Distributed generation, energy storage and smart grid

Abstract

Distributed energy generation (DEG) systems are small-scale power generation units usually in the range of 1-10 000 kW without any special siting requirements that might be connected to the grid at the demand side. The concept is not brand new. For example, there were plenty of the so-called local hydro power stations in the rural areas of the Soviet Union in the beginning of 1950. The renaissance of DEG systems coincided with small wind generators and photovoltaic solar cells introduction in electricity markets of some western countries. In the so-called free market economy, it was obvious to encourage DEG development. So, since the beginning of 2000 many small generators were allowed to sell electricity back to the grid for the same price they would pay to buy it. The major investors in small-scale DEG projects have been unregulated independent power producers that sell their generated electric power to utilities usually under state -guaranteed long-term contracts.