HOW TO USE THIS GUIDE

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LIMITATION: This guide has been prepared on behalf of and for the exclusive use of Sinclair Knight Merz (Europe) Ltd’s Client, and is subject to and issued in connection with the provisions of the agreement between Sinclair Knight Merz (Europe) Ltd and its Client. Sinclair Knight Merz (Europe) Ltd accepts no liability or responsibility whatsoever for or in respect of any use of or reliance upon this guide by any third party.

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1 BACKGROUND

1. BACKGROUND

This guidebook has been developed by SKM Enviros and BRE on behalf of the Ministry of Industry, Commerce, and Consumer Protection, in conjunction with UNDP, the Ministry of Energy & Public Utilities, and the Energy Efficiency Management Office of the Republic of Mauritius. Funding for the implementation of this project has been provided by GEF and AOSIS/SIDSDOCK, through UNDP.

This guidebook is provided as part of a wider programme to facilitate industry in Mauritius to implement Energy Management and conservation in Mauritius. The programme provides the following elements:

n Guide book on energy auditing in industrial applications n Guide book on energy management in industrial applications

n Software calculator tool to estimate and record identified energy saving opportunities n Theoretical training in energy management

n Theoretical training in energy auditing in industrial applications n Practical training in conducting energy audits in industrial applications

This guide book is intended as a self-help guide for use by personnel working in industrial facilities in Mauritius in the assessment of energy saving opportunities.

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2 HOW TO USE THIS GUIDE

2. HOW TO USE THIS GUIDE

This guidebook provides a basic introduction to the practical aspects of energy audits and surveys in industry. It is not an exhaustive manual but identifies the key steps required to plan the audit process, gather relevant performance data, identify opportunities and report the findings.

Energy auditing is a core component of any energy management system; unless energy use can be measured it is difficult to control and, without baseline performance metrics, a site’s performance improvement cannot be measured over time. Whilst auditing a site that has a limited number of energy meters is a difficult proposition, there are ways of gathering sufficient information to allow a practical engineer to make an educated assessment of the breakdown of energy usage across a complex manufacturing plant and identify suitable energy saving opportunities.

This guide is organised in the following way:

n Section 3 is an introduction to the objectives, information requirements and preparative steps required to begin the audit.

n Section 4 outlines the step-by-step process that makes up an energy audit and how to plan the approach depending on whether the audit is aimed at a site-wide or a single process department.

n Section 5 covers the essential data requirements and how to organise the data for effective performance analysis. n Section 6 covers energy measurement, analysis and the importance of baseline reporting.

n Section 7 includes some suggestions for identifying opportunities to reduce energy use and managing the development of opportunities from initial concept to implementation. This section also links into the Technical Appendices, which outline opportunities across common

technologies including simple checklists to guide the auditor through the processes.

n Section 8 is a summary of cost-benefit analysis, helping to develop the justification for investment in energy efficiency. n Section 9 covers the contents of an audit report

n Section 10 highlights the follow-up activities that, when carried out on a regular basis, form the core of any energy management system that is consistent with the ISO 50 001 standard for energy management.

n Section 11 introduces some of the useful hand-held monitoring tools that can be used to verify process conditions and check parameters such as power consumption and combustion efficiency.

n Section 12 is a reminder that water is also an important utility and opportunities to reduce water use can also deliver energy savings through reduced pumping and treatment needs and eliminating energy loss from hot effluents.

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2 HOW TO USE THIS GUIDE

The five Appendices cover specific issues around key universal energy technologies: n Lighting

n Compressed air

n Steam systems and fired heaters n Refrigeration and air conditioning n Electric motor driven systems.

Included in the appendices are checklists that may be referenced during the course of an energy audit that cover key energy using aspects of equipment.

To complement this guide is a software tool comprising two parts: a database for recording energy saving opportunities and a series of simple calculators for

estimating possible savings potential. Both parts require the user to enter data. The assessment tool home screen provides guidance on how to use the database and calculators. It informs where data input is required and where calculation outputs can be found.

References to the software tool are made in this document by the calculator icon (left). The icon indicates that the information presented is supported by a calculator in the tool. References to the information in this guide and use of the software tool will assist the reader in identifying and evaluating potential energy saving

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3 INTRODUCTION

3. INTRODUCTION

Carrying out an energy review is the first step for energy management. The energy audit is the starting point from which an energy review can be carried out and thus a rational energy management programme may be developed. It helps to quantify the energy usage at a site and highlights areas for potential savings and gives the data from which performance indicators can be derived.

An energy audit is essentially a study to determine the amount and cost of energy consumed and to identify opportunities for potential savings. This is achieved by carrying out a technical investigation of the control and flow of energy in the plant or a process, or even a specific piece of equipment.

3.1. Objectives

An energy audit helps to identify where and how energy savings can be achieved. Energy audits can be undertaken for the whole site, for a particular process or item of equipment. Whatever the subject of the audit, the objectives of the survey remain the same.

The objectives of the energy audit are to:

1) Quantify energy consumption for audit scope (site, area or item of equipment) 2) Identify practical energy saving projects.

3) Quantify savings in energy and monetary terms.

3.1.1. Determine current position

The first objective for a site energy audit is to quantify the amount of energy consumed on site. This will determine the current baseline position and will allow for the current situation to be assessed. When starting an Energy Management initiative it is important to determine the current position. This is necessary as it will facilitate the setting of goals and priorities for future development.

There are various elements of the current situation that need to be defined. These can be divided into two main categories: n Quantity elements: How much energy is being used?

n Quality elements: Where and how is energy being used?

3.1.1.1. Quantity elements

The quantification of current energy consumption and cost is a good starting point. In addition to indicating the magnitude of energy consumption it also helps to inform where to concentrate efforts to achieve the best results.

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3 INTRODUCTION

Monthly consumption figures over a 12 month period provide a useful method of producing a picture of energy usage. It is also important to record the type and energy intensity (calorific values) of any non-standard fuels although it can sometimes be difficult to obtain this information. Fuel costs are obviously important and any month by month variations should be noted. Cost information should include the unit cost of fuel and supply tariff (if applicable). The source of fuels and any variations in calorific value or quality should also be recorded.

The following issues need to be investigated in order to establish the current position:

Energy sources: Identify all the fuel types and energy sources used on site. These can include Electricity, Liquid Petroleum Gas (LPG), Heavy fuel oil, etc. A list of common fuels is included in the Audit Tool, including typical energy content and carbon equivalents.

