Use Case
Heating, Ventilation and Air Conditioning
This guide explains how to use FlatPeak to reduce energy costs for Heat-Pumps, Air Conditioners (HVAC) and Water Heating systems by optimising operation based on electricity prices.
Without cost optimisation, energy use is 40 kWh costing €6.5. With cost/time optimisation, usage changes to 38 kWh, but cost drops to €3.78.
Design
To optimise the operation of a HVAC system by energy cost:
Once the customer completes the Connect flow, or if you imported their tariff:- Identify periods when the energy cost exceeds the daily average.
- Proactively extend temperature ahead of high-cost periods and
- Lower energy consumption during periods of higher cost until either the temperature reaches the maximum allowable tolerance or the cost decreases, whichever happens first.
To display energy cost:
- Log consumed energy to the meter records API under the IMPORT tariff and IMPORT direction.
- Report energy costs to the customer using cost calculate API and request energy cost for the IMPORT direction.
To display savings:
You must be able to simulate the typical energy usage profile of your system (not optimised by energy cost).
- Log simulated consumed energy to the meter records API under the IMPORT tariff and EXPORT direction.
- When you want to display energy saving:
- Call cost calculate API and request energy cost for IMPORT and EXPORT directions.
- Subtract IMPORT cost from EXPORT cost to get savings calculated here.
Implementation
Find high energy cost periods
Find high energy cost periods
To identify periods of high energy costs, call the slots-threshold API endpoint and request all periods over 24 hours when energy costs are at the top 25% (you may wish to adjust this based on your system’s capabilities). We recommend making this call periodically to create an operating schedule for the following 24 hours.
Find low energy cost periods
Find low energy cost periods
To identify periods of low energy costs, call the slots-threshold API endpoint and request all periods over 24 hours when energy costs are at the bottom 40% (you may wish to adjust this based on your system’s capabilities). We recommend making this call periodically to create an operating schedule for the following 24 hours.
Create cost-optimised schedule
Create cost-optimised schedule
Use the data obtained in the previous steps to program your system to minimise energy consumption during high cost periods identified in step 1 and restore energy use during lwo cost periods identified in step 2.Actions you may consider:
| Asset Type | High Cost | Low Cost |
|---|---|---|
| Space Heating / Heat-Pumps | Lower flow temperature Widen deadband range Lower set point temperature Turn off boost function Ensure correct weather compensation | Restore deadband range to normal Reset flow temperature Restore set point temperature Consider pre-heating before high cost periods |
| Air Conditioning | Increase refrigerant temperature Widen deadband range Raise set point temperature Turn off boost function | Restore deadband range to normal Reset refrigerant temperature Restore set point temperature Consider pre-cooling before high cost periods |
| Water Heating | Do not heat (ECO mode if must) Avoid automatically reheating after water use | Heat to target temperature Perform bacterial heating cycle (if due) |
Also consider “pre-cooling” or “pre-heating” before high cost periods to maximise savings
Meter energy use
Meter energy use
To calculate the cost of energy used, submit meter readings from your system to one of the API endpoints:
If your system logs meter records as intervals, call the submit-interval-meter-records API. You can also use this endpoint to import historical records.If your device is an EV charger, we recommend that you log records “tagged” by the charging session ID if you have it. Use the The API response will indicate that the submitted records have been processed successfully. You can submit up to 10,000 records at a time for a device or location.
session_reference_id parameter in the request. This will make it easy to report the cost per charging session later.Make sure that you use the
units parameter correctly: W represents the speed of transfer over the accounting period; WH represents the amount of energy transferred over that period.If your system can distinguish between energy sourced from the grid versus from local generation, such as solar, set
"tariff_rate": "LOCAL" when submitting the records. This will tell FlatPeak to account for this energy as “free” when calculating its cost.Display energy costs
Display energy costs
When you want to display the cost of energy the system uses, call calculate-energy-cost-by-time-interval API. Cost can be returned either unaggregated or pre-aggregated by day, month or year.