Refrigeration and environmental and economic challenges

Refrigeration and environmental and economic challenges
Luca Tarantolo, Energy Efficiency Manager – Manni Energy – Manni Group

The refrigeration and air conditioning sector weighs by about 20% on global electricity consumptions, representing almost 8% of global greenhouse emissions. The latter are given by 37% by direct emissions caused by fluorinated gases whereas 63% by indirect emissions for the electric energy production.

If we remain in the analysis perimeter of a refrigeration plant and of the site hosting it, the amelioration strategies can be mainly grouped in two categories: the reduction of direct emissions mainly caused by the releases of refrigerating gas into the atmosphere, and the reduction of indirect emissions, connected with the use of materials and with the electric energy.

The reduction of direct emissions essentially implies the prevention of gas leaks and periodical controls. It is possible to focus on the problem root, at the engineering side, considering the use of a low-impact refrigerating gas (natural or synthetic gas with low GWP) and the minimization of the present charge, taking into account the problems connected with safety in case of toxic and/or flammable gases.

The exercise phase is especially characterized by management costs and by indirect emissions deriving from the use of electric energy.

Concerning the reduction of indirect emissions caused by production, transport and disposal of the refrigerating gas, it is possible to consider options such as the reuse, the recycling and the regeneration. An analogue reasoning can be done also for the construction material.

In order to make a comparison of the various options, from time to time it is necessary to refer to significant acknowledged indicators.

In the economic ambit, assessments should preferably use tools like the Life Cycle Cost Analysis (LCCA) or the cos analysis in the lifecycle (also called Total Cost of Ownership – TCO) that, besides considering the initial costs, such as purchase and installation ones, also includes the management costs like energy spending, maintenance and financial burdens, up to disposal and recovery costs. Such approach is also indicated as preferential by the Enclosure 2 of the Lgs. D. 102/2014 that defines the criteria for the execution of energy diagnoses.

In the environmental front it is possible to refer to indicators such as TEWI (Total Equivalent Warming Impact), which considers both direct and indirect emissions, being based on the GWP of the refrigerating gas and on emission factor of the electric energy used for the operation, or the LCCWI (Life Cycle Global Warming Impact) and LCCP (Life Cycle Climate Performance), which extend the TEWI concept considering also the emissions for the production, transport and recycling of refrigerants. For more structured analyses, we refer to the LCA (Life Cycle Assessment), as defined by ISO UNI EN 14044, based on the lifecycle of a specific product, and the CFA (Carbon Footprint Assessment), based on the ISO/TS 14067, aimed at the calculation of a specific impact.

In conclusion, the new scenario that today concerns the cold world imposes choices that take into account the constraints imposed by environmental policies and by the trend of energy markets. Such choices must be characterized with suitable indicators referring to standardized acknowledged methodologies, involving competent technical figures who are able to evaluate the various technical, economic and environmental aspects of refrigeration plants’ lifecycle.