The tutorial shows different input options for CO2 allowance pricing variants. In particular, the last two variants demonstrate with nearly identical values the two input options in the scenario manager: Tabular input and Considering multiple simulation nodes.
The Reference case, in which a Heat Demand is covered by a gas Boiler and an Electricity Demand is covered by the Electricity Supplier, is compared with three variants, each of which is based on the same expansion with Photovoltaics and Heat Pump and which differ only in the development of the CO2 certificate price:
The method using support years is recommended if there are fixed price increases for certain periods that deviate from a percentage price increase. In addition, the scenario manager offers the advantage that a new operational optimization is carried out for each support year. This increases the simulation times, but the influence of the tabulated parameters on the optimal operation mode is taken into account.
The second expansion variant offers the advantage that the parameters can be changed directly in a table and no duplicated Simulation nodes are necessary. The influence on the operation mode is traceable in the Variant analysis, but not in detail (on time series level).
In the third expansion variant, the change in certificate prices is approximated by a price increase rate. The operation mode changes only marginally from year to year. In the five years, however, the effect adds up and is visible in the comparison of the years 2022 and 2026.
Reference Case
Variants With Photovoltaics and Heat Pump
In the variants, the Reference case is supplemented by a Photovoltaic system and a Heat Pump (see following figure).
Constant CO2 Certificate Price
The CO2 certificate price (to be entered in the Typical input data of the Fuel Tariff component, see following figure) is constant at 30 EUR/t in this variant.
The scenario manager is not used in this variant.
Tabular Specification of the Annual CO2 Certificate Prices
This variant contains only one Simulation node with a scheme that looks exactly like the previous variant. This variant differs from the previous one in that the scenario manager is used. Tabular input was chosen as the type of parameter input.
The Simulation node to be simulated has a start year of 2022. Additional support years are added: 2023, 2024, 2025, and 2026, for each of which a separate value for the CO2 allowance price (Price CO2 certificates) is specified in tabular form (see following figure):
Varying CO2 Certificate Price in Two Simulation Nodes
The last variant shows how expansion scenarios can be evaluated by considering different Simulation nodes in the scenario manager. For this purpose, in addition to the first Simulation node, another Simulation node is added for the support year 2026 (see following figure).
The schemes of both Simulation nodes are identical to those of the two previous variants. The difference lies in the parameterization. The following figure shows the Fuel Tariff from the first Simulation node of the variant.
An annual price increase rate (Inflation rate) of 20 % has been entered here. For the second Simulation node, the increased price of 60 EUR must be specified. The following figure shows the Fuel Tariff from the second Simulation node of the variant.
The increase in the CO2 certificate price means that the fuel is more expensive in 2026 than in 2022. The operating cost optimization therefore results in a slightly different operation mode. In 2026, it is often cheaper to cover the Heat demand with the Heat Pump instead of the Boiler (see following figure).
Results in the Variant Comparison
The small differences in the operation mode are also reflected in the energy balance form. Overall, the rising certificate prices mean that the Hot Water Boiler runs less in variants 2 and 3 than in variant 1.
The mode of operation from 2026 is identical in variants 2 and 3. The difference between variant 2 and variant 3 is the result of calculating a cost optimum for each year in variant 2 for the years 2022 to 2026. In variant 3, only the operating cost optima for the years 2022 and 2026 are taken into account.
The impact on energy costs for electricity and fuel over the years 2022 to 2026 can be seen in a bit more detail in the variant comparison Excel Export.
