Cutting energy costs of buildings with drones

by Measure Australia

Everyone has experienced the disparity of temperature and humidity between, seemingly, similarly air-conditioned buildings. People who work or live in such buildings will often apply terms to them such as "cold building", or "wet" building, or even "sick" building to describe the artificially created climate within. Some buildings will maintain a steady, consistent atmosphere that can be regulated accurately while another, seemingly identical building with similar air-condition will have a physical atmosphere that fluctuates wildly according to the outside temperature and humidity. Some buildings maintain consistent annual air-conditioning costs, while others chew through excessive electricity costs for inferior results.

There are many factors involved in the creation of these disparate outcomes between similar buildings. Air conditioner maintenance, and asset management and inspection methods are obvious ones, but one of the biggest causes for a building's environmental inefficiency is thermal leaking.

Thermal leaking

In a Technology Fact Sheet regarding energy savings and air sealing, the US Department of Energy, Office of Building Technology established that air leakage "can account for 30% or more of a building's heating and cooling costs, and contribute to problems with moisture (such as mould), noise, dust, and the entry of pollutants, insects, and rodents. Reducing infiltration can significantly cut annual heating and cooling costs, improve building durability". They also contribute to greenhouse gas emissions.

This is a problem that has been known for decades but pinpointing the affected areas of a building has been notoriously difficult, even with the refinement, and increased access to, the thermal imaging equipment required. It is just too expensive, and dangerous, to send inspectors clambering over a building with thermal imaging equipment for days on end. In the case of locating cracks invisible to visual inspection but large enough to let rain in, inspectors must wait until after a rainfall has occurred. That was until the development of drones able to perform aerial thermal image capture.

The Benefits of using drones for aerial thermal image capture

Reduce heat loss

A thermal imaging survey will provide a quick and non-disruptive inspection to create a clear thermal map that are invaluable in monitoring, maintaining, and improving climate control systems throughout the building. Fixing the source of heat loss will lead to a substantial reduction in energy bills.

Locate missing and damaged insulation

Insulation has a significant impact on the energy efficiency of buildings, so it is important to locate any areas where it may be damaged or missing. Thermal imaging surveys will identify both problems with pinpoint accuracy which saves time and money when dealing with sub-contractors. They can also locate areas of insulation either disturbed by wildlife or affected by natural deterioration.

To identify air leakage

Leakage has a major impact on the energy efficiency rating of a building, Thermal surveys will locate these leaky areas with pinpoint accuracy. This will then improve building-wide ventilation and human comfort levels and reduce energy bills.

To Identify water infiltration

This is where water breaches the building from outside. Deteriorating, and damaged construction materials are most often to blame. If the building isn't watertight, the infiltrating water will cause damage to other systems and cause a cascade of other problems. This is where repairs can get REALLY costly. Because water seepage and its associated damage is often hard to see, the thermal imaging survey allows building managers to easily spot areas of potential damage well before they can cause major damage.

Locate incipient water condensation

Condensation occurs where warm moist air encounters cold surfaces – much like a bathroom's walls after a steamy shower. Wherever unseen water can condense for long periods, mould, mildew, and staining will occur. This can lead to greater damage and provides a health risk to any occupants of the building. Erratic heating and poor ventilation are the main causes of condensation. Thermal imaging is particularly useful for locating these areas quickly, and accurately which then allows a building manager to pre-emptively fix the problem. This reduces repair costs and protects the health of residents.

Assessing thermal comfort levels

Thermal comfort level is related to how content a person is with the thermal environment of the building they are in. This is different for everyone, but there is a 'goldilocks' zone where the thermal environmental levels are acceptable to most people. A range of factors have an impact, including temperature, humidity, and air turbulence level (ventilation). Thermal imaging helps to locate areas where any of these factors may be causing undue thermal discomfort, which allows building managers to adjust.

Measure Australia has the trained drone pilots, and the infrastructure to set up an aerial thermal imaging survey that will allow any building manager, or owner, to quickly assess what is needed to tighten up the building's energy efficiency. Remember that most buildings can be optimised to save 30% of their current energy costs. Contact MA to find out how you can do that.