Introduction:

In the of era of high energy efficiency and sustainability whole world is searching most energy efficient technologies.

In this connection all industries have lot of choices, like use of cleaner technologies, CCUS (Carbon capture use & storage), Renewable Energy integration (RE integration) and obviously using low quality heat for chillers & refrigeration.

Trigeneration plants can be a game-changing solution for modern industries.

Trigeneration, or Combined Cooling, Heat, and Power (CCHP), simultaneously producing electricity, heat, and cooling from a single energy source.

This is basically an extension of co-generation plant, by using remaining heat for chillers/refrigeration.

This process, thus, maximizes energy utilization and offers unparalleled efficiency benefits.

What is Trigeneration

In a trigeneration system, high-temperature heat (steam/Flue gases) first drives a gas or steam turbine.

Steam turbine / Gas turbine coupled with generator produces electrical energy. In addition to the electrical energy production, steam can be extracted from the steam turbine intermediate stages, for further use in the process.

The residual heat available from a cogeneration system is further utilized to operate a vapor absorption refrigeration (VARS) system to produce space cooling/ chilling.

Thus Tri-generation system can attain higher overall efficiencies than cogeneration or traditional power plants.

The final gain is maximising the use of energy and thus cost saving.

This also reduces GHG emission and in turn reduces global warming.

Following digram is from PNGEngg courtesy

Why Trigeneration?

Trigeneration systems can achieve efficiency levels of up to 90%, compared to around 40-60% for traditional power generation methods.

This dramatic increase in efficiency contributes into substantial fuel cost savings and thus reduction of energy bills.

It also significantly reduces in greenhouse gas emissions (GHG emission), making it a key contributor to sustainability goals.

There are a number of benefits to trigeneration system as follows:

1. It Reduces fuel and energy costs.
2. High overall efficiency can be achieved.
3. Overall hear rate can be reduced.
4. Lower electrical usage during peak summer demand.
5. Engine heat can be used to produce steam of hot water for onsite use.
6. It reduces significant greenhouse gas emissions.

It uses no environmental pollutants since water is used as the refrigerant.

Working principle of Trigeneration plant:

Trigeneration plant is commonly referred to by Combined Cooling, Heating and Power (CCHP).

The main difference is in the fact that trigeneration technology is practically an extension of cogeneration plant by implementing the recovery of thermal energy for producing cooling energy.

By adding cooling energy in addition to thermal & electrical energy, the overall efficiency is much higher than cogeneration system.

With the help of a vapour absorption refrigeration system (VARS), the heat that is produced by cogeneration plant is used in producing space / air chilling effect .

lithium bromide or ammonia is used as absorbent and water is used as refrigerant. Hence harmful greenhouse gases are avoided.

Different types of Tri-generation plants:

Trigeneration plants can be of various types based on the basis of the initial fuel, through which the plant is fed.

Following are the common fuels used in Trigeneration plant:

• Coal
• Natural Gas
• Diesel
• Naphtha
• Biomass
• Biogas

Applications of Tri-generation system:

A trigeneration plant can be used in following industrial operations:

• Coal/ Gas based Power plants.
• Refineries & Petrochemicals.
• Co-generation plants.
• Chemical / Fertilizer plants.
• Paper plants.

The heat produced by combustion allows a significant use of energy, which in turn has a major impact on saving money and reducing greenhouse gas emissions into the atmosphere.

Advantages of Trigeneration

Trigeneration is an attractive option for energy efficiency scaling up.

However, it is best fit in buildings or large residential complexes where electricity, heating and cooling are perpetually needed.

Following are the areas where the trigeneration benefits can also be used economically, if suited geographycally (In global scenario):

Large manufacturing facilities.

Universities.

Hospitals.

Malls.

Universities and colleges.

However, it is to be noted that in India, extending the trigeneration facility is difficult, as most of the Cogeneration plants are remotely situated or catering their own needs in the industrial complex.

Conclusion:

By simultaneously producing electricity, heating, and cooling from a single fuel source, trigeneration systems can achieve unparalleled energy utilization rates of up to 90%.

This efficiency improvement translates into substantial cost savings, reduced carbon emissions, and a significantly smaller environmental footprint for industries.

Apart from the economic and ecological benefits, trigeneration offers excellent reliability and energy security.

It ensures a continuous power supply even in the face of grid instability.

It is adaptable to various fuel sources, including natural gas and renewable energy thus enhances its resilience and aligns with ever evolving sustainability goals.