For its new heat production, the Saint-Luc hospital in Sint-Lambrechts-Woluwe chose in 2021 to collaborate with Luminus Solutions, who developed a tailor-made solution. Three CHPs in a row, with a capacity of 1,200 kWe per machine, provide an overall energy efficiency of 88% and CO2 savings of 21% compared to separate production of heat and electricity.
Luminus Solutions’ approach is always flexible and tailor-made: every CHP project starts with proper dimensioning for optimum efficiency.
Therefore, a configuration with three independent 1200kWe engines was chosen instead of one or two machines of higher power. This increases flexibility and maximises plant availability: the engines can be shut down individually for maintenance and if one of the engines fails, the other two can still largely meet the heat demand.
Integration in the existing boiler house: a challenge with some obstacles
The new installation was fully integrated into the existing boiler house and feeds the local heat network. Integrating a new installation into an older one usually has its hurdles.
Indeed, during the preliminary study, it emerged that the existing subsoil of the boiler room did not offer sufficient stability for the new CHPs, and also the steel structure of the roof provided for the drycoolers, was not sturdy enough to support them. Therefore, Luminus Solutions chose to pour a new concrete floor and the drycoolers were given a new location on the roof of the medical archive. There, they are less visible and also cause less noise pollution.
A heat buffer was also installed next to the plant to capture excess heat. This can then be used at times of peak load, such as in the morning or evening. All electrical works and integration into the client’s high-voltage installation were carried out with care.
For a unique insight into the project, the entire construction of the installation was filmed with a timelapse camera and drone:
Luminus Solutions also provides omnium maintenance of the installation with its own technicians close to the site. This allows for rapid intervention in the event of problems, both on site and remotely. Indeed, Luminus Solutions can also monitor and manage the CHP through its online monitoring system, ensuring high availability and efficiency of the CHP.
Why fossil fuel CHP still helps reduce CO2 emissions
Even though fossil cogeneration does not seem ideal from an energy transition perspective – after all, you burn gas to make electricity, resulting in a direct negative impact on CO2 emissions – there are arguments in favour of CHP.
Indeed, Luminus Solutions’ motivation to install quality CHPs is exactly the opposite, as it reduces overall CO2 emissions compared to the separate production of electricity and heat.
That is why it is important to look at all levels of the carbon footprint: not just scope 1 because then, as a company, you only look at your own CO2 emissions. In that case, you will therefore consume more natural gas and emit more CO2. On the other hand, if you also take into account the (lower) purchase of electricity (scope 2), emissions will decrease. After all, simultaneous generation of heat and electricity is more efficient than producing them separately.