Heat recovery solutions drive decarbonisation at Irish pharmaceutical site

NIRAS's multi-year engagement with a leading pharmaceutical manufacturer in Ireland demonstrates how systematic energy analysis can unlock significant decarbonisation opportunities while working toward the client's ambitious target of 44% carbon reduction by 2030, using 2021 emissions as the baseline. 

Comprehensive assessment identifies 44 energy opportunities 

The project began in 2022 with a comprehensive Energy Efficient Design (EED) assessment following I.S.399 standards across four pharmaceutical manufacturing sites in Ireland. NIRAS conducted detailed energy balance studies and challenge sessions with the client, ultimately identifying numerous distinct energy-saving opportunities. The consultancy calculated potential savings to determine optimal carbon reduction options within the client's budget parameters. The opportunities in each plant were short-listed for highest impact and alignment to strategic goals.  

Heat pump technology replaces steam systems 

The primary focus centered on replacing conventional steam-to-hot-water heating systems with heat pump technology utilising waste heat recovery from the three process chillers' cooling water circuits. This transition from high-energy steam systems to low-pressure hot water heating represents a fundamental shift in how pharmaceutical facilities approach HVAC heating and re-heating post dehumidification. 

The site operates over 50 air handlers with heating coils requiring low-pressure hot water between 70°C and 80°C. Following NIRAS's recommendations, operational temperatures were optimised to 70°C supply and 60°C return, enabling the installation of a heat pump system capable of generating 100% of the LPHW heating load. This approach reduces the site's thermal load by 52%, releasing boiler capacity for process heating applications. 

From grant success to implementation support 

Following the initial study completion in early 2023, NIRAS supported the client's EXEED Stage 2 grant application process, securing a grant covering approximately 20-25% of the project costs. The consultancy subsequently took on the role of subject matter expert for the project, providing detailed mechanical and electrical design services up to the vendor boundary point. 

The challenge intensified when the facility expanded operations while maintaining the same carbon emission cap established from previous baseline figures. While the initial heat pump project was designed to achieve the full 2030 decarbonisation target, increased production volumes now require additional measures to meet the 44% reduction goal. 

Building perspective 

This project illustrates how pharmaceutical manufacturing can adapt to increasingly stringent environmental regulations without compromising operational requirements. The heat recovery approach addresses a critical industry challenge: maintaining precise temperature control for sensitive processes while reducing energy consumption. 

Dual-loop system maximises efficiency 

The solution's design maximises equipment utilisation throughout operational cycles. During summer months, when HVAC heating demands decrease, spare heat pump capacity redirects to water heating applications, ensuring year-round efficiency gains. 

To address hydraulic constraints and maximise system flexibility, NIRAS provided a concept design for a second LPHW loop operating between 65°C and 55°C, connected to the existing system through heat exchangers. This secondary loop accommodates additional applications including soft water heating to 21°C and preheating soft water supply for Water for Injection (WFI) and clean steam generation columns—processes currently dependent on steam heating. Future air-to-water heat pumps can connect to this new loop to provide additional capacity during peak demand periods. 

The comprehensive approach includes complementary improvements in boiler control systems, enhanced metering capabilities, and potential steam accumulators to reduce peak load demands. NIRAS currently provides ongoing engineering support during the detailed engineering phase of the heat pump implementation. 

A method to copy 

The project demonstrates how systematic energy analysis combined with proven heat recovery technologies can help pharmaceutical facilities meet expanding production requirements within existing carbon budgets. By focusing on waste heat utilisation rather than additional energy inputs, the solution aligns operational needs with environmental objectives. 

The multi-phase approach – from initial assessment through detailed design and implementation support – provides a framework other pharmaceutical manufacturers can adapt to their specific operational contexts and regulatory requirements.