Problem

A chain store with 58 branches was paying penalty fee on their electricity bills for excessive reactive power consumption.

Diagnosis

Loads were distributed unevenly between phases, current transformer selection was wrong, capacitor selection was wrong, power factor controller were not properly functioning.

Solution

58 Power Factor Controller, 58 Gateways devices and Monitoring Software were used.

It was determined that the electricity bill of a branch in a shopping mall was calculated with 10% addition for transformer losses. By installing Power Factor Controller, the penalty for excessive reactive power consumption and the 10% addition for transformer losses were avoided, thereby saving the store €8.850 per month.

No technical errors were encountered in the branch in another shopping mall. After closer inspection, it was uncovered that the shopping mall management was adding 5% to the electricity bill even though no such clause was stated in the written agreement. After this issue was uncovered thanks to the measurements that are done by Power Factor Controller, the 5% addition on the electricity bills was stopped and the shopping mall management paid the store €6.200 by preparing a retroactive payment bill.

It was determined that the inputs of current transformers were connected in reverse to the different branded power factor controller relay in the branch in a shopping mall in Ankara. This issue was resolved by replacing the older relay with a Power Factor Controller which has the feature to detect wrong connections and correct them automatically in the measurements.

It was determined that the electricity bill of a branch in a shopping mall in Istanbul was calculated with a 100% addition because the bill was calculated with the current transformer ratio as 160 instead of 80. The shopping mall management admitted the mistake and paid the store €24.900 by preparing a retroactive payment bill.

Conclusion

Thanks to all these measures taken, all 58 branches of stores were saved from paying penalty fee on their electricity bills for excessive reactive power consumption and the store chains cut back 13% of their previous electricity bill. The installed devices paid back themselves in just 1 month.