Cogeneration solution for pharmaceutical energy efficiency, ensuring compliance and reliability.
April 24, 2025
Cogeneration, or Combined Heat and Power (CHP), is a technical solution that enables the combined generation of electricity and heat from a single energy source. This technology can lead to up to 30% primary energy savings compared to separate electricity and heat production. High-efficiency cogeneration plants, as defined by Directive 2004/8/EC, can benefit from the Energy Efficiency Certificate incentive system.
The high energy efficiency and access to incentives make cogeneration a particularly advantageous choice for energy-intensive companies, like this pharmaceutical client in Tuscany. To cover their electrical needs and produce thermal energy for their production processes, this client required a cogeneration plant.
Integrated cogeneration solution: energy optimization and maximum thermal recovery
To meet this need, we collaborated with Co.stell S.r.l., a leading cogeneration company, as the EPC contractor. Co.stell’s analysis of the plant’s electrical and thermal requirements found the ideal solution. This outcome, an optimized energy model, is based on an internal combustion engine, approximately 4300 kWel, that is integrated with a steam generator for recovery and an absorption plant for refrigeration.
Specifically, our team proposed a technical solution for:
- Maximizing thermal recovery on the cogenerator
- Providing a high degree of maintainability for the recovery generator
- Ensuring a safe PLC control system
The supply includes a recovery steam generator body for outdoor installation and side-mounted economizer for preheating generator feedwater and producing up to 3200 kg/h of steam. To maximize energy recovery, a dedicated economizer for water jackets was sized with a recovery power rating exceeding 360 kW and equipped with fin pitches to prevent contamination from oil condensation. As this client specifically requested, the economizer can be extracted from the front of the generator.
Safety and maintainability take priority: advanced technology for reliable operation
Safety/maintainability is a key strength of our solution: to address issues with the confined space, both the high- and low-temperature cogenerator exhaust casings are equipped with hinged doors for maximum inspectability. The generator features a pair of PSVs (2 x 100%) mounted on a changeover valve to minimize plant downtime. Last, the generator control system is based on a Siemens S7-1500 Fail-Safe with conductor exemption for up to 72 hours; the PLC can manage the steam generator’s main regulation and safety loops as well as the water jacket economizer’s safety and regulation.
Our solution, proposed and installed by Co.stell, has successfully met the energy model requirements and the end client’s high safety standards.
