With energy efficiency high on everyone’s agenda, it is important that electrical engineers and contractors offer customers the latest information about reducing fuel consumption, and to provide energy efficient solutions wherever possible. Here, Newey & Eyre’s Kevin Norman shows how helping customers to better manage their energy needs doesn’t have to be complicated
Although addressing problems with energy efficiency can be viewed as an unenviable task, by using a simple four step approach, contractors can take a ‘back to basics’ look at the efficiency of a system and easily recommend positive changes.
Understanding consumption
The first step in this process is to understand where existing energy is being consumed. An overview of energy usage will enable an electrical engineer to review recent electricity bills and observe the behaviour and attitude of people using the building or facility as part of a basic energy audit.
After this, more in-depth measurement and analysis can be achieved through the installation of energy metering i.e. simple kWh meters, metering distribution boards and PowerLogic metering and data collection – all of which can be fitted in new installations or retro-fitted. The contractor is then able to identify areas that are wasting energy and where changes can be made. The installation of sub-metering also allows customers to comply with the Building Regulations Part L stipulation that 90% of fuel used in a building must be accounted for by end use category.
Fixing the basics
Once energy usage and wastage has been established, engineers can then move on to step two – fixing the basics. Simple changes can often make a big difference to the customer, so it is better to look at these first prior to designing a complex and expensive energy saving solution.
These can include challenging the attitudes of building users and encouraging simple energy drives such as switching off equipment at night. It is also advisable to consider the power consumption of different technologies and installations and see if more efficient like for like replacements are suitable – from low loss transformers, low voltage lighting and dimming controls, to improved insulation.
Another consideration, where applicable, is power factor correction. The volume of electric motors, induction heaters and fluorescent lighting installed in commercial and industrial buildings has increased significantly in recent years, and this greater load all acts to reduce the power factor and thus the efficiency of the electrical supply. The power factor should be 0.95 lagging or better, and electricity companies are now charging for poor power factor – known as the ‘reactive power charge’.
By using power factor correction, the reactive current drawn from the electrical supply is reduced, creating greater supply capacity through more efficient energy use. For the customer, they can not only save money by avoiding the reactive power charge and climate change levy payments (if they reduce their kWh consumption), but it is estimated that they can save 95kg of CO2 per kVAr of power factor correction installed each year.
A wise move
One of the key ways to reduce electricity consumption is to use equipment more intelligently, which brings us to step three – automation. By using simple control and command products, we are able to better match supply to demand.
From building management systems, time switches and presence detectors, to lighting controls and time delay relays, there are many products available for use on new and existing installations. Control and command products are also suitable for integration inside standard distribution boards and DIN-rail enclosures.
Where appropriate, HVAC controls such as variable speed drives (VSDs) could also be considered. Able to optimise HVAC pump and fans, a VSD removes the need for valve and damper flow controls, and can give energy savings of up to 50%, with just a 20% reduction in speed.
Always evolve
Because buildings and their usage develop and change over time, what saves energy today, may not always be the right solution in five years time. Therefore, it is important to monitor and improve – step four.
Energy efficiency is a topic that continues to remain at the top of the agenda. From the extremes of weather we see here and around the world, to the price increases driven by rapidly decreasing reserves, these markers all serve to remind us that we must act now to be more economical with the resources we have. As professionals working in the electrical industry, it is our responsibility to ensure that we provide conscientious solutions and educate customers wherever possible to reduce their energy consumption.
With this in mind, Newey & Eyre has put together an eight page energy efficiency solutions product guide to put green solutions at the electrical professional’s fingertips. The guide also includes an ‘Energy Efficiency Knowledge Centre’ to give customers and staff a quick reference resource for information on relevant legislation and government funding initiatives.