Amount of energy: Quantify the amount of energy used of each fuel type. All fuel types will need to be quantified in the same units (i.e. kWh, MJ, etc.) so that their energy consumption can be compared. Consolidating all the information will give the total energy consumption of the site. However, it is useful to be in a position to determine the energy usage for each area of the plant. In cases where the plant is zoned or different areas and/or particular equipment can be measured, the energy consumption for each area should be determined. This will help to target particular areas or processes or big energy users. For example, quantifying the electricity consumption for compressed air or for a specific production line will give an idea of where energy is actually being used.

Cost of energy: The annual energy consumption cost of the site is needed so that the size of the problem is clearer. Energy cost can be compared against other baseline costs of the site. Moreover, the cost for each fuel will be different. Therefore, it is important to establish energy unit costs for each fuel. Again, it helps if all fuels have the same units so that they can be compared with each other. The Audit Tool incorporates typical calorific values of the fuels and normalises energy costs per unit of energy.

Energy breakdown: Having established the energy used from each fuel type, and their respective costs, it will be possible to create a fuel breakdown. This can be done both in energy and monetary terms. CO2 breakdown is also helpful when looking at the environmental impact of the plant. Furthermore, an energy breakdown by area or even equipment is a powerful tool which helps to identify big energy users and allow the audit to focus on areas where the greatest saving opportunities can be found.

3.1.1.2. Quality elements

Having established the cost and quantity of each energy source being consumed, the next step is to identify where and how energy is actually being consumed. This in effect is the assessment of the flow of energy through the site.

The objectives at this stage are to identify for each fuel the most important users in cost and consumption terms and to break down the usage as much as possible. Once this has been carried out, it will be possible to identify areas and specific items of plant to target for efficiency

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3 INTRODUCTION

improvement measures. Once areas that require improvement or areas where energy is wasted have been spotted, the next step is to find out how and why.

In order to assess the way energy is being used a plant walkabout will be necessary. Plant walkabouts are discussed in more detail in the following chapters. However, at this point it needs to be mentioned that during the walkabout it is important that anything that could be done differently is questioned. This will help to identify process inefficiencies and areas of energy wastages.

The objective here is to reduce energy consumption and improve energy efficiency. These are two different issues and should not be confused. There are two main questions that always need to be answered in terms of energy reduction and energy efficiency:

Energy reduction - Is energy actually needed? This relates to the areas where energy is being wasted. Old practices are not always the best practices. An investigation into such areas can help to identify significant energy saving opportunities with no or very low cost.

Energy efficiency - Can it be done more efficiently? This relates to how energy is controlled and/or is converted from one form to another. For instance the efficiency of air compressors can be improved simply by drawing in air with lower temperature, so that the conversion efficiency of power to compressed air is improved.

3.2. Required information

As discussed above the types of fuel used need to be known. Electricity, Liquid Petroleum Gas (LPG), Heavy fuel etc. should be identified and quantified. It might be more appropriate to treat compressed air and steam as separate utilities starting from the output of compressor / boiler. This will allow for a more focused analysis on particular equipment and processes. What needs to be identified is:

The quantity of each fuel: The energy consumption data can be retrieved from the utility suppliers or metering on the site.

The unit cost for each fuel: The utility suppliers will also be able to provide the unit costs. Furthermore, cost breakdown for each fuel type should also be known. For example, the day and night, or peak tariff cost rates for electricity is important for comparison with operation and energy use patterns.

Energy

Reduction

• Areas of inappropriate use or waste • Are we heating and cooling at the same time? • Are lights sleft on in an empty room?

• Are ovens left on while there is no production?

Energy

Efficiency

• Poor control or conversion efficiency

• Are we using the appropriate efficient equipment? • Are we controlling machines properly?

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3 INTRODUCTION

Where and how each fuel type is used: Where sub-metering is in place data can be available for specific areas, or equipment. For example useful information can be found in the boiler house or the compressor house log book.

Gathering information about energy consumption is an important process and it is important that all data is recorded properly. The following table is an example of how to record the required information.

Year 2012

Site / area

Energy source Units Quantity purchased in original units Quantity converted in kWh Cost Unit Cost $/kWh CO2 (tonne) Electricity kWh 2,750,000 2,750,000 $330,000 0.120 1,460 Natural Gas m3 840,000 9,240,000 $323,400 0.035 1,760 Oil litres 42,000 445,200 $25,200 0.057 110 Other fuel - - - - Total - - 12,435,200 678,600 0.055 6,616

The data from the above table can be used to create a breakdown of all the energy sources on site. A pie chart is very useful to visualise the various breakdowns. An example is shown below:

CO2 Breakdown Electricity 44% Natural Gas 53% Oil 3% Cost Breakdown Electricity 48% Natural Gas 48% Oil 4% Energy Breakdown Electricity 22% Natural Gas 74% Oil 4%

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3 INTRODUCTION

From the above figures it can be seen that whilst electricity supplies only 22% of the energy requirement, it accounts for 48% of the cost. Therefore, small energy savings in electricity can bring more significant cost savings.

After the baseline is determined it is useful to look at the most significant energy users on site. Creating a list with all the major users will help in identifying areas where greatest focus should be given for identifying savings opportunities. The list below contains examples of typical users on industrial sites.

When sub-metering is available it helps to measure the actual consumption by each user and they may be sorted accordingly. Where sub metering is not available and a user is known to be significant portable sub metering equipment may be used to take temporary measurements to inform an understanding of the actual energy use.

This type of information is needed to establish the current baseline and to identify and estimate energy saving opportunities. However, additional information will be needed to assess the practical and economic feasibility of any energy saving projects identified. The required information for assessing the feasibility of the projects can include:

The cost of energy saving projects: Having accurate cost estimates for any required improvements / modifications needed to deliver savings will help to estimate the payback period of the project. This will allow the proposer to provide a business case and helps to make an informed decision on whether to invest or not.

Operation pattern of the plant: This is needed when considering changes that will have an effect on or depend on operation patterns. For example, a process heat recovery project will depend on the time when heat is needed.

It is also important to establish the priority areas. The auditor needs to know whether to focus more on no/low cost projects or on bigger energy saving projects:

n No/low cost measures can bring fast results and boost confidence but savings may be limited whereas,

n Bigger projects on major energy users can give significant savings but may need more time and capital investment.

