Introduction to EnergyPLAN
The main purpose of the EnergyPLAN model is to analyse the energy, environmental, and economic impact of various energy strategies. The key objective is to model a variety of options so that they can be compared with one another, rather than model one ‘optimum’ solution based on defined pre-conditions. Using this methodology, it is possible to illustrate a palette of options for the energy system, rather than one core solution. This could classify EnergyPLAN as a ‘simulation’ tool rather than an optimisation tool, even though there is some optimisation within the model.

Furthermore, the aim of EnergyPLAN is to model the ‘finishing point’ of the energy system rather than the starting point. The focus is placed on the future energy system and how that will operate, rather than on today’s energy system. Therefore, EnergyPLAN includes relatively detailed modelling of future technologies such as biomass gasification and synthetic fuels, but relatively aggregated modelling of today’s technologies such as power plants. The focus is on the future rather than the present.

EnergyPLAN is a deterministic model which optimises the operation of a given energy system on the basis of inputs and outputs defined by the user. Below you will find some examples of how to use EnergyPLAN. You can also read our short brochure about Smart Energy Systems here.

User-friendly tab sheet model

The EnergyPLAN model has been developed and expanded on a continuous basis since 1999. It is a user-friendly tool designed in a series of tab sheets and programmed in Delphi Pascal. Input is defined by the user in terms of technologies and cost specifications.

Design of energy planning strategies

The main purpose of the model is to assist the design of national or regional energy planning strategies on the basis of technical and economic analyses of the consequences of implementing different energy systems and investments. The model encompasses the whole national or regional energy system including heat and electricity supplies as well as the transport and industrial sectors.

Deterministic input/output model

The model is a deterministic input/output model. General inputs are demands, renewable energy sources, energy station capacities, costs and a number of optional different regulation strategies emphasising import/export and excess electricity production. Outputs are energy balances and resulting annual productions, fuel consumption, import/export of electricity, and total costs including income from the exchange of electricity.

EnergyPLAN compared to other models

Compared to other similar models, the following characteristics of EnergyPLAN can be highlighted:

    • EnergyPLAN is a deterministic model as opposed to a stochastic model or models using Monte Carlo methods. With the same input, it will always come to the same results. However, as we shall see in Chapter 5, the model can perform a calculation on the basis of RES data of a stochastic and intermittent nature and still provide system results that are valid for future RES data inputs.
    • EnergyPLAN is an hour-simulation model as opposed to a model based on aggregated annual demands and production. Consequently, the model can analyze the influence of fluctuating RES on the system as well as weekly and seasonal differences in electricity and heat demands and water inputs to large hydropower systems.
    • EnergyPLAN is aggregated in its system description as opposed to models in which each individual station and component is described. For example, in EnergyPLAN, the district heating systems are aggregated and defined as three principal groups.
    • EnergyPLAN optimizes the operation of a given system as opposed to models that optimize investments in the system. However, by analyzing different systems (investments), the model can be used for identifying feasible investments, as we shall see in Chapters 5 and 6.
    • EnergyPLAN provides a choice between different regulation strategies for a given system as opposed to models into which a specific institutional framework (such as the Nord Pool electricity market) is incorporated.
    • EnergyPLAN analyzes 1 year in steps of 1 hour as opposed to scenario models analyzing a series of years. However, several analyses each covering 1 year may of course be combined into scenarios.
    • EnergyPLAN is based on analytical programming as opposed to iterations, dynamic programming, or advanced mathematical tools. This makes the calculations direct and the model very fast when performing calculations. In the programming, any procedures that would increase the calculation time have been avoided, and the computation of 1 year requires only a few seconds on a normal computer, even in the case of complicated national energy systems.
    • EnergyPLAN includes hourly analyses of the complete smart energy system, i.e., district heating and cooling as well as electricity and gas grids and infrastructures, as opposed to models which have a sole focus on, for instance, the electricity sector.

Examples on how the model is used:

Example: Excess Electricity Production from CHP and Wind Power

Today, the share of wind power in Denmark is 20 per cent and the share of CHP corresponds to 50 per cent of the electricity demand. The EnergyPLAN model can be used to analyse the consequences of increasing the share of wind power.

  1. Question

    How high will the excess electricity production be, if the share of wind power is increased to 40 per cent?Answer
    The EnergyPLAN model calculates the electricity demand and productions hour by hour and identifies the annual excess production. See the diagram.

  2. Question

    What is the value of the excess production on the international electricity market?Answer
    The EnergyPLAN model calculates hour by hour the value on the Nord Pool market using 2006 prices and taking into account price-elasticities and bottlenecks. See the diagram.

Example: National Energy Policies and Strategies

In 2006, the Danish Association of Engineers proposed an energy strategy for Denmark 2030 with the objectives of increasing energy security, decreasing CO2 emissions and creating industrial development. The EnergyPLAN model was used for the overall analyses.

  1. Question

    How will the primary energy supply be effected by the proposal?Answer
    The EnergyPLAN model calculates hour by hour the energy balances taking into account fluctuations in demands and renewable energy sources. See the diagram.

  2. Question

    How will CO2 emissions be affected by the proposal? Answer
    The EnergyPLAN model calculates hour by hour the energy balances taking into account fluctuations in demands and renewable energy sources. See the diagram.
  3. Question
    The IDA 2030 proposal was composed by a number of individual measures. Which of them contributed best to the overall feasibility?Answer

    The EnergyPLAN model calculates the total costs of the reference energy system and the IDA 2030 energy strategy with and without each of the individual measures and thereby identifies the contribution to feasibility of each proposal. See the diagram below.