
Alliance member: Wenerate Kft., Hungary
Client: Orac Slovakia S.R.O. (Plastics product manufacturing)
Country: Slovakia
Funding: self-financed
Duration: 08/2023 – 03/2024
Project description:
In this case study, we demonstrate how significant energy and cost savings can be achieved by implementing an advanced energy management system, using the example of an injection molding company with 150-199 employees and an annual revenue of more than 10 million Eur. Within a single year, the company was able to save €30,000 with the help of the Wenerate energy management system.
Injection molding machines are high-energy-consuming devices, with nominal power typically ranging between 20-110 kW, primarily determined by the injection volume among numerous factors. At the company’s site, a total of 21 sub-metering points have been established. Injection molding machines with a nominal power of less than 50 kW, as well as other equipment serving the site (e.g., compressors, pumps, fans, etc.), have also been equipped with sub-meters.
Services performed:
The Wenerate system enabled them to continuously monitor the energy consumption and performance of injection molding machines, as well as many other energy parameters. The implementation of the system allowed them to identify areas where they could improve efficiency and reduce energy usage, receive alerts for abnormal consumption values, and thus detect faulty machine operations.
The energy management system almost immediately informed the company that injection molding machines occasionally experienced phantom consumption due to being operated at non-optimal times or modes. For an injection molding machine with a nominal power of 80 kW, they were astonished to find that the device’s operational energy cost ranged between 15-24 EUR, given an electricity cost of 0.29 EUR/kWh. This translates to an operational cost of 0.25-0.4 EUR per minute. In the first week following the implementation of the energy management system, they detected 117 minutes of phantom consumption, meaning the machine was on without performing any production activities. Thus, for these 117 minutes, they paid €40 in excess electricity costs for just one injection molding machine. Extrapolating this to 50 weeks — a typical year for them — resulted in a potential savings of 2000 EUR for a single machine.
In addition to immediate energy savings, the Wenerate energy management system demonstrated several other advantages. The company was able to identify voltage-related anomalies because the system sends automatic alerts for under- and over-voltage conditions outside the tolerance range. Besides preventing machine failures, real-time voltage monitoring is crucial because sustained high values can lead to additional costs without affecting production efficiency.
For instance, if the 80 kW nominal electric power injection molding machine operates at 400V voltage and 125A current, assuming a power factor of 0.95, running at 5% higher voltage can result in an additional cost of 1-1.5 EUR per hour at an electricity cost of 0.29 EUR/kWh.
The sub-metering system they implemented differs from other market-available sub-metering systems in that its associated software allows measurements to be assigned to specific equipment types. This maximizes the potential of artificial intelligence (AI)-based analysis. Equipment-specific AI-based consumption analysis can identify consumption patterns indicating potential failures. The company benefited from this AI-supported analysis when the compressor measurements triggered an alert indicating it was operating for more hours and at higher performance than usual. A visual inspection revealed that the issue was caused by a clogged air filter and its improperly scheduled replacement. Immediate feedback and intervention resulted in significant savings for the company.
Regarding the specific return on investment of implementing and maintaining the Wenerate system, it was found to cost the company 22 EUR/measurement point/month, including installation, software usage, and support during the commitment period. In comparison, the savings achieved per measurement point amounted to 143 EUR/month, based on the factors discussed in the article for the specific site. This represents a very short payback period. The key to this is that, along with the implementation of the energy management system, the company’s employees and management must be committed to exploiting the energy-saving potential. The software can highlight a malfunction, excessive energy consumption, or specific waste, but without the company’s willingness to intervene, these insights remain unaddressed. Enhancing production efficiency and company profits is usually in everyone’s best interest, as annual bonuses or salary increases often rely on these metrics.
Cost reduction and profit increase tracking are often performed by the controlling or finance department. To facilitate their work, we created the Wenerate API, which allows data to be transferred to popular enterprise resource planning (ERP) systems such as SAP or Oracle. Additionally, if the production department also requires the data, the Wenerate API can be integrated into most manufacturing execution systems (MES).