The strong lobbying of industries and energy producers has overly diluted the EU's climate ambition. Considering the damage caused by climate-related problems, companies are paying bottom prices for CO2 emission permits, if they pay at all for them. The market isn't going to solve these problems because the current surplus of emission permits in the system is too large and politicians are to timid to make any meaningful changes.
That's why we should implement a bottom price for CO2-emission permits. The price of an emission allowance currently fluctuates around 18 euros, whereas studies have shown that a price of around 30 to 65 euros per tonne of CO2 in 2020 and 40 to 80 euros in 2030 is necessary to motivate companies to phase out coal and to counter global warming trends 
 J. Stiglitz and N. Stern (2017), Report of the High-Level Commission on Carbon Prices.