The LEAN principle is transparent, worker-centric and when applied to energy monitoring, energy management and distributed systems, yields quick and positive results, says Patrick Marti, who takes the readers through the processes step-by-step.
DATA ACQUISITION AND REPORTING
Implementing green policies to reduce carbon footprint, saving energy and resources in a sustainable way needs controls. The usual practice often contains only two extremes: set a large project into motion or do nothing. LEAN is an intermediate approach which requires a number of smaller actions to reach substantial results. It might not appear as spectacular as a large project at first glance, but it is very effective in practice.
Today’s energy efficiency programmes involve consultants and specialists, expensive equipment, large systems and corresponding large amounts of money and time. Therefore, the decision-making process becomes difficult, with protracted approval processes. Also, they do not often yield return on investment at the rate one hopes to achieve.
RELEVANT QUERIES OR WISHFUL THINKING?
How would it feel if energy monitoring and optimisation was quick and simple to set up, with available personnel and moderate expenses? How would it be to access data and monitor systems without consultants or suppliers? How would it be to let the people having direct influence on the use of energy and resources adjust their systems directly with adequate, simple and transparent data? And what a good feeling to be able to extend, adapt and modify the monitoring as you like it, at any time, at no extra cost? The LEAN approach probably has answers to these questions.
In distributed systems, smaller widespread installations like energy transfer stations, for instance, are not spectacular areas to optimise and monitor. However, as they are numerous, even relatively small improvements can have a considerable impact. The same can be applied to pumps, chillers, valves, lights, among other things.
Studies show that 10% to 15% of energy savings can be obtained only by displaying the energy consumption to the people using it. Another 10% to 15% can be achieved by actively controlling the usage of energy in an installation.
The optimisation of multiple smaller objects make the LEAN approach to energy efficiency in distributed systems, together with the possibilities of standard technologies available today, an interesting source of saving.
WHAT IS LEAN?
LEAN means the ability of people in an organisation to observe and improve the main value added process by systematically eliminating all the waste. Along with this, concepts like one-piece flow, visualisation of status, involvement of workers, test platforms and flexibility are also part of LEAN.
The search for optimisation takes into account the entire added value chain, from the supplier to production and to customers. And last, but not least, it needs a constant monitoring of unbiased performance indicators to ascertain the progresses and unveils new potential areas of optimisations.
The opposite concepts of LEAN are large, complex, centralistic, expensive improvement projects, where the data is not visible and the workers are kept out of the decision-making loop.
Regarding the controlled usage of energy and resources, the LEAN approach could be simplified into a three-step programme, which could be repeated to augment improvement:
- Observe and understand the energy consumption.
- Identify the most simply influenceable parameters and define the actions.
- Implement immediately the actions, measure the results, and then start again with Step 1 for the next improvement cycle.
WHERE TO START FIRST?
Electricity, potable water, gas, oil, transport, space, stocks, working hours and many more are resources used in district cooling processes. Most of the savings proposed today concern the design of new plants and the introduction of new core technologies in the main production process. However, as the installed base has grown, not too many investments are dedicated to the optimisation of existing infrastructures. However, in future, optimising operations and retrofitting parts of existing installations will gain relevance.
As electricity has to be produced, and might become increasingly expensive, focusing on electricity consumption systematically is a good starting point to establish a continuous improvement process which can then be applied to other resources and also influence the design of new solutions.
Step 1: Observe and understand the energy consumption pattern.
Small-scale trial and analysis of results is one of the keys to making quick progress in energy monitoring. It starts with the selection of the part of an installation and setting up an adequate sensor network, followed by connecting these sensors to an effective monitoring and data collection instrument.
The thumb rule is: develop the sensor network step-by-step and expect not to cover everything. The idea is not to search for the ultimate coverage and accuracy, but to make a start. Getting 90% of the consumption with one to two per cent accuracy is enough to detect and monitor profitable optimisation potentials. A higher coverage and a better precision might sound attractive, but might lead to expensive additional investments in time, material and money, ruining probably the ROI of a project.
Things to remember:
- Select an installation or a part of an installation which either uses a lot of electrical energy (chillers for instance) or is operated in large numbers (pumps, lighting).
- Involve your operation staff and the plant electrician to define the measuring scenario.
- Add communicating electrical sub-meter devices to your electrical panels. The installation can be done within hours by the plant electricians.
- Connect the meters to a data visualisation and data logging equipment like Saia S Energy Manager, simply with a two-wire data connection.
Immediately, the consumption data starts flowing and after only a few hours, it will already be possible to observe the behaviour of the installation. First diagnostics can be established by in-house technicians about differences in consumption between similar equipment, or equipment running without contributing to the production of anything. This will lead to more precise investigations.
Step 2: Identify the most effective parametres and define the actions.
Having observed and discussed the results with your staff, first define which simple action is going to reduce the consumption. Select one action and set the energy reduction target.
Step 3: Implement the actions immediately and measure the results; then start with Step 1 again.
As the actions are straightforward, implementing the corrective action is also possible within a very short time. Replacing defective components, replacing a component with one with higher efficiency, requesting maintenance on malfunctioning equipment or switching off unnecessary equipment are typical actions at this stage. Once the action is taken, follow up the data and verify if your targets are achieved.