Electricity users Liquid Fuel users

Ovens Steam boilers

Furnaces Thermal fluid heaters

Presses Hot water boilers

Air compressors Ovens

Chillers Furnaces

Hydraulic pumps Space heating

Dust extraction system Presses

Lighting Vehicles

Air conditioning

Motors on conveyor belts Fork lift trucks

Hot water boilers Induction furnaces Space heating

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4 PLANNING THE ENERGY AUDIT

4. PLANNING THE ENERGY AUDIT

4.1. Setting the scope

The audit may cover an entire site, the services operations or a single production unit. To ensure that the appropriate information is collected during the audit the scope of the study should be clearly defined. However, the energy auditor should also be aware of and note other energy issues that might be observed during the course of an audit (for example, noting a compressed air leak on an adjacent piece of equipment or questioning significant water usage).

For a basic consumption or carbon footprint audit it will be sufficient to collect records of energy invoices for at least the past 12 months or past calendar year. This type of audit will be appropriate for high level reporting of energy consumption, cost and carbon emissions, typically used for annual reporting to shareholders or government or as a pre-audit for a more comprehensive audit of the site or process. In this case, no on-site visit is required; the audit can be completed in an office environment with access to top level energy reports and utility invoices.

The next level of audit is likely to be an assessment of the breakdown of energy use across the various processes on site. This requires a more careful approach as it will involve access to boilers, compressor houses and sub-stations to view any sub-metering and switchgear. It will also require access to utility distribution drawings and a visual inspection of large motors and heaters (or access to a motor inventory) to draw up a list of the main energy consumers. For this type of audit an escorted tour of the factory is required, so an appropriate safety briefing is required from site, including relevant Personal Protection Equipment (PPE) where necessary.

A detailed site audit with the primary objective of identifying opportunities is likely to take one or more days depending on the size of the factory. In this case the auditor may need to access the site independently, to view all major process plant and site services equipment.

For an energy management assessment the auditor will need to meet senior managers, production supervisors and plant operators to enable him to make an assessment of the organisation’s capability to implement energy management change. So, check before arrival that such people will be available either collectively on a one-to-one basis to help you form an opinion of the company’s energy management maturity.

Finally, always prepare in advance of a visit – check the company’s website for any technical background, understand the production processes and inform your host contact of your visit plan so he can ensure you have the appropriate access to people, reporting systems and technical information.

Detailed audits need to be undertaken by the appropriate persons or team. They need to be experienced and familiar with the site’s operations. The skills required cover technical, safety, accountancy and management aspects. The main skills needed are summarised below:

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4 PLANNING THE ENERGY AUDIT

n Data handling skills: Data is necessary to analyse performance and assess efficiency. In view of the large quantities of data analysis involved, familiarity with and access to computers is useful.

n Communication skills: Auditors should have good people and communication skills, sufficient strength of character to question the obvious and initiative to find solutions to problems.

n Technical understanding: An in depth knowledge of specific equipment in use at the site is desirable but not essential, as design information can be obtained at a later date; a feel for product flows and site services is more important.

n Open minded: An open mind is essential. Usually people continue doing things even when they know that there is a ‘better’ way. The fact that things have “always been done like that” doesn't mean it is the right way.

A tour around the plant should follow the process from the raw materials to final product. Each stage of the process needs to be understood. Particular attention needs to be given to:

1) Energy flows into and out of processes. 2) Raw material and product flows. 3) Wastage and effluent flows.

The pattern of operation is also important. It needs to be defined whether the process is in operation for 8 hours per day or 24 hours per day. Also the type of the process (batch or continuous) needs to be identified. For instance, in the case of a batch process the start and finish times as well as the factors that dictate them need to be identified. All the important process parameters need to be highlighted and investigated. The answers to these issues and others will only be gained from talking to the key people at the site who are:

1) Process operators. 2) Process supervisors. 3) Production managers.

It is very important that these people are involved in the audit. It is helpful to identify how they see their job and what affect this can have on energy consumption. The auditor needs to be open-minded and to ask questions and even challenge them. Operators will continue to stick to poor, old practices if unchallenged, as it is easier than changing.

A forward thinking factory will have an energy team, or even energy teams for each production area. Team members are useful; sources of information and process knowledge and will also be custodians of any opportunities, so be sure to make time to meet the energy team, either as a group or individually.

STORES O ff ic es P rodu c ti on 1 P rodu c ti on 2 Boiler house Production 3

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4 PLANNING THE ENERGY AUDIT

It is recommended that the plant is divided into appropriate zones. This will help when planning the walkabout and it also helps to focus on appropriate areas. As best practice the site layout with the associated zones should be in hand when doing the plant walkabout. An example of a zoned plant is shown on the previous page.

Then, a list with the services and technology used on site can be created on which the auditor can use to track the audit process for every zone. An example of such a matrix is shown below:

Technology topic

Zones Offices Stores

Boiler house Production 1 Production 2 Production 3 Lighting Ventilation Space heating Air conditioning Hot water Steam Hot oil Compressed air Chillers Dust extraction Building fabric Motors and drives Fans and pumps Conveyor belts Process heat Distribution

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4 PLANNING THE ENERGY AUDIT

4.2. Health and safety considerations

The health and safety of the auditor, host company employees and other contractors must always be at the forefront of planning an energy audit. The auditor may wish to use intrusive portable monitoring equipment such as gas analysers or electrical clamp on meters to gather data in which case the relevant permits to work need to be obtained; these are usually accompanied by descriptions of how the work will be carried out and the site will assess these to ensure the proposed activities are safe. Always check with your site host and health & safety manager to ensure that the equipment is fit for purpose and its use is acceptable on site. Always ensure that you have appropriate Personal Protection Equipment (PPE), either your own personal equipment or request this from site. Most companies will have a recognised safety induction for visitors and

contractors; always ask to see either an induction video, slide deck or safety procedures sheet. Always be aware of site safety issues, do not be afraid to point out an unsafe act or near miss and stop work and be prepared leave site if you are uncomfortable with the working environment.

4.3. Timescales

The time required to deliver an energy audit will depend heavily on the scope requested by the client. A short audit of annual energy use for carbon or sustainability reporting may only require a day onsite and two days to write up, while a detailed survey of a large production facility aimed at identifying opportunities could take weeks or even months. Some rules of thumb to assist in planning are audit are as follows:

n Allow 3-4 weeks for the site to assemble the requested energy and process information

n Allow 1 week before the kick-off meeting to carry out preliminary analysis of plant data (KPIs, high level regressions etc.)

n Time on site will depend on the scale of the project. Allow 4-5 man days for every £2 million (R50 million) of energy spend (your knowledge of the site and process will help to guide you to set site days).

n Allow 2 analysis and reporting days for every site day. This can be reduced if there is a relatively small number of process operations but at least as many man-days as you spend on site.

n Allow 2 weeks for the site to review and comment on the draft report before a close-out meeting. n Follow up the close-out meeting within one week with the final report.

