How and why HVAC systems are getting smarter

In addition to maintaining a building’s temperature, HVAC systems also control the humidity, airflow and air filtering. Consequently, the term HVAC has evolved to describe the way that people­ are provided with the most ambient and healthy environment possible.

These systems are encountered in most buildings we visit on a daily basis – from offices and manufacturing plants to schools and shopping centres.

Heating, ventilation and air conditioning (HVAC) systems are evolving at an unprecedented rate to ensure the best possible performance and energy efficiency.

But why is HVAC efficiency so important?

Heating and hot water alone can account for 60% of everyone’s total energy use according to The Carbon Trust. Good ventilation is also essential – it provides fresh air and also helps protect a building against damp and condensation – but unnecessary ventilation wastes energy and accounts for around 30% of heat loss in most commercial buildings.

Air conditioning systems, in particular, use a huge amount of energy. In fact, air conditioning can increase a building’s energy consumption and associated carbon emissions by up to 100%. 

When it comes to managing HVAC systems, the Carbon Trust maintains that a large proportion of the energy consumed by a building is likely to be wasted due to incorrect control settings, user error or poor maintenance processes. Consequently, ensuring efficient HVAC systems are installed, operated and subsequently maintained throughout their lifetime can potentially result in substantial cost and CO2 reductions.

What’s next for environmentally-friendly HVAC technologies?

Massachusetts Institute of Technology (MIT) researchers are working on what they call the “ultimate energy-efficient air conditioning system” for commercial use. The team based at MIT’s SENSEable City Lab has called the technology “Cloud Cast” and, in essence, it utilises sensors hung from aluminium rods to follow people around and adjust the air conditioning output accordingly.

Separately, MIT spinout Ecovent has recently created a new domestic ventilation system that also utilises sensors to identify when and where people are present. Ecovent’s system is centred on “smart vents” that homeowners install themselves. They plug a sensor into each room, place a control hub anywhere in the house and input the desired temperatures for each room into a smartphone app.

The sensors constantly measure a room’s temperature, and relay that information to the hub, which tells the vents how much to open or close. Co-founder and CEO Dipul Patel said that traditional HVAC systems dump air into homes indiscriminately, wasting energy by heating or cooling vacant rooms.
“Companies today are focused on more efficiency in cars, phones, and electronics,” says Patel. “But you look at a house and it’s inefficient from the ground up.” Homes with Ecovent systems installed, Patel estimates, could save roughly 10 to 15% on their utility bills annually.

Current HVAC legislation in Britain

The Energy Performance of Buildings Regulations Directive was established in 2007 to reduce carbon emissions by improving energy efficiency. It states that all air conditioning systems with an output of more than 12KW must be regularly inspected by an energy assessor and these inspections must be no more than five years apart. (Source: Department for Communities and Local Government – Improving the energy efficiency of our buildings – A guide to air conditioning inspections for buildings)

While the UK government banned the use of hydrofluorocarbons (HFCs) in new equipment in 2001, the EU Fluorinated Greenhouse Gas (F gas) Regulations of 2014 sought to minimise emissions of equipment predating the ban through leak prevention and repair.

They’ve resulted in many organisations having legal obligations with regard to the management and control of these “F-gases” – which also include perfluorinated chemicals (PFCs) and sulphur hexafluoride (SF6) – which can be contained in air conditioning units. (Source: Department for Communities and Local Government – Improving the energy efficiency of our buildings – A guide to air conditioning inspections for buildings)

Since January 1st 2015 it has also been illegal to use virgin HCFCs such as R-22 refrigerant when servicing and maintaining air conditioning equipment.

For more information on the carbon emissions of HVAC systems visit The Carbon Trust.