**Abstract**

The paper presents an approach to the development of a heat and power model of industrial power plants. This algorithm is based on dynamic programming and modified sequential equivalence methods. The combination of the proposed methods is distinguished by the possibility of constructing models in a tabular form taking into account constraints in the form of equalities and inequalities. In addition, models can have points of discontinuities. The main criterion for optimization is the minimum of total costs for the primary energy carrier taking into account the costs of in-house needs and the wages fund. When constructing an equivalent model, technical and economic models of boiler units are used as initial data, which represent the dependence of the boiler steam output on the prime cost of live steam taking into account the fuel consumption for the production of 1 ton of live steam and possible volumes of energy resources in the fuel mixture of the boiler (for example, a mixture of blast furnace and natural gases). The equivalent model allows for the required steam capacity (taking into account the heating and production withdrawals) of the power plant to determine the optimal load of the boilers in terms of thermal power and, corresponding to them, the primary fuel consumption, as well as the costs of it. When constructing the model, the operational characteristics of the boilers are taken into account, namely, the temperature of the feed water and the steam pressure in the drum. A distinctive feature of the thermal power plant model is the consideration of all possible fuel ratios when searching for the optimal value of the power plant steam capacity. The developed algorithm is implemented in the original KATRAN-OptHeatPower software product intended for planning and making operational decisions in the management of normal, repair and post-emergency modes of industrial thermal power plants.

**Keywords**

Technical and economic model, energy boiler, energy resource, turbine generator, local power plant, power supply system, industrial plant.

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