Spot Price Optimizer

The Spot Price Optimizer function block is used to activate a load in hours when the energy price is the lowest.

After a trigger the block will pick a number of hours, defined by 'Demand', within the next hours, defined by 'Period' and activate the output 'O'.

Alternatively the Outputs Very High, High, Low and Very Low can be used to activate/deactivate a load. For this usecase you can for example connect the day pulse to the trigger.

If the data on the Inputs +0 to +23 is provided by a virtual http input, the price is only used if it was updated within the current hour, therefore preventing the use of outdated prices.

By changing the Mode setting, it can be defined how the inputs work Relative: +0 - +23 or Absolute an input for each hour for the current day.

The Spot Price Optimizer can be used as a source for the export and import price in the Energy Flow Monitor. Both function blocks must be on the same Miniserver.

Table of Contents


Inputs

Abbreviation Summary Description Value Range
Off Off Pulse: Outputs are reset / switched off.
On: Block is locked.
Dominating input.
0/1
Tr Trigger Starts the automatic. The output O will be activated as often as defined by 'demand' within 'period'. 0/1
+0 to +23 Relative Mode: Price in the hour now +0 to +23 Price forecast for the hour now + offset This inputs are not available when using the Epex Spot mode.
Absolute Mode: Price in the hour 00:00 to 23:00 Price forecast for a specific hour This inputs are not available when using the Epex Spot mode.




Outputs

Abbreviation Summary Description Value Range
O Active Output Output will be activated at the hours with the lowest price after a trigger. 0/1
Cv Current Price
vHigh Very High The current price is Very High compared to the other hours. Limits will be recalculated after a trigger out of the forecast values available at that moment, but not more than 'Period' hours will be used.
Is also activated when the current price is above the value set in parameter Max.
0/1
High The current price is High compared to the other hours. Limits will be recalculated after a trigger out of the forecast values available at that moment, but not more than 'Period' hours will be used. 0/1
Low The current price is Low compared to the other hours. Limits will be recalculated after a trigger out of the forecast values available at that moment, but not more than 'Period' hours will be used. 0/1
vLow Very Low The current price is Very Low compared to the other hours. Limits will be recalculated after a trigger out of the forecast values available at that moment, but not more than 'Period' hours will be used. 0/1
Max Highest Price The maximum price within the available time period after a trigger.
Min Lowest Price The minimum price within the available time period after a trigger.
Avg Average Price The average price within the available time period after a trigger.
AC API Connector Intelligent API based connector.
API Commands
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Parameters

Abbreviation Summary Description Unit Value Range Default Value
Demand How often the output O should activate within the period after a Trigger. h 0...∞ 4
Period Time period after a trigger from which the block picks the hours with the lowest price where the output O will be activated. h 0...∞ 24
Max Fixed very high price If the current price is above this value the very High output will always activate. - 1




Properties

Summary Description Default Value
Mode Relative: Inputs provide the price relative to the current hour.
Absolute: Inputs provide the price for each hour of the day (00:00 to 23:00).
Epex Spot: The inputs for the hourly prices are hidden, as the data is obtained directly from EPEX SPOT.
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Price Calculation Use a formula to calculate the actual price you are paying. Ask your energy supplier for the formula. I1 = price from the inputs or the epex spot price (without tax) -




Programming example

In the properties window, the mode, the formula for price calculation, the number of active hours, as well as the period in which the cheapest times are determined, can be set.
Also, an individual very high energy price can be defined and the unit adjusted.

With http input or commands the hourly energy prices are transferred to the function block.

From the Loxone Library a suitable template can be imported.

In this example, a trigger pulse is used to determine the 4 cheapest hours of the next 12 hours and the heat pump is switched on in these hours.
If the energy price is above the calculated or set very high value, then the pump is blocked.


Epex Spot mode

With Epex Spot mode, energy prices are obtained directly from the European Power Exchange EPEX SPOT and do not need to be added via virtual inputs. The Miniserver must be registered for this.

Therefore, the Epex Spot mode is set in the settings and the relevant market area to receive the energy prices is selected. The inputs for the hourly prices are hidden.
The energy prices are provided excl. taxes in Euro per kWh (€/kWh). Exception: For Great Britain the price is supplied in Pounds per kWh.
The data is obtained daily at 13:00 - 14:00 (UTC) for the next day.

Due to legal restrictions of EPEX SPOT, we cannot provide access to the data. The statistics will only be displayed in a future version of the user interface.


Calculation of outputs

The range between the lowest and highest price is divided into 4 equal parts, according to which the outputs are switched.

Diff = (Max - Min) / 4
Limit1 = Min + Diff
Limit2 = Limit1 + Diff
Limit3 = Limit2 + Diff