The Ecodesign Directives and a significant proportion of the Building Regulations obligate everyone involved in the ventilation equipment supply chain to strive for maximum efficiency. David Millward, Group Product Manager (UK & Ireland) at Elta Group, explores how the latest electronically communicated (EC) motor technology could prove to be a silver bullet to this challenge.
The specification and installation of new ventilation equipment requires consideration of a number of factors. Everything from installation costs and energy efficiency, through to legislative compliance and control for the end-user, affect which system is most suited to a particular application.
For many years, alternating current (AC) motors have been the most popular in fans, but emerging technology has led to a shift away from this. Lower energy EC motors are becoming an increasingly common option, thanks to their superior efficiency, alongside a number of additional benefits to ventilation systems.
Sustainability is a massive issue in construction in general, and this is certainly true for the ventilation industry. Environmental concerns are playing a huge role in the development of products, which increases the focus on energy efficiency and CO2 emissions.
A factor that is often overlooked is the additional energy loss – surplus to specific fan power (SFP) – associated with speed controls. These can be significant, and should be included in calculations of the total power consumed by a ventilation system.
EC motors help to offset this issue, as they negate the need for a mains-powered speed controller by incorporating it into the fan. This significantly reduces total energy consumption compared to an AC motor, contributing to a greener product and, crucially, reducing the running costs associated with the fan.
Significantly, especially in the wake of the latest Ecodesign Directives, the improved performance of EC motor-controlled fans leads to a reduction in CO2 emissions. By operating at a lower current, this new wave of technology drastically boosts efficiency, without sacrificing on performance.
Stay in control
From an end-user perspective, ensuring a comfortable internal atmosphere will always be a top priority. The ability to easily control fan speed is crucial to this, because it allows the output of the fan to be matched to the specific requirements of that location. This also has a knock-on effect on energy expenditure, as it prevents unnecessarily excessive fan speed from racking up running costs.
Controlling fan speed with an AC motor is feasible, however this often requires an external controller that can have a negative effect on the overall lifetime of the fan and, in some cases, increases its noise during operation. EC motors have speed control built within them as standard, as well as automatic overload protection.
Reducing the energy costs of a fan is one thing, but making sure that it is simple and straightforward to install is another. A built-in speed control on EC motors makes commissioning easier (and cheaper), and because it is connected directly to mains power, an electrician isn’t required to wire the controller.
EC controls also stay the same size, whereas an AC fan requires a specific speed controller to fit the fan power. For example, a 3 AMP fan needs a > 3 AMP controller, a 10 AMP fan needs a > 10 AMP controller, and so on. This means that controls get bigger and heavier as the fan power increases, making installation more challenging in tight spaces.
The technological development of EC motor-powered fans is underpinned by legislative change. Contractors must meet increasingly stringent efficiency requirements which, in turn, shifts the focus of manufacturers onto supplying ventilation products that meet this demand.
EC motor technology can allow ventilation products to meet the latest efficiency requirements. Some of the latest products have been designed to ensure compliance with legislation due in 2021, with the aim of future-proofing fans against further changes to regulations.
Those working in the ventilation industry are often left frustrated at the rate of change of legislation, which means products are at constant risk of withdrawal. Opting for a ventilation strategy that future-proofs against this, while providing optimum performance and minimising running costs, should be the priority for ventilation specialists.