Electricity has become a commodity capable of being bought, sold or traded. An electricity market is a system enabling purchases, through bids to buy or offers to sell, which can be useful for companies to lower electricity costs by short term trades. This new approach demands new ways of collecting, analysing and predicting not only electricity price, but in first place electricity consumption. The aim of the paper is to model electricity consumption of a manufacturing company. The trend, seasonal and random component, respectively, are identified.