CIRED Workshop - Helsinki 14-15 June 2016 Paper 0339 Paper No 0339 Page 1 / 4 IMPACT OF LOAD AND GENERATION FLEXIBILITY ON THE LONG TERM PLANNING OF YLPIC DISTRIBUTION NETWORK Parvathy CHITTUR RAMASWAMY Benjamin PICART David VANGULICK Sébastien LEYDER Zacharie DE GRÈVE ORES - Belgium Stéphane RAPOPORT UMons- Belgium david.vangulick@ores.net Tractebel – Belgium Benjamin.picart@umons.ac.be parvathy.chittur@tractebel.engie.com Zacharie.degreve@umons.ac.be sebastien.leyder@tractebel.engie.com stephane.rapoport@tractebel.engie.com ABSTRACT Long-term investments planning of distribution networks are no longer limited to investments in electrical equipment, but can also include investments in information and communication technology (ICT) required to enable both load and generation flexibility. New factors such as flexible loads, distributed generation etc. should be taken into account in modern long-term planning. The advantages of load and generation flexibility can then be fully exploited to reduce the total investment cost. This paper studies the impact of load and generation flexibility on the long term planning of the YLPIC distribution network (a typical MV network that can be encountered in Wallonia, Belgium) using the Smart Sizing tool, currently developed by Tractebel. INTRODUCTION Long-term planning of distribution networks is a complex process [1] that has only become more difficult in the context of smart distribution systems. Network planning investigates the required network investments which in turn includes infrastructure costs and operation costs. Traditionally the infrastructure costs included the cost of transformer, cables etc. and the operation costs included the cost incurred due to losses in the network. However, in the smart distribution network, the key additional factor that can influence the planning is the flexibility in the network. Load shifting and generation curtailment are a couple of examples of flexibility. Thus, investments in infrastructure are no longer limited to investments in electrical equipment, but also include information and communication technology (ICT) investments. More importantly, the challenge and the value of network planning lies in the trade-off between the two types of infrastructure investment. Similarly, in smart distribution systems, the operation costs is not limited to the losses alone but also includes the cost incurred due to load and generation flexibility [2]. Here again, the trade- off between the two, that is the operation cost incurred due to losses and the one incurred due to flexibility, is interesting. Recent literature on planning attempts to adapt the traditional planning methodologies to fit in the smart grid context [3] – [7]. In addition, software tools are developed to aid the planner in the planning process. In this paper, the impact of load and generation flexibility on the long term planning of the YLPIC distribution network, a typical MV network that can be encountered in Wallonia (Belgium), is envisaged with the help of the Smart Sizing tool. Smart Sizing is a new network planning tool that fully takes into account the smart grids context. The Smart Sizing tool was first presented in [9]. The tool takes into account smart technologies such as distributed generation, load flexibility, and ICT. The role of the Smart Sizing tool in the long-term planning process is to find an ideal target network in terms of size of equipment, system architecture etc. A green field approach is envisaged in the tool. The target network is in that sense ideal, as it does not take into account the existing network. The results obtained from Smart Sizing can be used as guideline for the distribution system expansion planning [10]. The paper will first state the problem under consideration followed by the description of the methodology adopted to solve the problem. This is followed by the description of the YLPIC network and two case studies. The results of the two case studies are presented from which the conclusions derived. PROBLEM STATEMENT In this paper, long term planning of the HV/MV (70/10.5 kV) substation and of the MV network of YLPIC is envisaged. The objective involves, assessing the impact of load & generation flexibility in the planning of the distribution network. YLPIC includes the following: 1. The HV/MV substation (s) (70 kV/10.5 kV), 2. The MV (10.5 kV) network, 3. The MV/LV substations (10.5 kV/ 0.4kV) (mainly transformers) 4. The LV (0.4 kV) network However, out of the three voltage levels 70 kV, 10.5 kV & 0.4 kV, the optimal investment planning for two voltage levels (70 kV and 10.5 kV) are envisaged in this study as shown in Figure 1. The Wind generation is directly connected at the 10.5kV side of the 70/10.5 kV substation. All the other generation and load are connected along the feeders. Hence the wind generation affects only the HV/MV transformers and the HV cable sizing.