Energy Efficiency and Biofuel (E2B) Project

Biofuel Recovery Project


 The St. Cloud Wastewater Treatment Facility has installed biofuel conditioning equipment and a generator, to convert biofuel to electricity. Heat produced by the generator is recovered and used to heat buildings and the digestion process.



 Biofuel to Electricity - How Does it Work?


 Organic wastes carry energy to the digestion process. The digestion process extracts this energy in the form of biofuel. The biofuel feeds boilers to heat buildings and an engine-driven generator to produce electricity. The biofuel harvesting project converts organic wastes to renewable energy.
Diagram of the Biogas Utilization Process

Sustainability


  At 100% efficiency, the biofuel generator has the potential to generate 5.4 Million kWh's of electricity annually. Prior to 2016, The St. Cloud Wastewater Treatment Facility purchased a little over 5 Million kWh's of electricity to treat over 9.8 Million gallons of influent flow a day. Whereas, in 2018, The St. Cloud Wastewater Treatment Facility purchased 700,000 kWh's of electricity. Depending on daily conditions, such as solar energy potential, some days the facility will be running at nearly 100% renewable energy.
 
 In 2018, 87% of the St. Cloud Wastewater facility's energy demand came from renewable sources.
Diagram of energy use equivalencies for 5 million kilowatt-hours