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Robur gas-fired absorption chillers & heat pumps


Why Robur chillers and heat pumps?

Robur chillers and heat pumps are ideal for any commercial or industrial cooling or heating application, but show major benefits where there are one or more of the following concerns :


Electrical Supply Issues


Robur units are ideal for sites where existing electricity supplies are at a saturation levels and additional or new cooling cannot be installed or sites where electrical power needs to be “released” for other usage.

The basic 17.7 kW cooling module only needs 820 Watts of single phase electricity to operate – compared with typically 6,000 Watts for an equivalent conventional air conditioner.


Carbon Footprint


All electric chillers contribute to global warming on two fronts, directly through the gradual leakage of greenhouse gas refrigerants (HFCs) from the plant and indirectly through the CO2 emissions resulting from the use of fossil fuels burned to generate the electricity required to operate the device.

The use of a natural ammonia/water mixture as the refrigerant in place of the more conventional HFC refrigerant gives the air cooled Robur system a major plus in the battle against global warming and is a useful answer to the dictates of the Fgas Regulations.

As well has having an ozone depletion potential of zero, Ammonia has a global warming potential of zero with an atmospheric life cycle of less than a week. In addition, the factory sealed refrigerant system of the Robur chiller means that the opportunities for refrigerant leakage are much less than those of a conventional electric HFC based system.

The direct use of gas at the point of source means that the CO2 emissions associated with the use of Robur chillers and heat pumps will be lower than those of equivalent alternatives when operating, power generation and transmission efficiencies are taken into account.

As an example, to generate a 100kW of hot water using a typical gas boiler would use around 120kW of gas whereas a Robur chiller/heat pump would only use 71kW of gas. Typically, this equates to a saving of 3.9 Tonnes of CO2 per year.

Please contact Shorts for advice on and assistance with calculating Total Equivalent Warming Impact (TEWI) and Life Cycle Climate Performance (LCCP) indicators.


Running Costs


Environmental benefits of any plant invariably go hand in hand with improved efficiency and reduced running costs. Robur chillers and heat pumps are no different.

The amount of running cost savings from using Robur chillers over and above equivalent electrically powered machines depends very much on the individual installation’s utility tariffs and running hours. However, in most instances where there is a heating requirement there will be considerable running cost savings over both conventional gas-fired boiler systems and electric heat pump systems.

Unlike electric heat pumps, Robur heat pumps can maintain their output capacity and operating efficiency (and therefore running cost savings) at ambient temperatures as low as -20 oC. Conventional air source electric heat pumps generally only operate effectively to -10 oC ambient, after which supplementary heating is required. Not only does this result in higher capital costs but the running costs of the supplementary heating will be higher and more environmentally damaging.

Please contact Shorts for advice on and assistance with calculating comparative Running Costs, Payback Periods and Life Cycle Costings.


Equipment Reliability


As the Robur absorption cycle uses a factory sealed refrigerant circuit with no compressor, it’s general mechanical reliability is excellent and the scope for refrigerant loss is minimised.

In the rare event of a refrigerant leak, unlike the odourless HFC refrigerants, the very smallest escape of Ammonia (well below any safety levels) is detectable through its characteristic odour. This is complimented by the fact that most of the Robur units are installed outside and ammonia is 1.7 times lighter than air, so any small leak quickly disperses into the atmosphere. Ammonia is difficult to ignite and exhibits a very narrow range of flammability (under very high concentrations and limited conditions).

In addition, the modular system approach to meeting cooling and heating loads means that the building is not solely dependent on one piece of plant and general wear and tear can be spread throughout the system by alternating “lead” units.

Robur’s integral control system monitors specific parameters and warns of factors that may lead to problems in the future, such as blocked air coil or reduced chilled water flow rates etc