Cogeneration is a combination process that produces electrical and thermal energy, optimizing energy efficiency and limiting waste.
It is a cascading system, transforming the energy of the fuel used into electrical energy, and converts heat released during combustion into thermal energy.
Cogeneration plants can be powered by natural gas (methane), diesel or LPG. The plants are made up of an endothermic engine or gas turbine, combined with a three-phase generator for the production of electricity, and a heat exchanger.
The heat exchanger recovers thermal energy from the engine cooling circuit and high-temperature exhaust gases to produce steam, hot water or superheated water.
Cogeneration plants have a considerably higher overall efficiency than traditional thermoelectric power plants, thanks to the simultaneous harnessing and production of electric and thermal energy. There is a consequent energy saving, in comparison, and reduction of emissions into the atmosphere.
Thus, cogeneration is both a strategic choice and an opportunity for growth, in terms of image and competitiveness, for companies:
- Higher energy efficiency
- Greater economic savings
- Respect for the environment
Incentives are paid to support cogeneration systems too, as set out in the Decree of 5 September 2011 on the benefits derived from using high efficiency cogeneration (CAR) plants.
Costell offers a wide range of cogeneration plants, from traditional and renewable sources, from a few hundred to 4000 kWe of installed power. Each plant has its own characteristics, as determined from identifying the optimal solution for its specific application and energy needs.
For both traditional and renewable energy sources, Costell offers trigeneration plants — simultaneous production of electric, thermal and cooling energy.
The trigeneration system is made up of a cogenerator is combined with an absorption refrigeration unit. This unit changes harnessed thermal energy into cooling energy, through the change in state of the refrigerant fluid.
Compared to traditional systems, trigeneration presents a more optimal and economically advantageous solution for production cycles that require both power and electricity.
A turbogas plant is composed of a volumetric machine that sucks in air from the outside and, through energy from the combustible gas, simultaneously generates electrical and thermal energy.
This type of production is considerably affected by the temperature and humidity of the plant's environment. The combustion air–cooling systems (TIC) offered by Costell are designed to ensure an adequate cooling of incoming comburent air, for turbogas cogeneration plants. This ensures the gas turbines work within the ISO conditions of the project, even in summer.
The system works by having a series of radiant batteries positioned within the combustion air intake ducts, which are fed with chilled water (between 3 and 7°C), and take heat from the incoming air to reduce the air's temperature. The thermal energy leaving the batteries, in the form of now-hot water, is then sent to the plant's other production processes, or disposed of in a cooling tower.
Refrigeration can take place through:
- A centrifugal or screw compressor, powered by the factory's electricity network
- A thermal cascade absorber available on the site
- Bore water