Due to the new EU regulations for the liberalisation of the electricity supply market, energy suppliers have, over the last decade, been faced with far-reaching changes in the market. Additional incentive systems for the promotion of quality measures were introduced at the same time as the liberalisation, to promote a high security of supply level. Power network operators are consequently motivated to take all the necessary technical measures that ensure stable network operation. In particular, they must ensure their network's reliability through long-term investment.
The starting point of analyses using PiReM is the adoption of a system-based overview off all the equipment is imported via a generic interface from the geographical information system into the PiReM database. In case there are additional sources that provide useful information (like SAP or network calculation systems), the inventory data can be supplemented and combined with such information. This makes possible the incorporation of cost-relevant information from business accounting, weighting according to network zones and other network topology criteria.
Initial analyses with PiReM indicated the network specific plant structures and provide an overview of the state of the supply network. Taking into account the aging behaviour, the technical service life and costs for the procurement of equipment PiReM forecasts the failure rate trends, the renewal requirement per equipment group and the long-term future rehabilitation and investment requirement. In making its calculation PiReM relies on the one hand on statistical methods, and on the other simultaneously on the long-term experience and network know-how of the company's experts who can make fine adjustment via PiReM flexible user interface.
The results of the long-term planning on projected damage, rehabilitation and cost trends are now operationalized in a list of priorities for concrete action. The forecasting model for medium-term replacement planning answers the following important questions:
The condition assessment in PIReM integrates external data that is collected through site inspections and administered in plan maintenance systems, such as SAP PM. These can be combined with the results of the PiReM condition analyses which in its calculation considers both the aging behaviour and the condition changes of equipment, as well as failure and fault statistics.
In PiReM, a valuable decision support system for selection of an appropriate rehabilitation strategy for power network equipment has been developed. Its integrated ''risk-orientated maintenance'' is the strategic approach, taking into account the importance and the condition of individual equipment items, to formulating a comprehensive strategy, which, combined with inspection measures, uncovers condition deterioration and the counteracts it by equipment renewal at an economical ideal time.
In a power supply network continuous aging and wear processes entail on going-investment. Budgets are limited and must be properly targeted to ensure a maximum network lifetime. PiReM indicates in the scenario forecast how investments affect the network lifetime and how the book value of plant assets changes over time. The condition class model not only forecasts the physical deterioration of the network equipment, but also indicates, through the saves commercial criteria , such as materials, labour and other costs as well as maintenance and inspection costs, the financial resources required, which are added to the medium-term planning of investment over the defined period.
Expert analyses using PiReM offer multi-utility companies a significant cost advantage through the exploitation of synergies and know-how transfer between the supply networks. In particular, potential cost savings through targeted-site coordination using PiReM are used, which can be achieved both within the company and also through cooperation with external network operators.
