Expected Results

The first result of the project will be the study and identification of 4 to 6 heat pump applications with the following characteristics:

  • the use of a Natural refrigerant solution is clearly feasible and safe
  • the use of a Natural refrigerant solution shows potential for high efficiency
  • the selected applications show a large potential market
  • the targeted applications are favorable to the European Industry, i.e. with weak or null competition with low cost Asiatic equipment
  • the developed product can be a truly cost effective solution.

The result will be the definition of case studies satisfying the above stated characteristics, with a complete description of the equipment design requirements and operation characteristics, also including the demands and requirements in terms of control and connectivity into the Global Energy Systems in which each heat pump is going to be integrated. The following initial set of heat pumps has already been identified as potentially interesting.

Case

Fluid

Source

T(ºC)

Sink

T(ºC)

Application

(kW)

1

HC (Propane)

Air

-10 to 10

Water

40 to 50

Heating water

production

50

60

Low demand

of Sanitary hot water

2

HC (Propane)

Water (brine)

-5 to15

Water

40 to 50

Heating water

production

100

60

Low demand

of Sanitary hot water

3

HC (Butane)

Water

Neutral

loop at 25

Water

60

Sanitary

hot water production

50

4

CO2

Air

-10 to 10

Water

60

Sanitary

hot water production

50

5

CO2

Water

5 to 25

Water

70 to 90

High Temperature

water production

50

 

The second important result of the project will be the design and construction of heat pump components: compressors, evaporators, condensers, and auxiliaries, optimized for the use of each of the selected refrigerants: HCs and CO2.

This is a very important result since the available commercial components have been designed for the conventional refrigerants and there is an important margin for improvement if the designs are optimized for the new fluids, which have particular properties.

The development of compressors of commercial size for hydrocarbons is completely new. There is no commercially available product in the market for that range of capacities. Therefore, this is going to be a very important result of the project. The compressor design will be adjusted to the characteristics of the employed hydrocarbons and the design will be modified in order to avoid any safety problem related to the flammability of the refrigerant. This result will open up a new market for the heat pump applications targeted by the project, but it also has a good potential for exploitation for other applications in the cooling, refrigeration or industrial sectors, hence boosting the future development of HVAC and refrigeration technology employing hydrocarbons as the working fluid.

Compressors for CO2 already exist in the market but they are very recent. The main application at the moment has been in Refrigeration equipment in supermarkets. This project targets very different applications so that it is expected that considerable improvements can be obtained if the design is adjusted to the specific operating conditions of the targeted applications. Therefore, a new design is also targeted for CO2 leading to improved performance.

The heat exchangers for each solution will also have to be different from the normal designs employed for conventional refrigerants. The best possible design will be developed for the evaporator, condenser and desuperheater for each application with the objective of minimizing the required refrigerant charge and reducing the temperature difference between the refrigerant and the secondary fluid. Compact heat exchanger technologies will be employed. Therefore, also new designs, with maybe unique features, are going to be developed in the project.

The main result of the project will be of course the detailed design of each of the heat pumps: including the expansion valve, refrigerant circuit, receiver, intermediate heat exchangers, and the auxiliaries, as well as the control and all the necessary safety devices. All these components and the design of the layout and dimensions will have to consider very carefully the special requirements of hydrocarbons or CO2 and help to the objectives of maximizing efficiency and minimizing the refrigerant charge, and still resulting in a cost effective technology. This is a summary of the main features of the heat pump units to be developed:

o High efficiency: 10 to 20% increase on Seasonal Performance Factor (SPF) compared to current HFC’s and HFO’s equivalent equipment.

o Very Low CO2 emission: reduction of at least 20% of the Total Equivalent Warming Impact (TEWI) compared to current HFC’s and HFO’s equivalent equipment.

o Efficient and flexible capacity modulation. Maximum capabilities for integration in complex energy systems with different heat sources - sinks: simultaneous production of chilled water and hot water at various temperatures, smart control and connectivity to the Smart Thermal Energy Grid.

o Tight containment and minimum charge. Design incorporating all the necessary safety measures and high reliability.

o Affordable cost: similar to that of equivalent HFC’s or HFO’s solution or slightly higher (10%).