To provide sustainable cooling and minimise the aforementioned risks in the most cost-effective way, it is helpful to consider five distinct steps in the design and use of cooling systems. If these steps are fully implemented, the cooling systems will have minimum cooling demand, be highly efficient and be well integrated with the power generation system.
Optimising the cooling demand should always be the first step – in many cases it will lead to a smaller system being required and a significant reduction in energy use. Savings of 30% to 60% are often possible. There are numerous ways in which this can be achieved, for example:
There can be massive differences between the energy consumption of different cooling systems used for the same application. There are many potential reasons for poor performance, falling into 5 main areas:
A sustainable cooling approach requires responsible use of the natural resources used to produce the cooling equipment (for example copper, aluminium, steel, refrigerants, etc…). This includes the need to reduce, recover and reuse these materials, contributing to a Circular Economy approach. Heating and cooling products are subject to different Regulations (e.g. in the EU: Ecodesign, RoHS, WEEE), and therefore contribute to Circular Economy across their whole lifecycle, for example:
The direct impact of refrigerants can be minimised by a combination of various factors, such as:
In most countries there is little or no interaction between decisions made to purchase cooling equipment and decisions affecting the supply of electricity. If end users continue to select inefficient cooling appliances, for example because they have the lowest capital cost, there will be unnecessarily high peak electrical demands created. These must be met by building extra power stations and by creating larger electricity transmission and distribution networks. Working in this way leads to:
To overcome this issue, there needs to be close cooperation between the parties involved, to create a more integrated approach to the delivery of more cooling and to optimise the balance of capital investment between new cooling equipment and power generation.
By encouraging end users to only use the most efficient equipment, the overall cost to the country or region can be minimised. This type of integration can be considered in a number of different ways:
To maximise the cost-effective uptake of renewable energy it is important to integrate the design of energy supply systems (supply side) with the design of energy using systems (demand side). This means, for example, that buildings need to be considered as a key element of the energy infrastructure with heating and cooling demand being at the core of long-term planning.
An important opportunity is to ensure optimal use of energy between different categories of users (residential/commercial/industrial), by coordinating building clusters at local and at city level. Such an approach enables the provision of minimal energy input, without sacrificing the functionality of the system (whether dedicated to comfort, manufacturing processes, or other functions).
Examples for system integration include: