Performing energy audits to detect sources of waste and opportunities within an organisation’s operations is now widely regarded as an essential step in the move to improve overall efficiency, along with meeting the many rules and regulations driving such actions. For instance, many companies in the UK are now reporting their greenhouse gas emissions and energy consumption under the government’s new streamlined energy and carbon reporting (SECR) policy. Implemented in April 2019 – and replacing the Carbon Reduction Commitment (CRC) energy efficiency scheme – these new regulations require close to 12,000 companies incorporated in the UK to disclose their energy and carbon emissions.
It’s an area that’s ripe for improvement. Consultants Control Energy Costs UK’s head of business development Liam Conway, pictured below right, estimates that between 80-90% of businesses have not implemented an effective energy usage monitoring system. “Energy costs tended to be something that organisations focused on every two to three years. Now, though, with the soaring cost of electricity, gas and water, they are seeking ways to be more energy efficient by scrutinising everything from top-line spending across the business, drilling down to individual items such as motors and controls to see where savings can be made.”
Why have many organisations been slow to monitor their energy usage – and costs – previously? “Over the past five years or so, a typical metal press company, for example, might have been looking at a plus or minus 10% movement in those costs, which is not business-critical when you consider all of the aspects of a business that need to be scrutinised,” says Conway. “Now, everything has changed. Energy has become a huge consideration, an essential part of a cost-led conversation, with the need for businesses to demonstrate their sustainability credentials and the move towards net zero a part of that.”
Another motivation behind reducing energy costs lies with the supply chain. “Those who sit at the top of the chain are increasingly looking for detailed evidence of energy efficiency from their suppliers’ own operations and the impact that is having. If you can’t provide the evidence, it’s likely that someone else who can do so will win the business.” CEC UK has redesigned its in-house portal CECIL (CEC Information Library) to give businesses the data they require to identify and drive down costs, he adds.
Mari E. Haapala, digital lead for ABB’s Motion business, points to how operational data insights from electric motors have lowered the barrier to carrying out energy-efficiency audits, and how this will help industrial operators cut costs and emissions. “For many years, energy audits have been the best way to identify energy-saving potential in industrial motors, with the ultimate goal of saving energy, and therefore cutting CO2 emissions and operating costs. By evaluating a motor’s operation, an energy efficiency audit enables the operator to identify whether the motor is using more energy than required. If that is the case, they can upgrade the motor, pair it with a variable speed drive (VSD), change its operating schedule or a combination of these actions.”
TOO MANY MOTORS
A major challenge with this traditional approach, she says, is that operators typically have many more motors than they can audit. “From a practical and budgetary perspective, energy audits are costly and time consuming. A specialist consultant needs to visit the site to gather and analyse data before submitting a report with recommendations. Typically, operators can only justify audits for their largest and most critical motor-driven systems.”
However, new developments in the Internet of Things (IoT) have lowered the barrier to energy audits. “It is now possible to gather data from smaller powertrain fleets right through to large installed bases of hundreds of digitally-connected motors without calling an expert consultant to site,” adds Haapala. “Instead, low-cost sensors can be installed on motors to create digital connections from powertrains. This enables expert evaluation of motors that are remote or hard to access. Typically, the audit will result in detailed recommendations that can then be followed up by implementing the solution and mitigating risks.”
The new type of digital energy appraisal uses similar data to the conventional approach, but enhanced and with greater time-accuracy, she says. “It also builds on condition monitoring, which uses data from digitally connected motors to optimise maintenance, avoid unplanned outages, and predict when equipment and components are approaching failure. ABB can provide the audit as either a complete service, from installation of sensors, expert analysis through to recommendations and implementation, or as a partial service covering specific elements. Similarly, customers might opt to carry out some elements themselves or to deliver the complete powertrain audit internally.”
One early adopter of this digital approach to energy appraisals is SCA, a kraft pulp manufacturer in Sweden. Its mill in Munksund produces 400,000 tonnes of packaging material in an energy-intensive operation that uses more than 2,400 electric motors. Explains Anders Kyösti, SCA Munksund’s technical manager: “Electrical motors account for a large part of our electricity consumption. Given higher energy prices and the trend towards electrification, optimising energy use will become even more important in the future.” The operator is gathering data on motor performance, such as temperature, speed, vibration, operational patterns and magnetic field strength. From an asset management perspective, this data is informing SCA’s approach to operations – for example, by improving reliability and uptime.
“Using a digital energy appraisal service from ABB is providing SCA with the insight it needs to make decisions on boosting energy efficiency,” states Haapala. “Expert analysis of motor data is revealing the true power consumption. As a result, the expert can recommend what actions to take to improve efficiency, as well as the cost and emissions savings, and the budget required. In turn, SCA can precisely target its investment in upgrading only the motor-driven systems that will provide the greatest benefit.”
EXAMPLES
How might an audit look in practice? For Socotec, a UK provider of testing, inspection and compliance services, the process starts by analysing a site’s energy data, followed by a site visit to perform an energy survey, explains Jonathon Turpin, senior energy consultant. “A report is then put together where we show how much energy can be saved, as well as what the indicative financial costs will be to the client, if they implement any changes in equipment and/or controls that we have identified during the survey.”
To arrive at the financial costs, Socotec looks at the energy price (pence per kWh) of the client’s gas and electricity and shows how long it takes for each recommendation to pay for itself (annual payback) via the amounts saved in both energy (kWh) and hard cash. “We then show these as short-term, medium-term and long-term recommendations, reflecting the length of time to achieve these paybacks.” With the cost-of-living crisis and rapid inflation, this has seen previously long-term projects suddenly become much more attractive, as their return on investment is much quicker.
Turpin offers Solar PV by way of example. “Installing this a few years ago would have seen a payback in the region of 12-15 years. However, as installation costs came down, the payback fell to around eight years. In line with current energy costs, this has now come down to around three years.”