Borås, a city of about 110,000 habitants in the south west of Sweden, has pushed the sustainability envelope for a long time. Borås Energi och Miljö AB, the municipal body responsible for energy supply, decided a few years ago to build a new Energy and Environmental Centre (EMC) - with a new sewage treatment plant, to future ready the city's growth capability and reduce its environmental impact. Heat production from the new plant started in 2018.
The project involved the construction of a new biofuel combined heat and power (CHP) plant (120 MWth), a new wastewater treatment plant (150,000 PE), and a biogas production plant located on an existing site about 5km south of the city.
The city of Borås is upgrading existing assets, like many Swedish municipalities that count on district heating for their heat supply. In Sweden, district heating systems account for approximately 60% of heating of buildings.
WSP started working with the municipality in 2011. In the early stages of the project, we provided consultancy and expertise in the development of a vision and strategic planning, and identified possible synergies between the various facilities.
Our experts also supported management in the investment decision process.
WSP then produced technical descriptions for the environmental permitting related to the CHP plant, and carried out pre-engineering studies for the plant's processes and buildings. WSP produced documentation for the procurement of the boiler, steam turbines and biofuel production, as well as techno-economical optimization of the CHP plant size and configuration with respect to future needs in district heating.
A Challenging Energy Project
The EMC project offered unique challenges because of the complexity of designing and building different plants at the same site, and under a constricted time schedule.
We played different roles during the project including overall project director (CHP, sewage water treatment, biogas etc.), multidisciplinary project manager for CHP, process interface management, design team leaders and design engineers for the water, raw sewage and district heating pipes between the city and the site. WSP also did the detail engineering of the sewage pumping station, which is one of the biggest in Scandinavia in terms of installed power.
WSP brought all the competencies and resources needed to make the project a success. Our teams of design engineers, multidisciplinary experts and managers, as well as our local understanding allowed for close co-operation with all stakeholders.
More information about this district heating project can be found in this presentation, from Borås och Miljö AB.