Allocation of solar units to reduce annual costs of the distribution system

It is widely accepted that renewable sources can find their significant role in power distribution systems. These non-pollutant resources have a lot of advantages such as reducing active power loss, increasing reliability, supplying the peak load duration time, etc. This paper presents a solar unit planning considering uncertainty of solar radiance in order to reduce the costs of the distribution system including costs of energy loss, energy not supplied costs and the purchased power costs. The uncertainty of solar radiance is modeled with Beta probability density function. The planning problem is formulated as mixed integer nonlinear programming (MINLP) and is tested on a 9 bus distribution system using GAMS software. The results show a significant reduction in costs of distribution system in presence of solar units.