Supply on demand

The building services industry is changing fast, driven by a determination to improve energy efficiency and reduce carbon emissions. The reasons are clear. Buildings account for at least 40% of the UK’s CO2 emissions, with the majority of these emissions generated by the energy-consuming services used in heating, cooling and ventilating.

Government success in reducing these emissions will play a large part in determining whether it meets its obligations under the Kyoto agreement. But the drive towards energy efficiency is not simply about reducing CO2 emissions. It makes good business sense too.

As the UK moves towards becoming a net importer of energy, and fuel costs rise, UK plc is realising how reducing fuel consumption can significantly help improve business profitability.

Where ventilation is concerned, energy efficiency and protecting the environment can also work hand in hand for the good of business. It can reduce air pollutants, improve health and help create a better, cleaner working environment.

If employers provide ventilation that is in line with legislative requirements, and improve air quality, employees will work more productively, studies show.

Whatever the pressures from commercial and public sector end-users, the regulatory framework is changing to ensure mechanical and electrical contractors take steps to positively embrace low-carbon technologies on behalf of their clients.

From this month, as part of the Energy Performance of Buildings Directive (EPBD), Energy Performance Certificates (EPCs) will be required for commercial buildings and Display Energy Certificates (DECs) for public buildings.

From 6 April, an EPC will be required on the sale or renting-out of larger commercial premises (total useful floor area of more than 500 m2). Then, from 1 October, an EPC will be required on the construction, sale or renting-out of all but a few exempted commercial premises.

The key articles of the EPBD are implemented in the UK through the Building Regulations Part L. As far as ventilation is concerned, Part L2 relates to non-dwellings of more than 1000 m2, with Part L2A referring to new-builds and L2B covering existing buildings.

Part L requires a maximum allowable specific fan power as part of the building services system to achieve a Building Energy Certificate.

Both sections refer to the Non-Domestic Heating, Cooling and Ventilation Compliance Guide as a means of showing reasonable provision for meeting the Building Regulations. Drill further down and you will find that Part L requires a maximum allowable specific fan power as part of the building services system to achieve a Building Energy Certificate.

It is at this point that players like Vent-Axia also have an important role to play. That is why the company has introduced a dedicated Lo-Carbon ventilation range. The VA Knowledge Bank, as it is collectively known, exists to help contractors understand issues around low-carbon ventilation, advising on how they can equip themselves to reduce energy consumption and cut emissions on a diverse range of projects.

Traditionally, ventilation systems have been driven by AC current. For the last few years, DC motor technology has advanced to allow for the use of more energy-efficient DC motors to drive the fans. These can save up to 80% in energy consumption by reducing the power drawn by the motor.

The next step combines the energy efficiency and controllability of DC motors with the flexibility to link to AC mains supply. This involves electronically commutated DC motor technology, abbreviated to EC/DC motor drives.

Alongside residential and commercial fans, Vent-Axia’s range includes heat recovery systems, air-handling units and Sentinel on-demand ventilation systems, which are used in schools, theatres, offices and public buildings (see images).

Ventilating integrated office and retail areas with residential apartments presents fresh design and installation challenges for contractors.

Vent-Axia has sought to calculate throughout its range not just the energy savings that can be made when comparing high-efficiency products with standard units but also the carbon savings that can be achieved, based on typical usage.

Vent-Axia believes its Lo-Carbon ventilation can reduce a building’s carbon emission rates by a minimum of 7 kg up to 1795 kg per annum, depending on the type and size of equipment specified, without compromising indoor air quality.

In short, to satisfy the requirements of Part L and the EPBD, EC/DC motors appear to provide the lowest specific fan power available. By using on-demand ventilation solutions, you can multiply these efficiency advantages significantly to provide low carbon solutions that meet today’s regulatory framework.