Cases Studies : Harp Guinness Subsidiary (Ireland)

Harp Guinness Subsidiary (Ireland)

Lower investment and high running cost savings

Two STL-N10-100
provide cooling energy
at the lowest cost.

Harp Guinness Installation

Harp Brewery in Dundalk (Ireland-E.U.) produces 1 000 000 hectoliters of lager per year and consumes 12 000 000 kWh of electricity (4 000 000 kWh for the refrigerant plant). In 1992 Harp decided to modernise its refrigeration plant.
The existing system consisted of a wide range of process cooling loads satisfied by two circuits, a high temperature circuit at -8°C and a low temperature circuit at -12°C. During the design stage it was decided to install a Cristopia Thermal Energy Storage System (STL) on the high temperature circuit.

The STL reduces the instantaneous peak refrigeration demand by as much as 45 % by shifting daily 10 000 kWh from day to night.

Technical Data

Daily Cooling Energy Consumption	:	44 000 kWh
Maximum Cooling Demand	:	4 000 kW
Cooling Energy Stored	:	10 000 kWh
Storage Temperature	:	-10.4°C
Store Type	:	STL - N10 - 200
Nodules Type	:	SN.10
Number of Tanks	:	2
Tank Diameter	:	3 m
Tank Height	:	14 m

Characteristics

To further improve the system efficiency and to reduce electrical cost, it was proposed to install a Cristopia STL-N10-200 thermal storage system to shift electrical consumption to off peak period and to reduce the peak period electrical demand. To achieve this, a STL-N10-200 was specified storing 10 000 kWh at -10°C during night time off peak tariff period. The STL, also, reduces day time chiller power by 1 000 kWe.
The STL-N10-200 is composed of two 100 m³ vertical tanks filled with SN.10 (77 mm diameter) nodules. The nodules are filled with PCM (Phase Change Material) allowing thermal storage at -10°C.

Technical Advantages

Smaller chiller capacity
Stable flow temperature
Electrical supply reduced by 1 000 kWe
Refrigerant efficiency improved
Servicing simplified
Back-up at disposal
Smaller cooling towers

Projects Credits

Customer: Harp Ltd
Consultant: Integrated Energy Systems
Installing Company: Harp Ltd

Harp Guinness

The STL has reduced the maximum
demand by 1 MW and the cooling
consumption by 16%

Financial Advantages

The solution with STL costs less than the classical system with chillers
Saving on maintenance costs
Electrical supply reduced by 1 000 kWe
Saving on demand charge and energy cost (kWe)

Environmental Advantages

Refrigerant charge reduced (ozone layer protection)
Emission of CO₂, SO₂ and N₂O reduced (greenhouse effect)