Find your strategic partner to cut energy use

With increasing demand for electrical energy, prices will inevitably rise – a situation that is exacerbated by the crisis of falling generating capacity. By the middle of this year, coal-fired stations that have been supplying the equivalent of six million homes will be mothballed to comply with EU regulations on CO2 production. Prices will likely increase to cover the extra costs involved in importing gas and electricity to make up the shortfall. Faced with this, large energy-using industries are looking for ways to cut their energy bills. Many look for quick wins like switching off lights when not needed, or moving to a different supplier. But for the largest users – industries such as metal processing, chemical, oil and gas, cement manufacturers and paper mills – how much of an answer do these represent? Switching to a different supplier may provide a temporary solution, but prices will still rise and the energy user is still at the mercy of the market. Turning off lights has a literally visible effect, but for a large paper mill, heavily dependent on motors for pumps and fans, this can only have a relatively small impact on overall energy use. Some 65% of energy used in industry is used by motors, yet only 34% of respondents in a recent survey had performed a company-wide energy audit to see where they were using energy and how it could be reduced. This makes it unsurprising that most businesses are unaware of the significant electrical energy-saving opportunities of using a variable-speed drive (VSD) and high efficiency motor on motor-driven applications, such as pumps, fans and compressors. VSDs adjust the output of an application, such as a pump or a fan, by controlling the speed of the motor, ensuring it runs no faster than it needs. This often cuts energy consumption by 20-50%. In contrast to 'quick wins', it is this technology that promises to have a significant long-term effect on the energy bills of major industrial plants. To help VSDs make the maximum impact on the bottom line over an extended period of time, energy-intensive industries need to take a plant-wide approach and look at the long term. They need a strategic partner that bases its offering on a philosophy of energy saving; one that integrates both products and services to drive down energy use. A plant-wide approach For large users, those looking to realise savings from 5,000 MWh and above per year, with a return on investment in under three years, it makes sense to adopt a plant-wide approach to adopting VSDs. This is enabled by ABB's DriveSave scheme, which allows large energy users to adopt a more strategic, partner-based approach to investing in energy-saving capital equipment. DriveSave works by measuring the energy consumption of all suitable pump, fan and compressor applications. Based on this measurement, the potential savings are assessed and agreed with the end user. It is then ABB's responsibility to install the quantity of VSDs necessary to achieve these guaranteed savings. Should the identified savings be less than 90% of target, ABB will compensate the customer, whereas if the savings are more than 110% of the target then ABB secures a bonus. ABB's scheme aims to identify all the localised opportunities for VSD installations spread across various departments of the plant. This has major advantages compared to the piecemeal approach of assessing each application individually for its energy-saving potential and then ordering VSDs to suit. DriveSave amalgamates them into one blanket energy-saving proposal, cutting the time and effort involved in purchasing energy-saving projects and making each project more cost effective. In addition to the guaranteed energy savings and the design, installation and commissioning of the VSDs, the scheme also offers a five-year warranty for all of the installed drives, together with a five-year preventive maintenance programme. Steel company forges energy partnership One company taking this approach is Tata Steel, which used the DriveSave philosophy to make substantial savings across several of its plants throughout the group. The company worked with ABB to identify possible applications across its Port Talbot works in South Wales. The DriveSave initiative will save over £650,000 and 4,000 tonnes of CO2 a year by installing VSDs on more than 60 fixed-speed motors across the site, ranging in power from 15 kW to 200 kW. Amalgamating the works into one large project saved time and effort, and ABB was also able to offer low harmonic solutions as the company had concerns about power quality. The process has been so successful that Tata Steel is now implementing this approach at other sites. In South Yorkshire, the company worked with Halcyon Drives, an ABB Drives Alliance member, and ABB system integrator Drives and Automation to identify inefficient processes that were ripe for improvement. One of the projects, carried out at the Aldwarke Bloom Caster complex in Rotherham, South Yorkshire, is set to save the company £250,000 a year. Drives and Automation replaced existing fixed-speed, direct-on-line motors in the plant with low voltage motors, controlled by four ABB low harmonic variable-speed drives – two at 400 kW and two at 570 kW. Other projects include saving £10,000 a year on a scarfer application at the company's plant in Stocksbridge, which uses a propane burner to remove impurities from the steel ingots. The impurities, in the form of waste gases, are then removed by an exhaust fan, run by a 132 kW motor. Originally, the fan was run constantly at full speed, with its output constricted by a damper. Halcyon Drives proposed a 132 kW ABB industrial drive. As well as saving energy costs of around £9,700 per annum, the new drive application also saves 82.5 tonnes of CO2 and cuts energy use by 165,000 kWh. Following installation, the ABB drive achieved payback in under one year. Tata is also saving a further £68,000 a year on the energy costs of pumping applications at its Rotherham mill. The long view The other aspect of the strategic approach to energy saving is to take a long-term view of energy management, which involves partnering with a vendor at every stage of the VSD's lifecycle to ensure it is delivering maximum energy efficiency. With DriveSave, the first step is an energy appraisal process, which looks at existing installations and assesses their potential for energy efficiency improvements by installing modern VSDs. This can also highlight areas where the drive could help modify the operation of the process to make it run more efficiently or effectively, saving time, resources or waste. As a partner in energy saving rather than a mere vendor of kit, ABB provides lifecycle services to ensure that a VSD or motor is looked after throughout its working life. In many instances, it can help with the installation and start-up or commissioning of the drive and motor. Support available throughout the product's life includes maintenance assessments, preventive maintenance and reconditioning, to spare parts and repairs on-site or in ABB workshops. Advice can be given on upgrading entire systems to the latest technology, or to extend the functionality of existing drives and motors. Other issues might include the possibility of retrofitting existing drives with modern technology, adding the latest software or hardware to improve the performance of the application, or recycling of all removed drives and motors to the latest legislation. Taking the strategic view of energy management ensures you are not relying on the scattergun approach of quick wins, but are taking planned steps to ensure the long-term sustainability of energy use and the health of your bottom line.