a b s t r a c tUtility-based Demand-Side Management (DSM) programmes started after the oil crises of the 70's and were adopted by utilities as a standard practice. However, deregulation of the electricity industry threatened DSM. More recent concerns regarding energy dependence and environmental impact of energy use caused renewed attention on the utilities role in energy efficiency fostering. EE is presently a cross-cutting issue, influencing energy policy definition and regulatory activity worldwide. Some instruments for influencing the behaviour of electric utilities in the market are used by regulators, corresponding to both impositions and stimuli, such as defining savings targets or decoupling profits from energy sales. The paper addresses categories of regulatory instruments and refers to examples of countries and regions using these identified categories of instruments. Although some cases show voluntary involvement of utilities in EE promotion on the grounds of customer retention strategies, there is a clear prevalence of regulatory constrained markets where utilities rationally engage in energy efficiency promotion.

The proliferation of residential photovoltaic (PV) prosumers leads to detrimental impacts on the low-voltage (LV) distribution network operation such as reverse power flow, voltage fluctuations and voltage imbalances. This is due to the fact that the strategies for the PV inverters are usually designed to obtain the maximum energy from the panels. The most recent approach to these issues involves new inverter-based solutions. This paper proposes a novel comprehensive control strategy for the power electronic converters associated with PV installations to improve the operational performance of a four-wire LV distribution network. The objectives are to try to balance the currents demanded by consumers and to compensate the reactive power demanded by them at the expense of the remaining converters’ capacity. The strategy is implemented in each consumer installation, constituting a decentralized or distributed control and allowing its practical implementation based on local measurements. The algorithms were tested, in a yearly simulation horizon, on a typical Portuguese LV network to verify the impact of the high integration of the renewable energy sources in the network and the effectiveness and applicability of the proposed approach.

No abstract