Bulgaria expects bids for Sofia EfW plant by 15 March


After ten years of preparation and studies, the Sofia district heating utility announced a tender for the Sofia EfW plant to be operated by refuse-derived fuel (RDF), with the deadline for submitting bids set at 15 March 2021.

History of the project

In July 2011, the European Commission approved the first phase of Sofia’s municipal waste project, which is considered a priority due to Sofia's longstanding difficulties in securing waste-management facilities. Because phase one involved the construction of a landfill and two composting plants, the existing municipal waste separation facility in Suhodol was improved and a waste-separation system was set up in the Kremikovtsi (Gara Yana) area.

The EU also gave approval for the second phase – construction of a RDF plant – with investments provided by the EU Operational Programme Environment and the remaining funding received from the Sofia Municipality.

In 2012, Sofia CHP, Sofia’s heating utility, signed a contract for technical assistance on a combined heat and power generation plant on the site of one of its existing heating plants. Financed by the Kozloduy International Decommissioning Support Fund (KIDSF), the assignment was finalised in 2014.

The first phase of the programme was also completed in 2014 and was made up of four parts: construction of a 2,825,000 cubic metre landfill for disposal of non-hazardous waste; construction of a biowaste and garden-waste composting facility with a capacity for 20,000 tonnes per year (t/yr) for biowaste and 24,000 t/yr for garden waste; purchase and installation of equipment for an existing waste-sorting facility; and a pilot project for separate collection of packaging waste at source in two districts of Sofia.

The second phase, which ended in 2015, created improvements in recycling and established the mechanical biological treatment facility, which has an input capacity of 410,000 t/yr and can produce about 39,000 t/yr of recycled material and 180,000 t/yr of RDF (although yearly production levels vary).

The European Regional Development Fund (ERDF) co-financed the first and second phases, which received almost EUR 43 million and EUR 84 million respectively.


Construction of the RDF plant was scheduled to begin in November 2018, but obstacles, including ecological, technological and financial issues, delayed the development.

When up and running, the RDF combustion installation will provide free fuel for the Sofia CHP, which is expected to save of 65 million cubic meters of natural gas and up to EUR 18 million annually. The project received a positive Environmental Impact Assessment (EIA) in 2015, a Detailed Development Plan in 2016 and the green light for financing in 2017.

Scheduled for construction at an existing heat and power installation, the cogeneration plant is expected to process 180 000 t/yr of RDF. In addition, its energy recovery method and boiler design will ensure a high level of efficiency, allowing it to produce heat for 40,000 households and electricity for 30,000 households. The heat will be supplied to Sofia’s district heating network and the electricity will be fed into the national grid.

The project

Construction of the plant, which will produce 55 MW heat и 19 MW electricity and will be operated by a staff of up to 50, is scheduled to start in late 2021 and will be completed by the end of 2023.

Total investment for the project, including “design and construction of a cogeneration unit in Sofia for the utilisation of refuse-derived fuel – the third phase of an integrated system of municipal waste treatment facilities in Sofia Municipality”, is estimated at EUR 189,045,613, with the EU’s European Regional Development Fund contributing EUR 77,202,130 through the Environment Operational Programme for the 2014-2020 programming period. The investment falls under the priority of “Waste” management.

The tender

Interested EPC contractors must file bids by 15 March 2021. The EPC contract will follow the FIDIC Yellow book (1999) standard.

For more information on this project and the bidding process, contact your regular CMS source or local CMS experts: Kostadin Sirleshtov, Borislava Pokrass and Elena Yotova-Yordanova.