Energy conservation vs Energy efficiency

Most modern commercial buildings are efficient, meaning they consume a relatively low number of kWh per service provided.

But very few are taking the time to reconsider how much they actually need in the first place which leads to energy wastage (e.g. overcooling of shopping malls).

In very simple terms:

  • energy efficiency is replacing an old lightbulb by a LED
  • energy conservation would then be turning the light off when you leave a room.

One of the main concerns about energy conservation strategies is measuring progress. 

Let us look at a building that consumed an X number of GWh in 2019, but consumed X-1 in 2020 thanks to the deployment of energy conservation measures, but also the temporary suspension of activities due to the pandemic. This is a point where many people lose interest in energy conservation services as  they appear too difficult to quantify.

However, there are internationally recognized standards for building a reference baseline that would reflect the consumption of the site without conservation measures.

BeeBryte’s Hive Vision dashboard provides a clear overview of generated energy savings

Traditionally, government incentives to improve a building’s energy performance highlight energy efficiency with very few mentions of energy conservation strategies.

That is why many buildings turn to buy new, more efficient equipment, without exploring ways to improve the existing.

If we take the example of space cooling, the lifespan of a chiller, responsible for production of cold, is about 15-20 years. Replacing it after 5 years because there is a newer model does not constitute a sustainable (or an economical) strategy.

There are several actions we can take before turning to equipment retrofit:

  1. Education & change of habits – keeping windows closed while the heating is on
  2. Reassessing the needs – do we truly need lights on in the office at 3am?
  3. Smart & dynamic control – a system that anticipates and adapts to changes in needs (those can depend on the climate, season, time of the day, activity etc.)

The last step usually comes in the form of a software solution which allows for a simple interfacing with the existing equipment and does not lead to any interruptions to the operation of the heating & cooling equipment. On top of that, it does not require any significant hardware investment, unlike a retrofit.

Many buildings already use some sort of automation system to control the operation of heating & cooling and other equipment, simply because it is not possible (or desirable) to manage manually. However, these systems either follow a fixed set of rules or react in response to changing conditions.

The true game changer is predictive control! A software that anticipates the weather/occupancy/activity/needs and adjusts equipment operation in advance of any changes for optimal performance and comfort.

Such an approach combines the merits of energy efficiency and energy conservation. However, the key takeaway is that, with the right strategy, even the most modern (& efficient) facilities have room for improvement and hold a potential for additional energy, cost, and CO2 savings.

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This article is published with permission from BeeBryte, provider of remote operation & maintenance services (O&M) for heating-cooling systems (HVAC-R) in commercial buildings and factories.