SHOPPING CENTRES AND BUSINESS CENTRES

Modern shopping malls, which include shops, restaurants, cinemas, etc., regardless of their size, have high energy costs, given their electricity, heating and cooling (air conditioning) needs. Air conditioning systems account for a large share of the total electrical capacity of shopping malls.

Given the characteristics of shopping malls, significant cost reductions can be achieved through the construction of mini-cogeneration plants based on gas engines INNIO Jenbacher with cogeneration or trigeneration technology.

How does it work

Trigeneration is a combined production of electricity, heat and cold. From a technological point of view, this refers to the connection of a cogeneration unit with an absorption cooling plant (ABCP). The source of thermal energy for the ABCP is a by-product of the cogeneration unit – heat from the cooling system and exhaust gases.

Let us consider a TEC with a mini-CHP:

• Electric capacity 4,5 MW (3 JENBACHER J 420 GS gas engine units of 1,5 MWe)
• Heat output 6 MW (1.5 MW gas-fired generators + 2.1 MW hot water boiler)
• 6 MW cooling capacity (2 MWe ABCP and 5 MWe steam-compression chillers).

In winter, all heat power is used for heating, ventilation and hot water supply. In summer, only 1.5 MW of heat is needed to meet the needs of the shopping and entertainment centre. Accordingly, the excess heat energy of 2.4 MW is sent to the ABCP, we get (2.4 x 0.7) 1.68 MW of cold for air conditioning the complex.

Considering that we get the cold from the waste heat, the mall reduces the electricity consumption, because the cold does not have to be obtained at the compression chillers.

Benefits and Features

• Efficiency and energy independence. In-house generation provides cheap electricity, saves on connection to the local external grid, as only back-up capacity is needed, avoids electricity losses at transformer substations, and avoids the cost of laying power lines and installing additional equipment.

• Reduced capital costs. By utilising the heat from the mini-CHP, there is no need to build a boiler house to its full stated capacity. Only a peak boiler house is required and a single gas pipeline is used to supply the gas for the entire power unit, which is housed in a single building.

• Reduced air conditioning costs. Absorption chillers are an alternative to industrial air conditioners, which significantly increase the electricity consumption of shopping centres. The use of waste heat from mini-CHPs provides relatively cheap refrigeration.

• Environment. By using exhaust gases to generate usable energy, we reduce emissions into the atmosphere. Unlike traditional refrigeration technologies, where ammonia and freons are the refrigerants, ABCP uses water as the refrigerant, which minimises the environmental load.

The basic prerequisite for a successful trigeneration energy center is a professional approach to the conception, design and implementation of the project. KTS Engineering’s team is ready to assist in the realization of trigeneration projects, using global best practice and JENBACHER’s international experience.