Trigeneration/CCHP

Trigeneration, also referred to as combined cooling, heat, and power (CCHP), involves utilizing a portion of the heat generated by a cogeneration plant to

produce chilled water for air conditioning or refrigeration purposes. This is achieved by connecting an absorption chiller to the combined heat and power (CHP)

setup. In the case of quadgeneration, this process is elevated with the inclusion of systems for extracting purified carbon dioxide from the engine exhaust.

In contrast, combined cooling and power (CCP) solely focuses on the use of electricity and cooling.

Benefits of Trigeneration

There are a number of benefits to trigeneration including:

Advantages of Onsite, High-Efficiency Electricity and Heat Production
Decreased Fuel and Energy Expenditures
Diminished Electricity Consumption during Peak Summer Demand
Utilization of Engine Heat for Generating Steam or Hot Water Onsite
Substantial Reductions in Greenhouse Gas Emissions
Absence of Harmful Chemical Pollutants due to Water-Based Refrigeration
Contributes to Enhanced Building Energy Efficiency Ratings

A variety of different fuels can be used to facilitate cogeneration. In gas engine applications CCHP equipment is typically applied to:

Commercial
Residential
Industrial
Biogas
Coal-gas

Trigeneration systems provide energy in three distinct forms: electricity, heat, and chilled water.

Absorption chillers present an economically and environmentally friendly substitute for traditional refrigeration methods. When integrating efficient, low-emission power generation equipment with absorption chillers, it enables peak fuel efficiency, eradication of detrimental refrigerants, and curtailed overall air emissions. Various configurations of CHP units exist that enable the derivation of refrigeration benefits. These include:

Absorption Chillers
Operation using hot water
Operation using steam
Direct heat via combustion
Compression-type refrigeration machines
Direct drive power
Electrical drive power

Integrating a CHP or cogeneration facility with an absorption refrigeration system permits the utilization of surplus seasonal heat for cooling purposes. The warm water extracted from the cooling circuit within the plant functions as the driving force for the absorption chiller. Additionally, the high-temperature exhaust gas produced by the gas engine can serve as an energy reservoir for steam generation, subsequently powering an exceptionally efficient double-effect steam chiller. As a result of this approach, up to 80% of the thermal output generated by the cogeneration plant can be transformed into chilled water. This strategy not only enhances year-round capacity utilization but also substantially elevates the overall efficiency of the cogeneration plant.

Advantages Versus Conventional Refrigeration

Absorption-based refrigeration technology represents a well-established and cost-effective solution for achieving reduced-emission air conditioning systems.

Operated through heat utilization, making use of readily available and affordable "excess energy"
Generation of electricity, which can be supplied to the power grid or employed to fulfill the plant's electricity needs
In colder periods, the heat can be harnessed to meet heating demands
Absorption chillers entail no mechanical components, translating to negligible wear and minimal maintenance expenses
Absorption systems operate silently
Costs for operation and the lifecycle are notably low
The use of water as a refrigerant substitutes the utilization of ozone-depleting substances.

Features

Around 150-170 kW of cooling output is typically needed for every 1,000 square meters of office space.
The unit of cold energy is often expressed in tonnes of refrigeration (TR). 1 TR (metric) equals 3.86 kWh, while 1 TR (US) is equivalent to
3.52 kWh.
The coefficient of performance (COP) quantifies the efficiency of an absorption chiller. For a hot water chiller, the COP ranges from 0.6 to 0.8,
and for a double-effect steam chiller, it falls between 1.2 and 1.3.
Utilizing lithium bromide salt can yield cold water temperatures as low as 4.5°C.
Ammonia can achieve temperatures as low as -60°C.