Following the famous quote of Lord Kelvin, “If you can not measure it, you can not improve it“.
This obviously applies to the optimization of energy consumption. You have to be able to measure energy consumption (electricity, gas, fuel oil, water) if you want to be able to understand where they come from. It is only from this detailed understanding that we can then define actions aimed at reducing this consumption.
Europe has set itself the goal of increasing its energy efficiency by 32.5% by 2030. Buildings also consume 40% of the energy used in Europe. Improving the energy efficiency of companies necessarily involves reducing consumption in its buildings. It is no coincidence that in France, the tertiary decree which applies to service companies, has set the objectives of reducing the energy footprint of buildings by 40% in 10 years, 50% in 20 years and 60 % in 30 years.
Can we reduce our consumption by 32.5% by 2023?
The answer is yes !
Practice has shown that the implementation of smart metering in a company allows, on average, a reduction of 10% to 20% of consumption. By Smart Metering, we mean the continuous measurement of consumption, the recovery of data in order to analyze it, and therefore to be able to define actions whose impact can then be measured.
A conclusive case study!
We did the exercise with a partner. And the results are up to expectations. 10% discount in a few months. Probably 10-20% off the first year.
To achieve this, the steps were as follows:
- During an initial audit, the main consumption classes were identified (heating/ventilation, electrical outlets, lighting, other consumption). This classification has enabled the implementation of consumption measurements
- Reduction targets have been defined. 4% annual discount. 40% in 10 years. The consumptions for a reference year (2019) have been uploaded to the platform, in order to be able to compare them with the current situation, while taking into account the differences from one winter to another (“warm” winters vs “warm” winters).
Analysis of consumption measurements.
The ability to view consumption, by type, but also by day (of the week, weekend), by time of day (and night) will provide a lot of information on the consumption profile, and on the nature/reason for these consumptions.
More advanced analytical data, such as consumption peaks (important when operators will charge according to the level and number of peaks measured), or even background consumption (minimum hourly consumption).
Based on this data, you can make decisions that will lead to reductions, sometimes substantial, of unnecessary consumption.
Synthetic Energy Indicators
What is my energy consumption per year and not m2? Per year and per employee? Per year and per ton of products generated. So many indicators that will also allow you to monitor your consumption over time, and to compare yourself to your competitors/neighbours.
Here are some examples of Energy Indicators in Belgium (Wallonia) – 2012. Of course the values depend on a lot of factors (geography, weather, industrialization level…)
Type of business | Electricity | Fossile |
|---|---|---|
Retail & Wholesale (421 – 2 320 m²) | 97kWh/m2 | 135kWh/m2 |
Retail & Wholesale (3 895 à 32 600 m²) | 73 kWh/m² | 64 kWh/m² |
Supermarkets (550 à 2 100 m²) | 454 kWh/m² | 162 kWh/m² |
Hypermarket (2 793 à 32 000 m²) | 292 kWh/m² | 143 kWh/m² |
Offices | 138 kWh/m² | 102 kWh/m² |
Public Sector | 65 kWh/m² | 165 kWh/m² |
Education | 27 kWh/m² | 127 kWh/m² |
Hotel | 111 kWh/m² | 204 kWh/m² |
Restaurant | 618 kWh/m² | 563 kWh/m² |
PEB Hospital in Brussels/Belgium
All Public entities in Brussels must publish their Energy Performance indicators. Here the Molière-Longchamp hospital in Brussels (IRIS-South network).
The “PEB” (Building Energy Performance) indicator is expressed in primary energies. 366 kWhEP / m2/year.
For 24.168 m2, 5861 MWh in 2021.
- Electricity: 34%
- Gas: 66%
Technical installation
The measurement of consumption is done, in this example, mainly via current clamps connected in the electrical panel. Communication is via a 4G modbus gateway.
How to reduce energy consumption?
Reducing its consumption by 32.5% as requested by Europe is an entirely achievable objective. We have seen above that the rationalization of consumption, through a study of actual consumption, can already lead to a reduction of 10-20%. This rationalization requires user awareness, and simple methods that consist of consuming only when necessary.
This first method is inexpensive. These are just changes of habit, and maybe a little automation (on/off of equipment)
To go further, there are other levers that can (must) be implemented, in ascending order of budget:
- The change of certain existing equipment, and of which there are more recent and less energy-consuming models (lighting, fridges, printers, etc.)
- Improved insulation, placement of double flow ventilation with heat (or cold) recovery
- Installation of renewable energy sources (solar panels, heat pumps)