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5 DATA COLLECTION

5. DATA COLLECTION

5.1. Assess the current situation

Audit information should be prepared in such a form as to allow comparison with historical data or available industry figures. Comparison between sites may also reveal opportunities for saving.

It has already been mentioned that determining the current position is the starting point of the energy audit. The use of the most recent 12 months’ historical data will help to calculate the annual energy consumption. This will represent the baseline. Establishing a baseline is important as future savings and energy performance will be measured against it.

It is useful to gather weekly or monthly base data on consumption and expenditure over the last year(s). The information that needs to be gathered will include not only energy consumption but also data for the factors affecting energy usage. Even though the source of this various information will be different (energy invoices, log books, accounts, etc.), it is recommended that all the information is kept in a central place where access will be easy for someone wishing to review them. A simple table with the data required is shown below:

Month Electricity (kWh) Natural Gas (kWh) Degree Days* (°C) Production (kg)

January February Etc... Total

• Degree days for heating or cooling may be an important driver for fuel consumption or chiller demand

The above table can also include for example different product groups, utility costs, energy consumption by area, and information on throughput including overall production and production by area or process.

Data collected in such a form allows performance indicators to be established in terms of specific energy ratios relating energy usage to

production, usually expressed as the energy requirement per unit of production or Specific Energy Consumption (SEC). The units used will vary dependent on the fuels used and the type of product. However, a consistent unit is recommended. The pattern of energy consumption is analysed and correlated with raw materials input, product output or hours run for production related energy usage; and factors such as average ambient temperature for space heating.

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5 DATA COLLECTION

Data collected in such a format is also easy to analyse using regression analysis to establish any relationships between energy consumption and production activity or climate factors (e.g. degree days). Such analysis can form the basis for setting energy targets for those processes where we can see a strong relationship between energy and production activity.To develop a good idea of where the energy is being consumed a good understanding of the production processes involved is essential. When an auditor or the Energy Team from another site undertakes the on-site audit, then a plant walkabout is necessary to develop a feel for the site and familiarise with the processes.

Typically, gaining an understanding of the production processes involves discussions with production management, a tour of the plant and the drawing up of a process flow sheet (block diagram). For each element of the flow sheet energy and raw material inputs, products, effluents and waste flows should be identified. Based on information available and visual checks, the relative size of energy flows and wastage should be estimated and the major energy users (both services and processes) should be listed. Sub-metering, where available, is useful in calculating the consumption of end users. A small saving on a large consumer will often be more significant as well as more achievable than a large saving on a small user. This does not mean that small users should be ignored but initial efforts should concentrate on those areas most likely to produce substantial savings.

5.2. Review historical energy consumption information

Historical data, perhaps extending back over two or three years, can be used to understand a site’s progress in developing an energy efficiency culture. Although SEC values may often be influenced by production volumes and new production processes it is useful to see how performance has changed. If detailed data are readily available they can be used to establish historical baselines and regression models. Then, the impact of any changes to the site operation can be assessed and quantified through CUSUM analysis.

Comparing performance indicators such as those mentioned above with internal and /or manufacturer standards will then enable a prioritisation of the results into categories according to the outcome:

n Good results à Action is not urgent. When the results show that the energy performance is good then it can be said that no action is urgently needed. However, the energy audit will need to be carried again in the future to ensure that good performance is maintained. n Average à Action required. Average results will mean that there are deficiencies and issues that need to be resolved.

n Poor à Urgent action is need. When the results indicate poor energy performance, urgent action will be needed.

However, it should be noted that even when the results for the site in general are good, specific areas or processes might not be in the same position. For example, the overall energy performance of a site could be good, but the compressed air system is inefficient with many compressed air leaks, poor control of the compressors, etc. Therefore, the analysis should look not only on the overall plant performance but focus on the various processes and systems within the plant.

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6 MEASURING ENERGY USE

6. MEASURING ENERGY USE

6.1. What to look for

The initial design of a system may not have been optimised. Often, an easy option or one with a low capital requirement will have been chosen, not the cheapest running cost option. The status quo should not be accepted without question. Whether the energy flows are reasonable or not needs to be established. An understanding of the processes involved and knowledge of appropriate available technologies will be needed to identify better options.

When undertaking an energy survey on specific equipment (i.e. air compressors, boilers, steam systems, etc.) the relevant appendices at the end of this guide can be used. These provide useful information on where focus should be drawn.

However, there are things that can be easily identified during the audit and the auditor should constantly be looking out for areas of energy waste. A list of things that can be easily picked up during a walkabout is given below:

Look Listen Feel

Conveyor belts running unnecessarily Machine noise when no production Compressed air leaks

Lights left on when not needed Dust extraction system on when not needed Room temperature too low / high Oven doors left open wasting heat Compressed air and hot water leaks Air draughts through open doors Doors left open when heating is on Motors left running when not needed Hot un-insulated pipe work

6.2. Areas to focus

When looking at energy usage, the ‘energy onion’ provides a useful analogy to an energy system. The process or end user is at the centre of the onion, which determines the production-driven energy requirements of the site. Once this has been confirmed, the next layer of the onion is the energy distribution system - network of wires, pipes and ducts delivering power, steam compressed air and other utilities to the process.

Once the distribution system has been reviewed, the methods of controlling the supply of energy through the networks to the process can be addressed. This could include pressure or flow controls in steam systems, voltage control in power systems or temperature control of chilled water supplies.

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6 MEASURING ENERGY USE

Having assessed the control of the energy supplies, the next layer of the onion represents the energy conversion plants. This is where primary energy supplied to site in the form of fuel and power is converted into useful utilities – steam, compressed air, cooling etc. – that are used by the production process. Finally, once you are happy that the energy conversion processes are appropriate it is time to address the outermost layer of the onion and review the energy supply contracts.

n End User: how energy is used within a specific process / piece of equipment

n Distribution system: how energy is distributed (compressed air, steam, water, hot oil distribution systems) n Controls: how energy is controlled (energy management systems)

n Generation (conversion): how energy is converted (air compressors, boilers, boilers, chillers) n Energy Supply: How primary energy is supplied to the process.

