Present and Future Status of Power-Based Tariffs : Study on the effect of the energy transition on power tariffs and their applicability

Abstract: Power and energy tariffs and their pricing are a vital component which form the main source of income for all actors in the energy industry. Different methods of how to price the energy have been proposed and implemented through the past century, each with its respective advantages and disadvantages. However, in the recent decades, interest has turned towards having power-based tariffs, since it’s the power dimensioning that counts for the majority of the costs. Sala-Heby Energi Elnät AB is local, publicly-owned Swedish distribution system operator which has been using a power-based tariff system for the last 15 years. That being said, the company has an upper limit for their net income which should not be overpassed. With the ongoing energy transition, where the number of electric vehicles in circulation is going up, and more customers turning towards residential micro-production, such a tariff might require modifications. In addition, a look on how the demand will evolve will be needed to see if the grid could handle such a transition. In this paper, a thorough study is conducted on how the energy transition would look like in Sala, Sweden, and what Sala-Heby Energi Elnät AB would expect. A simulation of the total residential load curve of the city is developed and ran via MATLAB and consumption data offered by Sala-Heby Energi Elnät AB. It involved generating an average residence based on the fuse size, which would yield the annual consumption profile to be used. The simulations were also done for several scenarios of different electric vehicle charging routines. They also take into account several residential PV systems coverages in the said city. Depending on which scenario, a rise or a drop in the net income is recorded. Modifications to the power tariff are explored based on that would help counter the fluctuations in the income, and simulated to track their effect. Another aspect that is studied is the subscription capacity to the grid by the operator to the respective power generation. Depending also on the scenario, various excessive consumptions peaks are recorded, which could pave the way to more difficulty in handling the grid.