Conversion Technologies

Conversion Technologies are systems that transform one or more Energy Carriers into different types (e.g., a gas boiler converting natural gas to heat). Each technology is defined by:

• Technical Parameters: Efficiencies and technical limits.

• Financial & Environmental Parameters: Investment costs (CAPEX), operational costs (OPEX), and embodied emissions.

For parameters, see the Conversion Technology Parameters section

Technology Modes

A Mode represents a specific operational "regime" with its own set of inputs, outputs, and efficiencies. A single technology can have multiple modes to reflect different seasonal or functional behaviors.

• Example: A reversible heat pump has a Heating Mode and a Cooling Mode, each with a distinct Coefficient of Performance (COP).

• Configuration: Technical parameters are applied at the Mode level to allow for this granular operational modeling.

Primary vs. Non-Primary Modes

To ensure costs accurately reflect physical hardware requirements, modes are categorized:

• Primary Mode: Modes for which the sizing must be reflected in the cost and CO2 emissions. The technology's costs are derived from the capacity requirements of these modes.

• Non-primary mode: These serve as "bonus" modes. Their capacity does not increase the technology's investment or operational costs, nor CO2 emissions, representing secondary use of existing hardware.

Mode Capacity

The capacity of a specific mode is the maximum hourly sum of all primary outputs recorded for that mode.

Users can choose between two sizing behaviors:

• Choose “Optimize” mode capacity: Optionally enter minimum and/or maximum installed capacity; the optimal capacity is selected within this range. If a minimum capacity is specified and the default option is selected, then the Installed Capacity can be 0 or greater than the minimum.

• Choose to “Specify” mode capacity: Installed Capacity is held at a fixed value. Operating capacity (which does not influence investment costs) may be equal to or lower than Installed Capacity.

Technology Capacity

The Technology Capacity represents the installed capacity of the unit and is used for cost and CO2 calculations. It equals the maximum total primary output summed across all primary modes at any single point in time.

Example Calculation

• Mode A peak (Primary): 100 kW at Hour 5.

• Mode B peak (Primary): Peak of 200 kW at Hour 10.

• Peak of the sum of primary modes: At Hour 8, Mode A and B produce a combined 250 kW.

Result: The Technology Capacity is 250 kW

Mode Efficiency

The efficiency of a mode indicates energy dissipation within systems. The sum of output efficiencies represents the mode's total efficiency. Specifically:

• A total efficiency of 100% means useful energy is conserved within the system.

• A total efficiency below 100% indicates useful energy is lost in the system. For example, heat-losses happen in the technology, and is not modeled as a “waste-heat” flow.

• A total efficiency above 100% indicates useful energy is created within the system. For example, useful heat is extracted from the environment and is not modeled as a “ambiant air” flow.

Example Heat pump

The efficiency of a standard input (with two inputs) is set as follow:

The calculation is the following:

Output EC_i = Sum of Inputs * Efficiency Output_i

HT Heat = (100 + 200) * 100% = 300

In this case, 100 units of Electricity and 200 units of Ambient Heat will lead to 300 units of HT Heat. This refers to a yearly COP of 3.

In the App, the numbers are entered as follow:

Example Chiller

For chillers, there are two ways to model Cooling Energy. The first method assumes Cooling Energy as a service, meaning the energy is generated and supplied. For example, when modeling a chiller with an Energy Efficiency Ratio (EER) of 2, the process would be as follows:

This means that an input of 100 units of electricity will result in the generation of 200 units of cooling (based on an EER of 2) and 300 units of heating (assuming the electricity is fully dissipated as heat).

100 units electricity would give in this case 300 units of HT Heat and 200 units of Cooling. From which a EER of 2 is calculated. In this case, the cumulated output efficiency is larger than 100%, which hints at the ‘creation’ of energy. This is the case because it is considered that Cooling Energy is an additional service.

In the App, the numbers are entered as follow:

Alternative Method Chiller

However, there is an alternative method where Cooling Energy is treated as an extraction of energy demand. To use this method, you should set the Cooling Demand to "reversed." In this case, the chiller can be modeled as a heat pump with an EER of 2 (or COP of 3).

In the App, the numbers are entered as follow:

For this method, it is crucial that the box ‘reverse’ in the step Energy Demands is ticked for the Cooling demands, as doing so will consider cooling as an extraction of heat.

Simultaneously of Operation

Different modes can operate simultaneously. To prevent this, leave the “simultaneous” tick box unchecked, indicating the mode cannot run with others. This may increase optimization time.

Alternatively, a less computationally intensive option is defining a different Seasonal or Hourly Operation for each mode.

Seasonal and Hourly Parameters

It is possible to enter Time Varying efficiencies, either monthly or hourly values. To do so, select Time Varying instead of Fixed for the Output EC Efficiency.

The case of heat pumps

In the case of Heat pumps, if you wish to apply a time varying COP, you will have to modify the Input EC Share and not the Output Efficiency. Indeed, it is the Input EC Share which defines the COP (= Heat HT/Electricity). See the example below: