Energy efficiency is the key term for understanding the concept of cogeneration.
Basically, cogeneration is a process that transforms and reuses energy generated by a source.
During alcohol production, for example, steam is generated that can be used for cooking, drying, heating, distillation, and other purposes.
Thus, there’s no waste of an energy source: it’s an environmentally smart process that avoids the extraction of natural coal, diesel, or natural gas.
Cogeneration is widely used in the sugarcane industry, where processing sugarcane to obtain an energy source — alcohol — generates steam that’s reused to power machines, turbines, and the essential electricity during this same process. This cycle is what we call cogeneration, meaning that during the development of one type of energy (alcohol), another (thermal energy) can be obtained.
In Brazil alone, cogeneration was responsible for nearly 5% of all electricity produced in the country during the 1980s.
Nowadays, energy reuse is even more effective, as cogeneration is also applied in commercial buildings that use heat (hot water or steam).
In this case, thermal energy comes from electricity.
Among the sectors that most utilize the concept of cogeneration, chemical, pharmaceutical, petrochemical, beverage and food, paper, pulp, and textile industries stand out.
In all these, the goal is to reuse steam for heating.
Cogeneration is also used in high-temperature furnaces in the glass, cement, and steel industries.
In the commercial sector, it’s applied for water heating and central air conditioning in malls, supermarkets, hotels, sports clubs, among others.
Advantages of cogeneration:
- Lower cost of thermal and electrical energy
- Thermal energy from cogeneration is of high quality and reliability
- Savings in energy transmission and distribution
- Reduction in atmospheric pollutant emissions, making it one of the most sustainable energy processes in the world
In countries like the Netherlands and Finland, cogeneration accounts for about 40% of all energy power used.
Disadvantage:
- Physical limitation, as steam reuse can only be applied near the equipment that generated such thermal energy.
