Case studies
HVAC / Cold storage
This guide explains how to use FlatPeak to reduce energy costs for cold storage or HVAC systems by optimising operation based on electricity prices.
Without load shifting, energy usage is 96 kWh, resulting in a cost of $49. However, with load shifting, energy usage slightly increases to 98 kWh, but the cost decreases significantly to $34.
Design
To optimise the operation of a cold storage 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.
Create cost-optimised schedule
Create cost-optimised schedule
Use the data obtained in the previous step to program your system to lower the temperature to the minimum allowed before the higher-cost period begins.
In the below example, the high energy cost period is between 08:00 and 09:20. You will program your system to start lowering the temperature at 07:45 to reach the minimum allowed temperature of -21 before the higher cost period begins.
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.