Energy consumption and costs have been recorded at the university for years. Over the course of time, this recording was implemented in more and more detail and automated and then analyzed. From this data, potential energy savings are identified and the success of implemented measures is reported. An annual energy and resource report has been prepared and published for several years. The current report can here be downloaded.
energy management
The energy management system at THM was designed to record the consumption of each individual building. This should by no means be taken for granted. Properties are often only recorded via the energy supplier's billing meters. For example, until about six years ago, there was only one district heating meter for several buildings on Campus A in Giessen . Nowadays, each THM building is recorded individually, unless the buildings are so closely intertwined that individual metering is not possible. This is the case, for example, in Friedberg with building sections A1-A4. Strictly speaking, these are not several buildings, but one building that has been continuously expanded over the course of its lifetime.
A meter matrix has been created for all properties to show the energy flow. Below, using Friedberg as an example, you can see that natural gas is supplied from the left side (yellow) - converted into heat by the boiler system or combined heat and power plant - and conveyed to the corresponding buildings.
(click image to enlarge)
The dependencies of the counters, for example main counters and secondary counters, can now be entered in the energy management software. In Friedberg, the annual efficiency of heat generation can be determined and continuously monitored. The losses over the distribution grid can be clearly determined. Individual buildings can be compared with each other. For this purpose, specific consumptions, eg kWh/m², are formed.
The meters are mostly recorded automatically and enable consumption to be displayed on a quarter-hourly basis. Based on this detailed breakdown, the consumption profiles of the buildings can be presented and analyzed very precisely. This information is used, among other things, to determine potential energy savings or to check the profitability of photovoltaic systems in detail. In 2018, for example, the high electrical base load consumption in the A10 was noticed. The ventilation technology was then optimized and the running times adjusted to the usage.
The hourly consumption can be compared with the potential yield of a PV system and the self-consumption of the self-generated electricity can be estimated very well.
As the graphic below shows, the success achieved through the use of such software can also be illustrated very well. Due to the new photovoltaic system on the A5, significantly less electrical energy had to be obtained from the energy supplier during the daytime hours than in the previous year (pillars with a gray background), since part of the requirement could be covered by the company itself. (click image to enlarge)
Another major advantage of energy management software is the timely detection of excess consumption. Because conspicuous consumption profiles generate a warning message so that the cause can be investigated and remedial action can be taken quickly.
