Electrical energy management systems

Since the introduction of Appendix 17 in the first edition of the 18th Edition, the electrical industry has seen a steady move and shift in focus towards energy efficiency. With the publication of the 2nd Amendment to the Wiring Regulations, the concept of the prosumer installation has also been introduced, along with a recommendation to measure and monitorenergy through the use of an electricalenergy management system.

Current sensor directional arrow W e can see a shift to energy efficiency and management through other standards and legislation such as ISO50001, IEC60364, BS:EN16247, SECR and ESOS. Although ESOS and SECR legislation is aimed at larger organisations, we can still look at the concepts and requirements and apply these to all sizes of businesses looking to save energy.

The traditional concept of an energy user as either purely a consumer or producer is also changing and we are now seeing the idea of a user being both, or being a prosumer. This change in how energy is used and produced has occurred as energy efficiency and renewables have become an increasing part of modern installations. This change needs us to look at new ways to monitor and manage energy usage and energy production and enable the user to use this information to manage an installations’ energy.

Energy management systems

To enable this management of energy we need an energy management system (EMS). The purpose of an EMS is to help users to save and monitor their energy by utilising sub-metering, current sensors and monitoring software. The EMS should be capable of measuring and recording energy consumption and automatically sending the metered energy data to a software system through a variety of communication methods, such as RS485, for analysis and reporting on the energy usage.

Sub-meters

Sub-meters are typically seen in a 96x96 form factor and will have a minimum capability to measure active and reactive energy. Additional measurements such as voltage, current, power (W, VA, VAR) and power factor are also common. Modern metering can also enhance the information available to the user by incorporating power quality measurements and monitor for voltage dips, swells, interruptions and harmonics in accordance with BS:EN50160.

Current sensors

In order to make the calculation for energy, current measurement is required together with voltage. Current transformers have a primary and secondary current ratio, with the primary current being related to and sized based on the maximum current demand of the conductor, the secondary output of the sensor will be either 5A or 1A.

When installing current transformers, it is important to remember they are directional and will have some form of indication on how they need to be orientated during installation. Typically, we will see a moulded arrow on the sensor which should point towards the load – failure to do this will produce incorrect measurement calculations in the metering.

Prosumer installation

Energy management software

The final part of the system is the software. The goal of this software is to enable the reporting and management of energy and, increasingly, the power quality of the installation. Remote collection of the measurement data through communication protocols such as RS485 or Ethernet can be automated by the software. The measurements from the sub-metering can then be used to generate automatic reports, with the software sending relevant data to specific people or departments based on what they need to know.

By monitoring energy it can be quantified in the same way as other raw materials to help reduce the cost of products or services, with energy consumption data being reported to financial personnel to compare and validate billing data from energy suppliers. Maintenance engineers can have reports on power quality measurements to help identify the possible causes of malfunctions (interruptions, harmonic distortion, etc.) and help to manage preventative maintenance activities through the observation of energy inefficiencies.

Other aspects of the energy and power usage control can also be automated. By monitoring when and where energy is being used, the EMS can remotely control processes to improve energy efficiency. Power can be turned on or off by sending notifications and managing the automation of processes based on a calendar or on electrical values or events detected by the sub-metering.

Environmental measurements such as air quality, temperature and light can also feed into the system to provide valuable information on the installation and provide further information to automate energy consumption.

Sub-meter

The future of energy measurement

As installations continue to move to the new prosumer model, the need for energy to be monitored to ensure a return on investment on power generation systems (renewables) and to manage the energy produced in the most efficient way will become more prevalent. This need for energy management will open up opportunities to install sub-metering and energy management systems to an established customer base driven by regulations, legislation, standards and a desire to reduce energy consumption.

FIVE PREDICTIONS FOR THE ENERGY AND UTILITIES INDUSTRY IN 2022

David Hall, VP Power Systems at Schneider Electric UK and Ireland talks us through the company’s predictions for the top five trends that will fuel the next stage of the energy management revolution in 2022.

