Why energy-saving plans are failing to go the distance

Depending on the relative cost of enery at the time, energy-efficiency programmes and capital investments have been a regular part of industrial life for most of the last 30-40 years. The techniques and technologies needed to improve energy efficiency are well known.

However, the universal feedback is that there are major issues surrounding the long-term sustainability of improvement programme benefits. Benefit erosion is the norm. Many suppliers and customers report a complete erosion of energy-efficiency benefits within two years of programme completion.

Why is this? Typically an industrial site’s energy consumption is driven by a wide variety of factors operational, maintenance, cultural, management etc. There is no single silver bullet that ’fixes’ energy: the operating environment is continually changing.

Efficient energy operation requires continual attention to all these details it’s a housekeeping problem. Often a site will buy in a turn-key energy-efficiency programme, have it executed, and not realise the requirements on their side to ensure that the gains are held long-term.

Determining factors

Whilst, indeed, there are single large Capex items, which can make a step change in energy performance such as. installing a co-gen unit or heat recovery scheme, in general, a site’s energy performance is driven by a large set of, sometimes, conflicting factors. These include:

• Adherence to operational targets, and understanding of deviations/corrective actions,
• The role of maintenance in energy performance equipment efficiency, reliability,
• Employed technology,
• The influence of design on performance,
• Cultural and competency issues,
• Planning and scheduling balancing yield, margin and energy.

On many sites, as a result of this complex set of drivers, energy has simply “slipped through the gaps” over recent years. Energy performance has deteriorated at the expense of short-term gains and budgetary pressures.

This was not helped by low energy prices in the late 1990s and early 2000s. Lip service was paid to benchmarking indices and in-depth understanding of the effect of the main factors on benchmarks was not achieved. Management review became “explain away the difference” rather than “drive improvement”.

In simple terms, energy saving appears attractive solid understandable technology and good payback. So why doesn’t it happen automatically? Fundamentally, it depends on whether a company or organisation really wants to, and is prepared to tackle what can be competing priorities.

If not, then this cascades through the organisation and it is common to find skewed and misaligned actions as a result. A picture emerges that shows a fragmented approach and, in many cases, no overall control of the factors that drive energy consumption.

A continual re-assessment of performance is needed to keep on top of the conflicting factors that determine a site’s energy usage. This requires tools, systems and, above all, a corporate commitment to operate in this manner.

Clearly the issue is complex. As has been explained, there is no single, instant solution. Energy efficiency requires attention to all the areas highlighted. It requires a combination of technologies, plus procedural and housekeeping approaches. These requirements are encapsulated in new global management standards on energy and CO2 management, such as ISO50001.

Detailed point solutions are, typically, simple and well known, but the overall management system is a more complex picture.

Many energy management projects have foundered in the past by trying to be too clever. It is a perfect scenario for developing overly complex models and management processes

Fundamentally, the issues are control problems; both at a management level using process data to analyse performance, detect shortcomings and drive improvement and at an operational level, some using advanced control techniques to allow the process to be run closer to energy-efficient constraints.

Accurate, reliable plant energy measurements, plus a distributed control system (DCS) process historian, provide the foundation for an integrated and consistent approach to energy management.

Modern data reporting allows focussed, user-relevant applications at all technical and managerial levels, while new measurement techniques also enhance access to energy-related plant parameters, which were traditionally excluded from the plant instrumentation set. An example of the latter is a new wireless steam trap monitor that facilitates low-cost monitoring of individual steam traps to prompt failure detection, repair and steam saving.

Such technologies, though, must be backed by a management approach that ensures the long-term sustainability of the energy-efficiency savings, and drives the improvement programme. This sets the entire site and corporate framework in which the differing levels of control operate.

ISO50001, which has been developed as the international standard for energy management by the International Organization for Standardization (ISO), is anticipated to affect up to 60% of the world’s energy consumption.

The standard specifies requirements for an organisation to establish, implement, maintain and improve an energy-management system: enabling a systematic approach to achieving continual improvement of energy performance.

ISO50001 applies to all aspects of energy use, which can be monitored and influenced by an organisation. Therefore, it provides the procedural backbone for addressing the multi-facetted issues that drive a plant’s energy efficiency.

From this standardised approach, a picture emerges of accurate and reliable process energy measurements, archived in a site-wide process historian, accessed through modern user-oriented PC interfaces.

Various control, modelling and data analysis tools utilise this data. Surrounding this is a formalised management process, which determines the accountabilities and processes to ensure continuous performance appraisal and identification of improvement actions. These can be in any of the categories mentioned above.

Many energy management projects have foundered in the past by trying to be too “clever”. It is a perfect scenario for developing overly complex models and management processes. This approach can also induce a tendency to account for all the drivers.

A better approach is to adopt a fit-for purpose, top-down vision, which defines the aims and provides the basic checks on management commitment and organisation, in parallel with a bottom-up, step-by-step approach to technical problem solving.

• Review current energy management effectiveness,
• Define management responsibilities,
• Develop simple performance review,
• Identify and implement initial low-level applications.
• Review and improve.

Experience has shown that good energy-saving initiatives will not continue to deliver sustainable long-term benefits without the framework of a sound management system. And high-quality process measurement, data management, control and focussed reporting, forms the foundation for any successful systematic, energy-management approach.

David Stockill was formerly Shell Group subject matter expert for energy management systems, where he developed the world-wide standards and energymanagement work processes for Shell Operating Companies. He now provides energy management consultancy services to Emerson Process Management.