A Local Heat Exchange Network (LHEN) allows different facilities inside a company to exchange heat or cold using heat pumps. The LHEN has a temperature that is more or less in the middle between the cold and the heat requirements.


LHENs are only interesting if more facilities producing cold or heat are interconnected. If it is an application with just one heat source that heats offices and a closed circuit cooler to avoid overheating during the summer, the LHEN does not bring any cost reduction.


A Shared Heat Exchange Networks (SHEN) allows heat and cold exchange with other companies. This makes it possible to forward extra heat during the winter, or to get extra heat during the winter and the summer. This is some kind of urban heating using low temperature water. It means that each connected facility needs a heat pump to get the water at the needed temperature.


I came to the idea of the LHEN/SHEN concept when thinking at improving the efficiency of a building containing an IT Room and Offices.


It looks like the main problem would be that urban heating work with big temperature difference, like 40°C-80°F between the water coming in and going out. This is done in order to move a lot of energy without moving too much water. This might be the main problem of this solution because heat pumps loose efficiency when the temperature difference increases.


To learn more about the concept and its costs, please check the documents below.


Please use the contact form if you have any comment.


Shared Heat Exchange Network
General concept
Shared Heat Exchange Network20131127.pdf
Adobe Acrobat Dokument 123.0 KB
Marginal costs diagram for LHEN/SHEN and for Cogeneration
Cogeneration being the main alternative to the LHEN/SHEN concept in urban heating, I wanted to compare the marginal costs. I don't have enough information to provide more than marginal costs.
Calculations are in the cost study (document in french at the bottom of this page).
Adobe Acrobat Dokument 38.5 KB

Et pour les francophones...

Chauffage urbain basse température
Un résumé sur 1,5 pages.
Chauffage urbain basse température.pdf
Adobe Acrobat Dokument 74.2 KB
De la difficulté de récupérer la chaleur industrielle pour du chauffage urbain
Un peu plus d'informations pour ceux qui veulent des détails.
Récupération chaleur industrielle20131
Adobe Acrobat Dokument 212.5 KB
Cost Study for LHEN-SHEN
All the values for the LHEN and SHEN that are in the marginal costs diagram are calculated in this document.
The document is in French.
Les calculs dont le résultat se trouve dans le diagramme des coûts marginaux (diagramme en anglais).
Adobe Acrobat Dokument 171.2 KB