temperature differentials (qDHW, qHeat, qHpacHeat, qHpacCool). All values will be in units of BTUs.
Harvest Thermal will supply the device telemetry data used in this analysis. The data will be made available through periodic CSV dumps into a private Google Drive folder.
Additional Counterfactuals to Measure Against
In addition to the legacy system, Harvest Thermal has requested additional “counterfactual” systems to measure against. These counterfactuals will not be used for EACs, but will be helpful as diagnostic and analytic tools.
Baseline System-COP Definition:
The baseline system is the counterfactual: the system Harvest is being compared to. This can be electric resistance, single-speed heat pump with electric resistance backup that typically activates at 35-40 F, and variable capacity heat pump with ER backup that activates at a much lower temperature. In addition we include a Harvest + ccASHP Aux setup where we can calculate the thermal battery charge/discharge and percent of heating coverage the thermal battery provides.
The Baseline system-COP is currently defined as a linear curve in 2 segments:
- Below Tswitch (programmed switchover temperature): COP is 0.95.
- Above Tswitch: COP is taken from HSPF2 data (see below for more detail on the use of HSPF2).
| Counterfactuals | T_switch (F) | Counterfactual System-COP |
|---|---|---|
| Electric Resistance | 35 | 0.95 |
| Single-speed HP + ER backup | 35 | 2.20 |
| Inverter-driven cold climate HP + ER backup | -10 | 2.48 |
| Harvest (No Load Shifting) | -10 | 2.89 |
| Harvest + ccASHP Aux (No Laod Shifting) | -10 | 2.48 |
Non-Harvest Baselines (ER, HP+ER Backup, Inverter-Driven CCHP+ER)
Load Reduction/Shift Baseline (kWh): This metric quantifies the electrical energy saved during each hour by utilizing a Harvest system with thermal storage instead of running electric resistance (ER) heating, a single stage heat pump or inverter-driven heat pump with ER backup and a switch-over temperature. It calculates the actual thermal consumption of the home by adding up the domestic hot water use, hydronic heating, and DX heat pump heating (converted to thermal energy using the S-COP derived from HSPF2 for DX Heat pump). This hourly thermal consumption of the home is then divided by the baseline system-COP (defined in the table above) to determine what an instantaneous electrical usage would be, and subtracts the actual electrical consumption of each hour of the Harvest system with thermal storage.
Harvest + Auxiliary ccASHP
Thermal Battery Charge/Discharge (kWh): This metric quantifies the electrical energy saved during each hour by utilizing thermal storage instead of running a heat pump with identical performance instantaneously. It compares the actual electrical consumption to a theoretical baseline where all heating demand would be met instantaneously without storage. The calculation divides the hydronic thermal energy provided that hour by the calculated hydronic S-COP to estimate what the electrical consumption would have been without storage, adds the DX heat pump electrical use (which can’t be load-shifted), and then subtracts the actual total electrical consumption during the hour. A positive value indicates successful load shifting—the system stored thermal energy during off-peak periods and is now drawing from storage instead of consuming electricity. A negative value means the system is actively charging storage, consuming more electricity than needed for immediate heating demands.
Percent Thermal Battery Coverage: This metric expresses the amount of heating that can be covered by just the thermal battery as a percentage of the total heating demand for each hour. It calculates the theoretical electrical input needed to meet the current thermal output (using S-COP for hydronic and the S-COP derived from HSPF2 for DX Heat pump, see below), compares this to the actual electrical consumption, and expresses the difference as a percentage. A value of 100% means complete load shifting—all heating is being delivered from storage with no heat pump operation. A value of 0% indicates no load shifting is occurring. Negative values represent “reverse load shifting” where the system is charging storage, consuming more electricity than the instantaneous heating demand requires. The calculation includes bounds to cap values between -100% and +100%, and returns special values when thermal demand is negligible.
Appendix
Hydronic System-COP Calculation:
The hydronic System-Coefficient of Performance (S-COP) measures heat pump efficiency when operating in hydronic mode, delivering heat via the water-based system for domestic hot water and space heating. This calculation captures all thermal losses, fan, pump, and controller energy use, as delivered heat is measured post-storage.
Thermal Energy Output: The numerator is the total useful thermal energy the hydronic system delivers for domestic hot water and space heating, covering all building demands. This includes thermal losses from storage and those associated with starting and stopping the heat pump’s water circulation.
Electrical Energy Input: The denominator includes all electrical energy used to produce and distribute hydronic thermal energy, encompassing defrost cycles, heat pump start/stop costs, circulator pump, controller electronics, and the air handler unit (AHU) fan when providing hydronic heating.
The S-COP is calculated by aggregating 14 or more days of thermal output and electrical input data for each Pod. This rolling window calculation smooths daily fluctuations, providing a stable metric per Pod and reveals performance trends as operating conditions or usage patterns change. Using a set of 100 Pods from January 2025 to July 2025, we find an average S-COP of 2.89 +- 0.479.
DX Heat Pump System-COP:
The DX Heat Pump S-COP estimates the real efficiency of an air-to-air heat pump, accounting for defrost, start-up, and AHU fan energy. Since Harvest cannot directly measure heat output, we use the field-determined average HSPF2 value of 8.7 from the Massachusetts and Connecticut Heat Pump Metering Study (MA22R51-B-HPMS) / (CT R2246). This aligns closely with the average manufacturer Region IV HSPF2 values for the heat pumps installed in that study. The study included 83 central heat pumps installed under MassSave or Energize CT programs that require variable capacity and other NEEP Cold Climate ASHP program requirements. The study’s sample is therefore made up of relatively high-efficiency heat pumps, representative of heat pumps likely to be installed with Harvest systems.
AHRI certificates for typical Harvest AHU and DX heat pump combinations yield a mean HSPF2 of 8.46 +- 0.74, which converts to an S-COP of 2.48 +- 0.22.