In the refrigeration sector, the control of temperature and relative air humidity during storage and transport of goods, consumes large amounts of energy. In fact, when applying best available technologies to control temperature and relative humidity of air, a large amount of electrical energy is needed because water vapour in air causes ice formation on the cold surfaces of evaporators (typically at –25°C) which lowers their efficiency and requires the use of expensive defrosting cycles. As food transport accounts for 3 to 4 % of total CO2 emissions in the EU, greater efforts are necessary to improve the energy performance of equipment and to develop new refrigerants with lower environmental impact.
The project aimed at demonstrating the environmental, technical and economic viability of a technology designed to minimise the formation of ice on evaporator surfaces of traditional vapour compression refrigeration cycles in refrigerated trucks and storage cells. It assessed the reduction of CO2 emissions due to the use of less electrical energy, and reduction in the use of refrigerants due to the higher efficiency of evaporators, as well as the reduction in the use of electrical energy by BAT-refrigeration equipment. The results will be disseminated among EU universities, major industries and industrial associations.
The project demonstrated the technical feasibility of a process aimed at reducing ice formation in the refrigerators, using an air drying technology through a desiccant liquid. In addition, it suggested a means of greatly reducing energy consumption and consequently the cost and greenhouse gas emissions. However, this possible method was only demonstrated by a simulation programme. The experimental results showed about the same energy consumption as the traditional technologies. The problem could be overcome by optimising the energy efficiency of the auxiliaries of the plant, i.e. pumps, fan and heat exchanger. The simulation programme shows that the energy saving is theoretically possible: if the auxiliaries are optimised, the energy saving can reach and even exceed 20%, especially if the membrane area is larger than that used in the experiments. This could be a worthwhile After LIFE implementation programme. The new system can be applied to many different industrial sectors (such as humidity control in surgeries, museums, etc.), where this objective could be easily reached with a strong energy saving in comparison with traditional dehumidifiers, because dehumidification is achieved without a cooling process. Other applications might include processes where free heat is available, such as industrial hot gases, which otherwise would be wasted. In the coming years, the beneficiary intends to:
- Keep the website updated with the future experimentation results.
- Diffuse the technology’s future results through conferences, meetings, workshops, and involving the interest groups.
- Publish results and technical issues in specialist magazines.
- Offer training courses.
The beneficiary is in contact with several potential end-users in order to construct new plants on an industrial scale. It also intends to conduct, in co-operation with the project’s partners, studies and experiments aimed at improving both the system and its applications. The beneficiary also plans to continue those activities related to creating the conditions for new jobs.