6.2.1. Energy end use

Starting at the centre of the onion, it is important to understand how much energy the production process should require from a theoretical and practical standpoint. This should define the base energy demands for the process and act as a guide for the sizing of distribution networks. Where the end usage is inappropriate such as the use of compressed air for cleaning it may be possible to remove the load altogether. Where this is not possible, it may be possible to reduce energy consumption by reducing leakage or improving insulation.

Reduced end usage demand will also reduce distribution losses as less energy will need to be distributed to meet the reduced demand. It may also be possible to rationalise the distribution system in the light of reduced end use. Investigations into reduced leakage, improved insulation, reduced supply pressure etc. may also increase distribution efficiency.

Before looking at the conversion efficiency, good reduction opportunities should already have been identified. In reality it is often more difficult as end usage is the most difficult aspect to change.

In looking at a process or large consumer the aim is to answer a number of questions. An example of a pump is discussed below:

Question Rationale

Why is energy required, and what is the process/plant item doing? Familiarisation with the process. Is the use necessary, and do we need to pump the fluid? Load reduction opportunities.

Can the heat demand of the process be reduced? Investigate heat recovery opportunities Do we need to pump all the fluid all the time? Can we better control

the pump to meet our needs and reduce energy consumption?

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6 MEASURING ENERGY USE

Question Rationale

Is the pump motor larger than it needs to be? Is the pump correctly sized for the task?

Oversized equipment run inefficiently and waste energy.

Alternative ways to meet the need? Old practices are not always the best ways to do a job.

Do we need to pump the fluid at all? Could we use a gravity tank, is there some other method of accomplishing the task?

The situation may have changed considerably since the original design and the pump may not be required at all or a much downsized version may be sufficient.

In any situation the focus should be first drawn on the most significant energy users. With the energy breakdown undertaken combined with the list of users mentioned in the third chapter, the major users for each energy source should be easy to classify. This will help in identifying significant saving opportunities and maximizing energy as well as cost savings.

6.2.2. Energy distribution

Some rationalisation of distribution systems may be possible. There are several issues that need to be investigated when assessing distribution systems. First of all an assessment needs to be made to determine whether it is economic to decentralise certain loads. Identify any redundant pipe work and make sure it can be removed. Long pipe runs should also be an area to focus and make sure that pipe work is appropriately sized.

For the purposes of this module a steam distribution system is used as an example. Below are a number of the issues to be addressed.

Comparison of useful / parasitic loads: The actual product energy demand needs to be determined. Then the proportion of the total demand that is made up of parasitic loads such as pipeline pressure drops or pumping demands should be estimated.

Pipe work: The correct sizing of pipe work is important. Retrofitting over time can exceed the capacity of base systems and increase pressure drop losses. Conversely, an older site where production plants have been decommissioned leaving an over-sized steam main may suffer from higher than expected standing losses. Insulation is also important, as proper lagging can help to reduce distribution losses significantly. There are several international standards for insulation; one useful reference guide is BS5422 (2009).

Pumps and fans: For centrifugal pumps and fans the electrical power requirement varies as a cube law proportional to pump speed. The application of variable speed control can produce substantial savings in suitable applications.

Steam Pressure: The higher the steam pressure the greater the losses in heat and leakage terms from the system. Flash losses in condensate and pressure losses in pipe work will also be greater.

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6 MEASURING ENERGY USE

Condensate Return: All recoverable condensate should be returned to the boiler feed water tank. Check to see how whether condensate is recoverable and if it is metered. If condensate return is metered, make sure that the rate is as expected.

Similar issues should be investigated for other distribution systems, such as compressed air circuit, hot water, hot oil, etc.

6.2.3. Energy controls

Once the process energy demand has been established and distribution systems assessed, attention can turn to the control of systems to deliver the required energy. No / low cost savings can frequently be realised by just improving the way the process is controlled. Controlling is very significant for compressed air, steam and hot oil systems.

For example, sequence controls for two or more compressors needs to be optimised to ensure that the compressed air system delivers only when there is demand for compressed air. More sophisticated control systems are now available that makes multi compressor installations more efficient.

When a system has an off-load control, there is a pre-set pressure range such that the compressor off loads at the higher value and loads at the lower. However, the main drawback is that an unloaded compressor will still consume between 20-40% of its full load power for on/off control and 70% for Modulation Control.

For cases where several compressors of varying sizes are installed the selection of the most suitable compressor available for the prevailing duty is critical in terms of energy efficiency. The relative efficiencies of the machines should also be taken into account before setting up the control system.

6.2.4. Energy conversion

To achieve savings in this area demands knowledge of the relevant technologies and what is current best practice. Design data on the plant concerned should be obtainable from documents on site or from the equipment

manufacturers. Measured performance can then be compared to best practice, design or previous performance data.

System Things to check

Boiler

Fuel / air ratio

Exhaust gas temperature Feed water temperature

Boiler blow down rate and total dissolved solids (TDS) levels

Air Compressors

Air intake temperature Moisture content of air intake

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6 MEASURING ENERGY USE

However, there are simple actions that can be taken to improve the conversion efficiency of a system. The list below summarises the items that need to be checked in an energy audit survey regarding conversion efficiency of boilers and air compressors:

Further information regarding these can be found in the appendices at the end of this guide.

6.2.5. Energy supplies

Energy supply and conversion often go hand-in-hand, as the availability of primary fuel will often determine the selection of boiler or power generation technologies. If there is a sufficient base load requirement for heat as steam or hot water and an acceptable supply of clean fossil fuel is available, a combined heat and power plant may make economic sense; in an appropriate location with access to a sustainable, managed forestry industry, there may be biomass available as an alternative fuel. Combined Heat and Power (CHP) or on-site generation may also be appropriate if there are grid capacity or reliability issues, and the energy audit should consider alternative fuel sources if appropriate.

6.3. Benchmarking and baseline definition

A performance baseline is essential if changes are going to be made to process or service operations, so understanding the starting point is a critical stage in energy auditing. Often this will be a simple performance indicator expressed as kWh of energy consumption per unit of output (SEC). This is a useful measure when comparing performance with sister plants or competitors (if that information is published). Knowing where the plant stands in relation to an industry benchmark is helpful in deciding where investment or operational change is required.

The disadvantage of using SEC as a benchmark is that the production volume inevitably dominates the calculation and it is all too easy to explain poor performance by saying that production was lower than usual. A better tool is to find a relationship between energy and production activity, so that variance needs to be explained in terms of poor or good operation or equipment malfunction. Managers can use such a variance analysis to catch and rectify poor performance at an early stage.

