As we are responsible for the Engineering Procurement and Construction (EPC) of the cogeneration plants, we can split up the scope in following main blocks.



Although it is not the mission of CALLENSVYNCKE to sell only studies, in many times we offer feasibility studies as a kind of business development.


A concept study is an essential part for the correct dimensioning of the CHP and can convince the customer of the feasibility of the project. However, main goal remains engineering and building of the plant!


Before contracting, we (always) thoroughly evaluate the different scenarios. CALLENSVYNCKE is strong in judging risks and balancing economical and technical advantages. Together with our customer, we discuss the results of the study and propose the optimal configuration. Once the customer agrees with the solution, we start with the engineering.


Based on the Process Flow Diagram (PFD), we prepare a Process and Instrument Diagram (P&ID).


This P&ID serves as the base for the further detailed engineering being functional description, control description, all kinds of lists (like equipment list, interface list, tie-inn list...) and drawings. In our 3D plant model, our design engineers fix the layout and check the pipe routings to avoid collisions which results in accurate isometric drawings, a plant layout, earthing plan, load plan...


As EPC contractor, we fully integrate the selected parts and technologies of our different subcontractors and partners.


If the available gas pressure in the gas distribution system is not sufficient for the specs of the gas turbine, we install a flexible gas compressor to boost up the gas pressure.


Often, the gas pressure in the local gas distribution system is too high, so that a reduction to the required inlet pressure of the gas turbine or gas motor, is mandatory.

This expansion is an endotherm process, leading to very cold gasses. In many cases, gas heating before the pressure reduction is a must. For bigger capacities, a pressure reducing turbine can also be feasible.


Dimensioning of a CHP starts at the thermal power demand of the plant. The gas turbine (GT) is the supplier of the heat that is required for the generation of minimum steam demand within the heat recovery steam generator (HRSG).

At the same time the GT generates electricity.

Selection of the optimal turbine in combination with the appropriate HRSG is core business of CALLENSVYNCKE.


When the thermal power demand of the plant is mainly hot water or a limited amount of steam, a gas engine can be the more favourable solution.

There are many differences between a gas engine and a gas turbine, and the choice can only be made after studying the basic thermal and electrical requirements.

Judging the best power generator asks for a tailored concept, fitting to the possibilities / demands of our customer.


The heat recovery steam generator (HRSG) is a flue gas heat recovering system, which produces steam.

The HRSG is designed to produce the minimum required steam load of the plant, with only the exhaust gas enthalpy of the turbine.

Variation on the thermal power requirement during production can be covered by a post-combustion system. This post combustion / secondary firing is possible, because there is a lot of oxygen left in the flue gasses from a gas turbine.

Depending on the required maximum steam demand and temperature/pressure profile, the HRSG can be executed as a water tube-, fire tube- or even combi-concept.


If electricity is the driver of the project, a steam turbine can be a suitable solution. A condensing steam turbine doubles almost the electrical efficiency.

Depending of the required steam profile, meaning the steam pressure steps and capacities, also a backpressure steam turbine, with one or more bleeds, can be installed.

This type of projects results typically in a tailor made solution, taking into account a lot of parameters, which is the core business of CALLENSVYNCKE.


If an industrial plant is working with steam, the installed cogeneration system is the basic steam supplier and thus the heart of the production process for energy saving reasons.

During maintenance periods of the turbine and/or HRSG, a back-up boiler is recommended. In such concept, we integrate the BUB in the same water/energy concept as the HRSG.

The BUB can be kept in hot standby to cover the steam peak demands that are above the maximum capacity of the HRSG.


The lifetime of a boiler is very much depending on the water quality that is fed into the boiler. The thickness of the tubes and shell is reducing during regular operation. But the speed of degradation is mainly depending on the quality of the water and the water treatment.

When a steam turbine is installed, the quality of the feed water must even be higher.

Depending of the installed technology, CALLENSVYNCKE, designs a tailor-made solution for the water treatment.


CALLENSVYNCKE takes care about correct integration of the generators into the MV-installation. This includes as well synchronization to the grid, step up transformer selection, protection arrangements, earthing concepts...

Starting from the grid-study till first injection on the grid, CALLENSVYNCKE is your partner.


Besides the selection of the prime movers and the heat recuperation part, there are still hundreds of components, supporting structures and parts for the connection, measuring and control of the whole installation. All these interconnecting piping, cabling, measuring and controlling devices,... in order to complete the CHP plant, are part of the ‘balance of plant'.


Already during the sales-phase a project manager is allocated to the project and is involved in the meetings. By this way, we guarantee a smooth transfer of accountability between the sales and project phase.

During the project realization, the project manager is the communication partner for all different suppliers, the customer, but also of our own allocated project team.

Project management is a point where we believe we make the difference with our competitors. Our personal, direct approach of the project manager and his team of specialists, is in all projects well appreciated by our customers, and saves money and time of our customers.


The installation and commissioning are always supervised by one of our experienced field engineers. He takes care of the timescale, the budget and manages the site activities. Quality control, health and safety checks and inspection of the work are his flagships. He is in direct contact with the subcontractors, with the project manager and for our customer, he is the daily communication partner on site.


Depending where the site is located, we work with own forces for the installation and commissioning, or we hire a local crew which is supervised and instructed by our field engineer.

In any case, all site related activities remain the full responsibility of CALLENSVYNCKE.
Typically during this phase, we foresee the training of the staff/end users, finalize the manual and complete the handover (documents).