Modelling the impact of low carbon technologies on LV networks

A Probabilistic Impact Assessment methodology has been developed to understand how increased use of low carbon technologies (i.e., PV, EHP, EV) will affect the supply of electricity to our homes.

Project aims

Nowadays there is a large consensus about the necessity of decreasing the carbon emissions in our society. One alternative to face that challenge is to increase the use of domestic-scale low carbon technologies (e.g., photovoltaic systems (PV), electric heat pumps (EHP), electric vehicles (EV), micro combine heat and power (µCHP), etc.).

However, the adoption of these technologies might lead to some problems in low voltage (LV) distribution networks. For example, PV can produce voltage rise, increase energy losses, produce higher harmonic content, etc.

To assess the extent of these effects on the performance of LV networks, a Probabilistic Impact Assessment Methodology has been developed in this project. This methodology combines real networks, time-series analysis, a Monte Carlo approach for loads and LCT (considering hundreds of simulations to cater for behaviour, location and size), and the use of an unbalance power flow engine to assess the impacts.

Several metrics are used to assess the corresponding impacts. This includes percentage of customers with voltage problems per feeder, utilization level of the feeder, daily energy losses, probability distribution of having certain number of customers with problems, etc.

Applications

The electrical system that brings power to our homes was designed and installed when electricity was generated in large power stations and flowed in one direction to our homes.  The increased use of LCT is changing where within the system electricity is generated and how the electricity is used.  Companies that provide the electrical service to our homes need to be able to predict how the growth in the use of LCT will affect both the quality of the electrical supply we receive in our homes and the impact on the wires and transformers used to supply electricity.

The results of this work can be used by the companies who run the local electricity networks to enable them to better manage networks and reduce costs. Particularly, with the proposed probabilistic methodology, the Distribution Network Operator can analyse the potential risk (in terms of probabilities) of having a given LCT penetration in their networks and, therefore, prepare accordingly.

Future development

Having a better understanding about the impacts of LCT in LV distribution networks, the next question to solve is how to increase the penetration of these technologies by minimising the impacts in LV networks.

Some alternatives are being explored in the last part of this project, such us:

  • OLTC operation in MV/LV transformers,
  • meshing radial LV feeders
  • installation of energy storage at LV distribution level.

People

Academic staffDr Luis Nando Ochoa, Research staff: Dr Tuba Gozel

Research student: Mr Alejandro Navarro Espinosa

Funding

This Project has been funded by Electricity North West Ltd (ENWL), UK, through the Ofgem’s Low Carbon Networks Fund Tier 1 Project “LV Network Solutions”, 2011-2014.

Publications

  • Navarro Espinosa, L. F. Ochoa, and D. Randles, “Assessing the Benefits of Meshed Operation of LV Feeders with Low Carbon Technologies,” Innovative Smart Grid Technologies Conference (ISGT), Washington 2014 IEEE PES, vol., no., pp.1,5, 19-22 Feb. 2014. DOI:10.1109/ISGT.2014.6816494
  • Ballanti, A. Navarro Espinosa, L. F. Ochoa, and F. Pilo, “Assessing the Benefits of PV VAr Absorption on the Hosting Capacity of LV Feeders,” Innovative Smart Grid Technologies Europe (ISGT EUROPE), Copenhagen 2013 IEEE/PES, vol., no., pp.1,5, 6-9 Oct. 2013. DOI:10.1109/ISGTEurope.2013.6695423
  • Navarro Espinosa, L. F. Ochoa, P. Mancarella, and D. Randles, “Impacts of Photovoltaics on Low voltage Networks: A Case Study for the North West of England,” 22th International Conference on electricity Distribution (CIRED 2013), Stockholm 2013, no. June, pp. 10–13. DOI:10.1049/cp.2013.1229
  • Navarro Espinosa, L. F. Ochoa, and D. Randles, “Monte Carlo-Based Assessment of PV Impacts on Real UK Low Voltage Networks,” 2013 IEEE Power and Energy Society General Meeting, Vancouver 2013, pp. 1–5. DOI:10.1109/PESMG.2013.6672620
  • Navarro Espinosa, L. F. Ochoa, and P. Mancarella, “Learning from Residential Load Data: Impacts on LV Network Planning and Operation,” in Sixth IEEE PES Transmission and Distribution: Latin America Conference and Exposition, Montevideo 2012. DOI:10.1109/TDC-LA.2012.6319101
  • Navarro Espinosa and L. Ochoa, “On the Cascading Effects of Residential-Scale PV Disconnection Due to Voltage Rise”, 2014 IEEE Power and Energy Society General Meeting, Maryland 2014, pp. 1–5.
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