EV service technician installing a terminal The global shift towards more climate-conscious energy efficiency has accelerated the need for sustainable technology to deliver a cleaner, greener, and fairer energy system. The UK’s 2050 Net Zero pledge deadline looms. Together, the IPCC’s latest report on climate change, COP26 and the UK government’s 10-point-plan for a green industrial revolution have added greater focus. Businesses and consumers alike have a growing appetite for sustainable initiatives.

Technologies for renewable electricity generation, energy storage and power grids are essential to decarbonise existing supply and meet growing electricity demands from the rapid electrification of buildings, transport, and industry. Clean technology, modern power systems and green energy sources present a vast investment opportunity for businesses.

Considering this, here are Schneider Electric’s predictions for the top five trends that will fuel the next stage of the energy management revolution in 2022.

Electric vehicles: push the pedal on a low carbon future

The UK government has already set a clear direction for the industry by banning the sale of new petrol and diesel cars by 2030 and trucks by 2040 to reduce carbon emissions and stimulate the ‘green economic recovery’. As the adoption of EVs accelerates, however, the added pressure they place on ageing electricity networks will continue to increase.

Energy companies and the government must incentivise the transition to electric vehicles towards a low carbon future. A big part of this is ensuring that the infrastructure and power supply match the demand for EVs. Work is underway to put in place a more resilient foundation to connect and power more significant numbers of EV charging points. DNOs need to work quickly and get this right to enable a successful transition from petrol and diesel to EVs and ensure a positive impact across the broader energy network.

Microgrids fit for the future

Another important area to get the ball rolling on sooner rather than later is to ensure the grid is ready for a digital future. More and more of our energy supply will come from disparate renewable resources, such as microgrids and intermittent renewable energy sources – creating a need for a more decentralised energy supply network.

According to Schneider Electric’s recent research, 25.4% of UK and Ireland businesses claim to have installed a microgrid or renewable power source (e.g., solar or wind) to reduce their environmental impact. While offering a reliable alternative to the traditional central power grid, the grid itself needs to cope with more complex and bi-directional flows involved with these new technologies and monitor supply and demand more effectively. Investing in the digital grid will be critical to opening up these possibilities for a more clean and efficient energy supply network in 2022.

SF6-free – the silver bullet to sustainability

SF6 (sulphur hexafluoride), while rare in the atmosphere, is one of the most potent greenhouse gases in the world. One tonne of SF6 has the same global warming potential as 23,500 tons of carbon dioxide. Most SF6 used in the electrical industry is for electrical insulation and current interruption within power networks.

Replacing SF6 with pure air solutions is essential to reducing environmental risk across power networks. SF6 currently has a special exemption for use in electrical distribution across many geographies. However, as alternatives become more readily available, the EU and a range of countries and territories are considering measures to restrict its use, which we expect to hear more about this year.

The need for sustainable technology to deliver a cleaner, greener, and fairer energy system has accelerated

Embrace the growing opportunity in onshore wind

The growth in clean energy projects such as wind power is essential to a more sustainable world. It’s becoming more apparent that wind energy is more efficient, produces no greenhouse gas emissions and is becoming increasingly popular as a renewable energy source. By 2040, the world of electricity will be profoundly different: the share of electricity in everything we do will double, reaching at least 40% of final energy consumption, and six times more electricity will be generated from solar and wind. Even with its benefits, connecting wind to the power grid brings with it a unique set of challenges, including surges, dips, distortions, and stringent grid code requirements.

Next year, wind developers should also look towards combining wind generation with energy storage to be more flexible. The time is ripe for increased investment in onshore wind.

Net zero commitments at the heart

With the focus on sustainability and COP26 taking the world by a storm last year, it is clear businesses need to ensure this is a priority in their plans. In fact, according to Schneider Electric research, more than nine out of 10 (91.5%) UK and Ireland respondents said reducing their carbon footprint is a priority for their organisation, with a quarter of businesses (27.4%) saying it is their top priority this year.

As we move into 2022, we will be focusing more on ensuring these climate ambitions turn to action. Businesses must act now to handle energy management better to reduce energy waste and create a greener future. Acting sustainably, reducing our carbon footprint, and building smarter cities is the only way we will reach net zero targets.