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7 IDENTIFYING OPPORTUNITIES

7. IDENTIFYING OPPORTUNITIES

Once the data collection phase of the audit is completed, the identification and costing of potential improvement measures and projects begins. This gives an opportunity to collate any ideas and to generate a prioritised list of potential measures.

It is important at all stages to discuss ideas with the appropriate people to see whether similar measures have either been tried before and failed or considered before and rejected because of process or other limitations.

Results should be communicated with the relevant stakeholders in order to evaluate the various measures. The objectives at this stage are to: 1) check what measures will work

2) check what measures are appropriate

3) study interaction with the measure and other projects 4) establish the cost of the measure

5) calculate benefits arising from the measure 6) compare rival measures and prioritise 7) reach conclusions

8) create action plan

For each of the measures identified there are issues that need to be taken into consideration. There should be a check to ensure the measures are acceptable for:

n Environmental and Health and Safety reasons: Make sure the measure does not have a knock on effect and it does not breach existing or proposed regulations.

n Best solutions: Gains should be examined over the long term, not just the short term.

n Acceptable Solution: Take into account any other reasons that may prohibit the implementation of the measure. n Approximate Costing: Budget figures for suppliers to give approximate area for costs

It is also important to inform staff about measures that are being discussed and what the end goals are. This is vital, especially where measures include projects involving the installation of new equipment or controls. These measures will not deliver the expected savings without people being trained to use the new equipment.

Last but not least feedback should be requested from the staff / operators. Ideally, the appropriate staff should be included in the survey. They are familiar with the various processes on site and they should be able to highlight energy wastages, process inefficiencies and to identify opportunities.

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7 IDENTIFYING OPPORTUNITIES

As best practice all identified opportunities should be recorded in a database. This will allow for future review of the status of each opportunity making sure that nothing is missed. A database of opportunities helps to inform an estimate of the expected savings. An example of the database as found in the software tool that accompanies this guide is shown below:

The database should be reviewed frequently and be kept up to date.

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8 COST BENEFIT ANALYSIS

8. COST BENEFIT ANALYSIS

Opportunities generally fall into three categories:

n No-cost behaviour change, such as switching off lights, reducing thermostat set points or fixing leaks. These should need no financial justification and be implemented as a high priority. The decision to implement such projects should be within the remit of the plant manager, maintenance manager or energy manager. A certain level of awareness and procedures may need to be put in place to facilitate these. n Low Cost projects that need little additional investigation and are likely to have a rapid return on investment but do require some

expenditure. Ideally these should be funded from the revenue budget as they are likely to recoup the expenditure within the same financial year. The decision to implement such projects should rest with site management and should be integrated with maintenance schedules if possible.

n Capital investment projects that either require significant funding despite a short payback, or have a payback period in excess of one year. These usually require a financial justification and an investment requisition to be submitted for board approval.

When considering capital investment projects, some far-sighted companies will ring-fence a proportion of capital for energy, environment or health and safety compliance projects. However, most companies will rank all investment opportunities in the same league table and implement those with the best rate of return.

Energy projects will usually fall into a low risk category of investment – they rarely involve adopting leading edge or untried technologies and the longer term value of savings is likely to rise in step with increased energy prices.

In order to present an effective case to management to gain any form of commitment and investment, a transparent financial and technical appraisal must be put forward. Management will look more favourably on proposals that represent the best investment, that optimise benefits, that sufficiently address risk management issues and which include satisfactory performance analysis.

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8 COST BENEFIT ANALYSIS

In putting a case together the steps below should be followed:

n Identify potential savings. n Identify measures.

n Establish the costs and savings. n Calculate the key financial indicators:

o Simple payback;

o Gross/net returns and their rates;

o Discounting and net present value (NPV); o Index of profitability (IOP).

n Optimise the return.

n Establish the size of the overall budget. n Optimise capital expenditure.

n Prioritise the projects.

The main issues that result in a failed case are poor base data, poor justification and the lack of a ‘do-nothing’ scenario. Ensure the figures add up and can withstand scrutiny.

Other factors that may make the case more favourable are including information on maintenance savings and estimating increased productivity.

Whilst information describing simple payback, is easily presented it can lead to misleading results. In some organisations this may not be in their best interest as they will not lead to the best investment choice. This is because simple payback does not take into account savings over the lifetime of the project or the time value of money. Therefore, better simple metrics are net return (which is a measure of the benefit) and average net rate of return, which annualise this benefit over the lifetime of the project.

Some organisations use discounting and net present value (NPV) for project evaluation. However, even sophisticated metrics have their limitations. For example the disadvantage of NPV is that it does not take into account the initial capital (CapEx) outlay.

The most transparent metric is probably the index of profitability (IOP) which does take into account the CapEx outlay and should be at least 1 for a project to be considered.

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9 REPORTING

9. REPORTING

The report from an energy audit and opportunities survey may need to address a number of different audiences; the way in which the report is presented will depend on the individual circumstances; a single report may be produced that contains all the information collected during the audit and presented in different ways, or it may be preferable to produce different reports that are tailored to suit each intended audience.

Senior management will want to see headline figures for current total energy consumption and cost, specific energy consumption per unit of output and, where relevant the site’s carbon footprint. The management team will also need to see summaries of the key cost saving

opportunities, ideally in a simple table showing a brief description, estimated energy and cost savings, implementation costs and simple payback calculations, prioritised by return on investment.

Energy managers will want to see a more detailed analysis of energy performance, including where possible a breakdown of energy consumption by department, energy targets and recommendations for additional metering and energy reporting processes. This will enable them to provide timely performance reporting for site management and flag any incidences of poor performance. They will also need a summary of opportunities, but with more detail of how to implement projects or what additional investigations are required to reach a go/no go decision for investment purposes.

Production managers will want to see energy allocations for their specific area of responsibility and any operational improvements that may be possible with limited investment or behaviour change. They need to see that they can track the impact of changes and may well be the driving force behind additional metering requirements.

The engineering manager will want to see details of any opportunities that may involve equipment modification or new process plant. He will be concerned with the availability of resources to design, plan, procure and install any new technology. He will also be concerned that he has the resources available for any maintenance programmes such as regular air leak or steam trap surveys.

9.1. Template

With these wide-ranging expectations, typical report templates may include the following sections:

1) Management Summary.

2) Action Plan / Recommendations.

3) Review of site energy consumption and cost, including a breakdown of energy use by department where possible. 4) Discussion of existing energy reporting procedures.

