Factories continue to consume power even during a production shutdown period for a number of reasons: keeping cold rooms refrigerated, or compressed air under pressure, frost protection heating, etc. Even though limited, the residual baseload power demand can ultimately become expensive for an industrial site, hence the benefit of finding ways to reduce this baseload power demand. Below is an overview of possible solutions.
Traditionally in industries, the baseload power demand (called “heel” in French) may be defined as the “energy consumption level of a workshop during off-production periods”. This would obviously be the case at night, on weekends, during annual leaves, extended weekends or maintenance shutdowns, over longer or shorter time periods. The baseload power demand also varies depending on the season. For instance, standby power consumption during Christmas holidays will be higher than in summertime since the heating system continues to run to keep buildings and facilities from freezing.
Prior to implementing any actions, it is essential to estimate the minimum power consumption during production shutdowns. This baseload demand benchmark may be measured for instance during shutdowns between Christmas and New Year (for the winter baseload benchmark) and during a long weekend in May (for the summer baseload benchmark). The maintenance crews always make special efforts to switch off all energy-consuming equipment components that should be shut down during both of these extended time periods. The remaining pieces of equipment will continue to run but at a minimum predefined level. Based on these data, managers can then encourage their teams to reach this baseload benchmark, with the help of a supervision interface to monitor the performance in order to improve the results of the workshops that are most distant from the benchmark, or conversely to recognize the results of those closest to the target. The manager is then able to prioritize the control checks and detect any faulty equipment. These fact-based data are helpful to promote the improvement process with the staff and ensure that the baseload consumption level during the next shutdown will be closer to the benchmark. Actions implemented to reduce the baseload demand can also involve equipment regulation (e.g. heating system control).
3. The “other” baseload demand
In addition to production shutdowns, there is also a fixed baseload demand when the factory is in operation, which is the sum of power consumptions of various natures. It may involve an operational mode in a workshop where all machines are running simultaneously even when unnecessary. It may also result from various latent “losses” such as leakage, thermal defects or faulty sealing in pressurized equipment. This “operational baseload” can be usefully reduced since it amounts to a continuous power consumption, and not just during production shutdowns which are actually relatively infrequent in a factory. In order to reduce this particular baseload demand, the power consumption of the workshop should first be measured during a dry run, per machine and per type of energy. These consumptions should then be analyzed to distinguish between normal demand and demand resulting from needless losses.