Based on the initial results, it is already time for the second round of optimisation. Now, go to Step 1 again.
In further rounds, it is perhaps time to duplicate the sensing equipment on other equivalent processes or to go further into details. If you think about the hundreds of energy transfer substations, for instance, each with technical room, lighting, pumps, ventilation, air conditioning, just by monitoring the electrical energy used and seeing them within expectations, will motivate you enough to save energy.
THE IMPORTANCE OF ACCESS TO DATA
In the LEAN approach, data as well as the visualisation of status and visualisation of demand are necessary to all those directly involved in the production process.
Those involved will continuously take the data into account, make the validation and compare them to the output of their process. They will, then, be less reluctant to be accountable for results for the improvement they have suggested. Also, they take ownership on their process, proposals and results more easily. This is the benefit that centralised, consultant-based projects seldom achieve over years. However, it needs to be remembered that access to data must be open. Any non-traditional tools or licenses, which would implicitly generate a limitation of the access, need to be avoided. For this reason, the data logging and visualisation device to which electricity metres are connected for the initial evaluation, should guarantee the following:
- Easy two-wire connection for the meter network and easy set-up of meter names and addresses – the electrician must be able to do the connection and parameterisation.
- Direct visualisation of consumption of individual meters, groups of meters or total, ideally in a locally installed display.
- All data used in the visualisation must be exportable as an Excel file locally, over an Ethernet Network or over GSM.
- Data, as well as alarms and graphs must be accessible via the Internet.
- The station must accommodate more energy sensors if needed in further steps.
- The station must allow a seamless integration into an energy control and management system controls.
Meeting with the above criteria means that data access and transparency is given to any worker who is able to influence the consumption, anywhere and at anytime.
By using standard technologies from the web and the IT world, the data collected is immediately available as Excel sheets or web pages or as attachments to an e-mail or as data for a SQL database to anyone in an organisation. Users have a simple access, corresponding to tools – office, Internet Explorer, PDA or PC – that they even otherwise use. The process, therefore, comes with no additional cost. An added benefit is that data archiving can be done by simply storing the Excel files automatically. This also implies that additionally, the system can easily be extended to any timeframe and that the initial investment can be reused totally in another energy management automation project.
THE BENEFITS OF THE LEAN APPROACH
Following are a few of the benefits in a nutshell:
- LEAN allows fast response time.
- The progressive, step-by-step development of energy optimisation generates immediate results.
- As the barriers for installation, evaluation and actions are not difficult to overcome, savings start quickly
- In case of a large project, should a step prove to be inadequate, it can be quickly corrected at nearly no additional cost.
- If a step proves to be rewarding in a large project, it can immediately be replicated/multiplied without waiting for the end of the project.
- The learning curve is fast and reactive.
LEAN limits exposure to bad investments, as time and money are safely used:
Smaller investments can be done by quick implementation and by proceeding step-by-step. Large investments will only be released if the return is proven on a small scale. The project benefits from immediate progress, and provides a gradual growth of experience from the inside.
LEAN increases the commitment from the bottom to achieve sustainable results:
As energy saving becomes part of the normal operations of a project, systems fall into place and begin to generate natural and continuous improvement.
By adopting a worker-centric analysis and action schemes and by giving employees access to the consumption data, LEAN helps develop in the staff an understanding of the processes they need to manage. This, in turn, helps increase a sense of commitment and involvement in the project, its implementation and success among the employees.
LEAN can be applied to both small and large installations: With the LEAN approach, it is possible to start optimisation programmes throughout all operations. Thus, distributed systems can be addressed with the approach with equal success as central systems and installations of any size.
A lot of organisations want to implement energy-saving and energy-use optimisation without taking proper cognisance of their situation. They have inadequate or no data, and no frame of reference for comparison. Also, they may not have a system in place to delegate responsibility to suppliers and energy producers.
What needs to be remembered is that if the responsibility for optimising energy usage rests with you, then the evaluation of the consumption data is yours too. It should not be delegated without getting into the risk of misunderstanding the data, have incomplete information or miss the targets you had in mind. To avoid such pitfalls, and to reap benefits of consistent and usable data over the lifetime of an installation, four conditions need to be fulfilled:
- The data must be live, accurate and represent 80% to 90% of what is consumed.
- Data collection must be flexible and evolve as the installation progresses.
- Data must be in a standard format and easily handled by web protocols or standard IT protocols.
- Data ownership must be with the customer and not with a consultant or supplier.
Optimisation of energy consumption is a never-ending process. For this reason, using the LEAN approach includes data collection, analysing, action, implementation and controlling them by dividing them into short cycles. This yields quick results. Since employees are directly involved in the production process and influence measures, investments and results, increasing their understanding of processes will prove beneficial in the long run. Further energy management can be implemented on the basis of this first step. LEAN, therefore, helps companies to move forward from bottom to top, influencing the operations of existing installations as well as new designs.
The writer is the Deputy General Manager and Director, Corporate Sales, Saia-Burgess Controls, Switzerland. He can be contacted at: firstname.lastname@example.org