European Union Emission Trading Scheme (EU ETS) was introduced in EU countries in the year 2005. Currently, the EU ETS is in operation for more than a decade; moreover, the European Commission adopted rules for the next 4th trading period in March 2018. The main goal of this article is to evaluate possible environmental impacts of EU ETS, mainly the impact of emission allowance price on the amount of greenhouse gas emissions in the EU28 countries as a whole. For this goal, (geo)visual analysis of spatial data, correlation and regression analysis are used. The results of the analysis show that the EU ETS contributes to the reduction of the amount of greenhouse gas emissions in the EU-28 countries as a whole, due to emission allowances price and period. Nevertheless, the influence of the way of emission allowances distribution is crucial for the desirable environmental impact. The extension of auctioning represents our key recommendation for the EU ETS.