Combined heat & power plant connection into urban distribution network according to least cost technically acceptable principle

The aim of this paper is to give insight in the Combined Heat and Power (CHP) plant connection method into the Urban Distribution Network (UDN) based on Least Cost Technically Acceptable (LCTA) principle and impact of the most dominant UDN technical, operational and economic constraints that influence the connection method. There is no general agreement regarding the practice concerning the optimal allocation of financial responsibility for the CHP plant connection cost in the UDN. The differences in policies for the connection charges are substantial. They reflect the fact that different connection principles and policies consideration, each reasonable and valid, lead to different conclusion. The main goal of the planning process is to ensure that the UDN is developed in an orderly and cost effective way; Urban Distribution Network planner (UDNP) and Urban Distribution Network Operator (UDNO) must ensure that there is sufficient UDN capacity is available to meet new loads and CHP system connection as they arise, and to meet on-going growth and requirements. They also need to ensure that new connections are completed as technically/economically acceptable and able to meet the possible future needs of the customer/prosumers. UDNO is obliged to provide the CHP system developer with connection under acceptable standards as detailed in the UDN Distributed Code. If higher standard or higher security of CHP generation connection is required it can be provided at the CHP system developer´s request, however the full additional costs will be assign to the developer. In order to complete the CHP system connection into the UDN according to the LCTA principle the following sensitivity analysis of technical constraints are necessary to be performed as part of the connection process and these include: Equipment ratings, Protection settings, Voltage profile and Network losses. Based on the results obtained from these sensitivity analysis the UDNP/UDNO will determine a connection method which complies with the UDN appropriate standards and planning criteria.