Possibilities for energy recovery from sludge at Chişinȃu wastewater treatment plant have been investigated and evaluated. One way of recovering energy from sludge is to produce biogas through anaerobic digestion. Which method of biogas usage that is to prefer in Chişinȃu has been evaluated from a cost-efficiency point of view. There is a possibility that a new waste incineration plant will be built next to the wastewater treatment plant, and therefore solutions that benefit from a co-operation have been discussed. The results show that biogas production would be suitable and profitable in a long time perspective if the gas is used for combined heat and power production. Though, the rather high, economical interest rates in Moldova are an obstacle for profitability.