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9 REPORTING

5) Process energy performance, broken down by department. Use this section to discuss regression analysis, target setting and performance reporting.

6) Site services energy performance – boilers, compressed air, process refrigeration, other cooling systems, water and effluent, building services (HVAC, lighting, domestic hot water).

7) Summary of opportunities. Different summary tables according to the sites requirements may be presented; these may include summary tables of opportunities by fuel type, or by no cost/low/capital cost type.

Summaries of each opportunity should also be presented, an example format is presented in the figure, right.

8) Metering and measurement of energy use. Indicate any gaps in measurement and recommendations for additional metering.

9) Appendices. Include any detailed calculations,

assumptions, spreadsheet models and equipment data sheets here.

The software tool includes a number of tables and graphs that may be suitable for use in reporting of items 3 and 7 above. Opp ID Opportunity Title Energy (kWh) Cost (MUR) CO2 (tonnes) Capital Cost (MUR) Payback (month) Priority OPP-00020 Recover heat from air compressors 250000 7500 67 10500 16.8 High

Process / Technology Description

Recover heat from the exhaust air from the air compressors

Rationale

Recovering heat from the compressors will save fuel oil during the winter months

Opportunity Description

Duct the exhaust air from the compressor coolers into the factory next to the locker room.

Risks

Overheating the lobby area during a mild winter

Next Steps

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10 POST-AUDIT ACTIVITIES

10. POST-AUDIT ACTIVITIES

10.1. Action plan

The prime objective of an energy audit is to leave the site with an action plan that will, if implemented, result in cost savings, increased profitability and sustainability for the business. Therefore it is important to follow up any recommendations with offers to support the site in implementing projects. This support could be as simple as identifying equipment suppliers, or could require detailed design, procurement and project management support. Many companies are not focused on energy management and do not have the in-house skills to progress many opportunities; they need advice and support to realise the potential energy savings.

10.2. Continuous improvement cycle

Energy auditing should form part of a wider energy management programme such as that described by ISO 50001, “Energy Management System”, and the accompanying Code of Good Practice for Industry. It is not a one-off process; energy audits or plant energy walkabouts should be repeated frequently to ensure the efficient operation of the plant. The position will need to be determined again and re-assessed against the baseline and benchmarks to review progress.

Creating opportunities for regular energy walkabouts by those responsible for energy use, and involvement of operators within this process is a key part of increasing awareness and engagement with the workforce.

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11 MONITORING & MEASURING EQUIPMENT

11. MONITORING & MEASUREMENT EQUIPMENT

There are various useful tools that can be used during the energy audit. A list of useful tools is shown below:

Permanent or portable electrical meters: When the appropriate sub-metering is not installed, portable meters can be used to measure energy consumption on specific equipment or lines. This will not provide the annual energy consumption of the equipment but it will give valuable information about their energy consumption.

Light meters: Lighting levels can be measured with light meters. When the lighting levels in a room is known, it can be determined whether or not there is excessive lighting. This will help to identify energy saving opportunities by removing excess light fittings.

Temperature probe: The temperature on distribution pipe work, water tanks, etc., can be measured with temperature probes. This will give an indication of the amount of heat losses that can be used to justify insulation improvements.

Thermal imaging: Thermographic imaging is a diagnostic survey technique using an infrared camera for locating areas of temperature differential. Thermal images can help to identify heat losses and reduce energy wastage.

Combustion analysers: Portable combustion analysers are a useful means of checking boiler efficiency or burner performance. Using

electrochemical sensors the hand-held device takes a sample of flue gases and tests excess oxygen, carbon monoxide and dioxide. Coupled with the stack temperature these measurements are converted into the fuel conversion efficiency.

Ultrasonic leak detectors: These are especially useful for detecting compressed air leaks in a noisy factory environment and can also be used to detect faulty steam traps. Equipped with a pair of headphones and a directional acoustic sensor, the leak detector can be used to scan the factory and any leaks will be detected as a specific frequency above the general background noise. The user then homes in on the source of the leak, confirms and tags its location and notes the strength of the leak to help prioritise the repair programme.

In a large factory a leak detector such as this can pay for itself in a matter of weeks with regular and frequent surveys.

Monitoring and targeting equipment such as moisture content measurement, run-hour counters on air compressors and ammeters on motors can also help in capturing energy data and identifying energy saving opportunities. Be alert for control panels on inverter motors where kWh readings are often displayed but rarely recorded.

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12 WATER AND WASTEWATER

12. WATER AND WASTEWATER

Although water is not addressed specifically in this guide, the user is encouraged to consider water as an important factor in energy management. Water is both an energy consumer (through pumping and treatment costs) and a carrier (as a heating or cooling medium), and can also be a source of energy (for example in a heat pump). Therefore the same principles apply to managing and minimising water use:

n measure usage as a function of production;

n define a baseline reflecting current plant performance;

n set targets based on known process performance characteristics; n monitor consumption against targets and compare against the baseline; n make a change (process, operational or management);

n measure the impact of that change;

n review targets, reset baselines and continue the management cycle. Examples of poor water management might include:

n fixed flow circulation of cooling water through coolers that are not operational; n once-through flow of water on liquid ring vacuum pumps;

n discharge of hot cooling water direct to drain;

n use of high quality process water for cleaning or cooling.

Industrial wastewater is also a potential source of energy, either because it is discharged hot directly to drain or it is cooled before discharge. It can be a potential source of process heat such as pre-heating dyehouse make-up water, or at higher temperatures can be used as a heat source for heat pumps.

As with all forms of energy, avoid unnecessary use, fix leaks as soon as practicable and consider recycling water several times depending on the quality requirements of the process.

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Appendix A – INDUSTRIAL LIGHTING

Appendix A INDUSTRIAL LIGHTING

Lighting is essential for making the work environment safe and for allowing staff to perform their tasks comfortably. It can be a significant energy user accounting for up to 40% of an organisation’s electricity bill. Even making small adjustments to lighting can significantly improve the working

environment, help reduce electricity consumption and, at the same time, minimise CO2 emissions and save money.

A.1 Identifying energy saving opportunities

Energy savings in lighting systems can be realised in a number of areas. When starting out looking for opportunities the following suggests a simple approach that could be used:

n Assess the lighting levels. Are the lighting levels suited to the application and can excess lighting be avoided?

n Assess the lighting technology type. Is it the most appropriate and efficient for the given application? Is the rendering and colour suited to the application?

n Assess light distribution. Is the majority of the light delivered to the intended work area and is it correctly dispersed over the work area? Are the most efficient luminaries used and properly cleaned and maintained?

n Assess the lighting controls. Ensure the lighting is controlled in such a manner as to only deliver the right amount of light to the right areas at the right times only.

