Investment in green electricity generation is normally associated with certain risk. There are several risks that have to be taken into account and seriously analyzed before the investment decision. Typically one can distinguish risks related to technology, risks related to electricity market, risks related to legislative and political frameworks. Many authors distinguish public support as an important risk category. Often risks transform into real obstacles to start-up and operation of green electricity generation business. The paper particularly looks into investment capital and electricity generation costs as key obstacles to competitiveness of green electricity generation business. Investment costs and operation costs of green technologies are compared against those of fossil fuel technologies. The paper concludes that only in certain cases green electricity generation can compete with electricity generation from the traditional energy sources such as gas, coal or nuclear power.