ENERGY SAVING EQUIPMENT
for business and a key differentiator. For example, part of our approach is to invest in providing consultants with the information needed to improve the energy efficiency of hydronic systems made of more than one unit in parallel connection and with the combination of production of cooling and heating.
The energy performance of a chiller or heat pump system, which consists of several units connected together, is not related to the technical characteristics of each unit only, but to the management system of all the units, that have to follow the continuously changing load demand of the building and produce water at different temperatures in relation to the need. The first issue is to define which type of units are most suitable to the particular characteristics of the installation as there is no single technology that offers the best efficiencies for all types of central system.
We address many parameters; the design of the installation, required cooling and heating load, climatic profile and the use of the facilities. We also take a detailed look at the profile of the load demand, the objectives of energy rating/ efficiency, investment plans, whether it is possible to use renewable energy (geothermal/solar), the space available for the units’ installation as well as noise levels, redundancy and maintenance. All of these parameters are necessary so that we can provide a customised and optimised proposal that meets the customer’s requirements. Selecting the products technology system is also key and subject to a comprehensive analysis which takes into account the behaviour of the performances of the unit when integrating with other units and with all components of the system, so we developed ACES (Aermec Chiller Efficiency Simulation) which is used to generate a comprehensive report.
Insufficient industry standards Like other HVAC manufacturers, we invest heavily, pushing the boundaries to achieve greater efficiencies with minimal environmental impact. But we believe that industry standards have a part to play and can drive more innovation. Currently the most widely used criterion for assessing the technical performances / efficiency of a chiller or heat pump unit is the SEER or SCOP data (Seasonal Energy Efficiency Ratio). This represents what would be the seasonal energy efficiency of a specific chiller or Heat Pump if it is installed in an area with a specific environmental profile as defined by the European Standard EN14825 (2018) and in use by Eurovent and if the nominal load required by the building coincides with the nominal capacity of the considered units.
However, these values are not a true representation of the value of the average annual efficiency of the units (or System). They only give a common reference that compares the efficiencies between different brands of chillers and heat pumps that work in a common annual duty cycle and with modulation levels as defined by the European Standard.
It could be argued that SEER and SCOP are not good mechanisms for comparing two or more unit groups, because the loads each unit has to provide to meet the actual demand of the building, may differ significantly from the assumptions determined by the European Standard. The European Standard does not consider the real climatic profile, nor does it take into account an oversized installed capacity, the number of start and stop cycles which impacts efficiencies.
When we try to analyse the performance of several units connected together, the SEER or SCOP values do not represent the global performance of the system, unless all units are working at the same conditions and at the same part load and temperatures.
It can be more realistic to define a sequence of start / stop of the units, taking into account water volumes in order to meet the load demand of the building, with a number of units in operation at a specific part load to meet the best individual efficiency.
Download the ACR News app today
Aermec’s Multichiller EVO is a management system that assesses the instantaneous load demand of buildings and determines how many units should work in cooling or heating mode at the best efficiency, being the instantaneous efficiency in relation to the water outlet temperature and the ambient temperature. The activation / deactivation of each chiller results in a variation of the primary water flows which in turn affects the pump energy consumption and has an influence on the bypass flows that is consequently affecting the mixed water temperature of the secondary circuit of the system. The Multichiller EVO activation/ deactivation sequence provides important analysis using all the key parameters, providing the correct rotation of units based on their running hours with priority given to certain particular units (for example units with heat recovery). Aermec’s philosophy is that we don’t just care about the products we manufacture, we take an holistic approach. This includes analysing how our products are used in a system and the needs of a building, which can make a significant difference. We all know what causes climate change and the best way to slow it is by reducing greenhouse gas emissions. We have many tools and technologies available right now that will help us deliver greater efficiencies and a faster return on investments, now is the time to deploy them. X
www.aermec.co.uk/
www.acr-news.com • January 2022 19
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48
