Since 2010, the UK Government has been increasingly proactive in convincing businesses to operate more energy efficiently. This culminated in the creation of the Energy Act 2013, which includes a financial incentive for lasting reductions in electricity demand.

For businesses to achieve this, facilities managers must first invest in smart meters to accurately monitor and ultimately reduce electricity usage.

Modern smart meters can tell engineers how much reactive power (kVArh) is generated from a plant’s energy supply by identifying the difference between working power and total power consumed. Reactive power is the extra power consumed in a circuit that is not useful. It is created as a result of normal impedance in a system and, in effect, it is a total of the amount of wasted power in a system that the user still needs to pay for.

To tackle high levels of reactive power and improve overall efficiency, businesses should invest in equipment to safely filter out reactive currents from systems. For example, the REOWAVE passive CNW 898 filter is an industrial unit that can reduce reactive power to improve overall power quality and drive down energy bills. It can also increase the service life and reliability of electrical systems in the process.

Reactive currents are not the only problem. As counterproductive as it may seem, smart meters can actually generate their own power quality problems in unprotected electrical systems. They transfer data over power lines using ripple control technology, which has been linked to electromagnetic interference (EMI). In effect, the device being used to boost energy efficiency is itself contributing to problems that increase wastage. 

Growing problem

EMI caused by smart meters is indicative of a growing problem in the industrial sector. The rise of the internet of things has led to plants becoming increasingly reliant on electronic devices transmitting data. While many of these use wireless signals to communicate rather than transmitting through power lines, the presence of multiple devices is a common cause of interference. It is likely that several of these devices will have differing power requirements or use a switch mode power supply (SMPS), both of which negatively effect power quality.

Most electrical engineers are aware that their systems should comply with electromagnetic compatibility (EMC) directives, such as 2004/108/EC in the EU. EMI is a big problem in power systems that, like harmonic currents, can lead to inconsistent power and damaged components. It is a particularly big issue for the renewables sector. Most renewable energy is generated in DC form, which must then be converted to AC before it can be used in the electrical grid. This is done using inverters that work efficiently but lower the power quality. This affects many critical components, including the SMPS and transformer windings.

EMC filters can be used to limit the interference. These low-pass filters are designed to stop the flow of EM noise and reflect it back at the original source. The filters must be able to handle the power dissipation, so it is advisable that electrical engineers work closely with power quality specialists to ensure they choose the right solution.

For devices such as smart meters, plant managers and electrical engineers should use power line communication (PLC) filters to remove this interference from the network. It is important that plant engineers accurately specify the frequency range when selecting a filter in order to effectively eliminate interference. Typically, a filter that complies with EC Directive 89/336/EEC will provide sufficient filtration, such as the 50kHz to 20MHz range of REO’s CNW 161 filter.

Investing in smart meters is just the first step that engineers and managers should take in driving down energy costs and improving efficiency. If businesses want to benefit from the financial incentives offered by the UK Government, they must ensure that their systems can effectively act on the insight provided by smart meters.