Definitions:

Lamp: the source of the light (i.e. the bulb) Luminaire: a light fitting that incorporates the lamp Watt (W): Measure of electrical power used by the lamp. Lumen (lumen): Measure of light energy emitted from a source.

Efficacy (lumens/W): the amount of light provided relative to the amount of energy used, once the lamp has reached full brightness. The higher the value the more light is gained for the same

energy.

Colour rendering (Ra): the ability of a lamp to show surface colours accurately. The lower a lamps Ra value relative to an ‘excellent’ value of 100, the poorer the lamp’s colour rendering ability. Colour temperature (K): Measure of the colour appearance of a light source ranging from ‘warm’ light (i.e. the light a candle produces) through to ‘cool’ light (i.e. a bright white fluorescent light).

Lamps below 3,300 K are classed as ‘warm’ whilst those above 5,300 K are ‘cold’.

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Appendix A – INDUSTRIAL LIGHTING

The following sections provide background information to assist in the assessment of lighting systems.

A.2 Recommended standard maintained illuminance

Providing lighting to higher levels than is necessary wastes energy and is expensive. Ideal lighting levels in industrial applications are presented in the table:

Illuminance (lux) Task / Activity / Interior

2 Healthcare ward night lighting

20 Unstaffed gangways

50 Remote operated processing, person-sized under-floor tunnels, cellars, underpasses, healthcare corridors (night), cable tunnels, indoor storage tanks 100 Circulation areas, entrance halls, corridors, rest rooms, store and stock rooms, healthcare wards (general), changing rooms, auditoria

150 Stairs, escalators, travelators, loading ramps/bays, staffed gangways

200 Toilets, foyers, lounges, plant rooms, switch gear rooms, turbine halls, archives, library bookshelves, monitoring automatic processes, dining rooms 300 General machine work, manufacture and assembly (rough), retail sales area, packing and handling areas, welding, office (lowest), reception desk, _{filing, exhibition general lighting, sports halls, teaching areas} 500 First aid rooms, laboratories, kitchens, writing, typing, reading, data processing, CAD workstations, conference/meeting rooms, offices (highest),

switchboard, post room, medium machine work and assembly, general inspection areas, control rooms, retail till area, hairdressing

750 Grinding and engraving, fine machine work and assembly, critical inspection and repairs, paint spraying and polishing, technical drawing, ceramic decoration, meat inspection, chain stores

1000 Healthcare examination and treatment, colour inspection, precision decorative grinding and hand painting, precision assembly, quality control, typesetting, gauge and tool rooms, retouching paintwork, cabinet making

1500 Electronic workshops, testing, precision assembly, fine work and inspection

2000 Steel and copper engraving, assembly of minute mechanisms, finished fabric inspection 100/500 Entrance halls/enquiry desks

100 (at floor level) Corridors, passages and stairs

300-500 General offices and computer work stations 300/500/750 Rough/medium/fine bench and machine work

300/500/1000/1500 Rough/medium/fine/precision electrical equipment manufacture 100/300/300 Bulk storage/small item racking/packing and dispatch

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Appendix A – INDUSTRIAL LIGHTING

A.3 Lighting power consumption

For lighting power consumption, general benchmarks have been set by surveying existing installations. The power consumption depends on the lighting level required, as shown below.

General Factory Lighting Benchmark Consumption (W/m²)

300 Lux 500 Lux

General lighting for open areas 5 – 6 8 - 10

For warehouse areas the power consumption benchmark is dependent on the aisle width and height.

Warehouse Lighting Aisle width (m) Mounting height (m) Benchmark Consumption (W/m²) 300 Lux 500 Lux 1.2 4.5 8 14 2.4 6.5 8 16 3.0 8.0 9 17

A.4 Colour rendering and appearance

Colour rendering should be considered when selecting lighting. Each type of lamp provides a different colour of light. In general the more detailed work being performed the closer to white light will be required. Colour rendering is measured according to the Colour Rendering Index. Each lamp type is placed in a colour rendering group depending on its colour rendering index.

The colour appearance of a light source can range from ‘warm’ light (i.e. the light a candle produces) through to ‘cool’ light (i.e. a bright white

fluorescent light).Choosing a lamp with the wrong appearance can have disastrous results in businesses where identification or matching is important, for example, food processing, textiles and retail.

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Appendix A – INDUSTRIAL LIGHTING

Colour Rendering Colour rendering performance Colour rendering ID group Colour rendering index (Ra) Typical application

Excellent 1A =>90 Wherever accurate colour matching is

required, e.g. colour inspection

Good 1B 80-89 Wherever accurate colour judgements are

necessary , e.g. shops and offices

Moderate 2 60-79 Wherever moderate colour rendering is

sufficient

Poor 3 40-59 Wherever colour rendering is of little

significance

None 4 20-39 Wherever colour rendering is of no

importance

Colour appearance Colour appearance class

Correlate colour

temperature Typical application

Warm Below 3,300 K Domestic-type situations

Intermediate 3,300 – 5,300 K Combined daylight and electric light

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Appendix A – INDUSTRIAL LIGHTING

A.5 Characteristics of different lamp types

The table below shows the characteristics of different lamp types commonly used in offices or production areas and workshops. For lighting in external areas, such as car parks and storage areas, low pressure or high pressure sodium lighting with photosensors is considered best practice.

Lamp Type General Colour Rendering Index (Ra) Task illuminance (Lux) Average installed power density (W/m²)

Offices Fluorescent – triphosphor 80-90 300 7 Fluorescent – triphosphor 80-90 500 11 Fluorescent – triphosphor 80-90 750 17 Compact fluorescent 80-90 300 8 Compact fluorescent 80-90 500 14 Compact fluorescent 80-90 750 21 Metal halide 60-90 300 11 Metal halide 60-90 500 18 Metal halide 60-90 750 27

Production areas, workshops

Fluorescent – triphosphor 80-90 300 4 Fluorescent– triphosphor 80-90 500 10 Fluorescent – triphosphor 80-90 750 14 Fluorescent – triphosphor 80-90 1000 19 Metal halide 60-90 300 7 Metal halide 60-90 500 12 Metal halide 60-90 750 17 Metal halide 60-90 1000 23

High pressure sodium 40-80 300 6

HOW TO USE THIS GUIDE

Contents

1.

BACKGROUND

2

2.